Stanley P. Azen PhD
Professor, joint appointment with the Keck School of Medicine of USC, Department of Preventive Medicine
Room: SSB 202G
Phone: (323) 442-1810
Stanley Azen is currently Professor and Co-Director of Biostatistics in the Department of Preventive Medicine at the Keck School of Medicine of USC. Dr. Azen is also Assistant Dean of Research Integrity. At USC, Dr. Azen was one of the "founding fathers" of the Graduate Programs in Biostatistics, Epidemiology, Molecular Epidemiology and Public Health. He is also the Co-Director of the Keck School of Medicine of USC MS program in Clinical and Biomedical Investigations, a "track-based" program to train clinical fellows and junior faculty in research methodology leading to publications and/or a grant proposal. In 1998, he was one of two recipients of the USC Associates Award for Excellence in Teaching, in recognition of his programmatic development and mentoring of students. In 2006, Dr. Azen received an honoary Doctorate in Biomedical Innovations from the University of Salerno, Italy. Dr. Azen is also the Director of the Statistical Consultation and Research Center at USC. The Center is actively involved in the design, conduct and analysis of clinical trials in cancer, cardiovascular disease, diabetes, gerontology and ophthalmology. Research studies range from the evaluation of vitamin B supplements on coronary artery disease to determining the prevalence and risk factors of ocular disease in Latinos and in a multi-ethnic cohort of children.
Dr. Azen has published over 300 scientific papers and two textbooks, including a scientific publication appearing in the Journal of the American Medical Association reporting the benefit of a Lifestyle Redesign® program in independent-living older adults. This study was reported on national radio and television, and had a Nielsen rating of 12.1 million people. Dr. Azen is also the founding editor and Editor-in-Chief of Computational Statistics and Data Analysis, the official journal of the International Association of Statistical Computing, published by Elsevier in Holland. Finally, Dr. Azen continues his career as a professional pianist, performing at two well-known Pasadena restaurants. He has released three albums entitled: "Regressive Moments," "Timed Series" and "Clustering En Stanza."
Doctor of Philosophy (PhD) in Biostatistics
University of California, Los Angeles
Master of Arts (MA) in Mathematics
University of California, Los Angeles
Bachelor of Arts (BA) in Mathematics
University of California, Los Angeles
McIlvaine, E., Borzabadi-Farahani, A., Lane, C. J., Azen, S. P., & Yen, S. L. (2014). Apriori feasibility testing of randomized clinical trial design in patients with cleft deformities and Class III malocclusion. International Journal of Pediatric Otorhinolaryngology, 78, 725-790. doi:10.1016/j.ijporl.2014.01.006. Link to full text
OBJECTIVES: To assess the feasibility of randomizing treatment (surgical vs. non-surgical) for correction of a Class III malocclusion (underbite) resulting from an earlier repair of cleft lip and palate.
MATERIALS AND METHODS: Surveys about willingness to accept randomized treatment during adolescence were mailed to the parents of cleft lip and palate patients under the care of Children's Hospital Los Angeles between 2005 and 2010. The inclusion criteria were patients with cleft lip and palate, Class III malocclusion due to maxillary deficiency, and absence of medical and cognitive contraindications to treatment.
RESULTS: Out of 287 surveys, 82 (28%) were completed and returned; 47% of the subjects held a strong treatment preference (95% CI, 35-58%), while 30% were willing to accept randomization (95% CI, 20-41%). Seventy-eight percent would drop out of a randomized trial if dissatisfied with the assigned treatment (95% CI, 67-86%). The three most commonly cited reasons for being unwilling to accept random treatment assignment were 1) the desire for doctors to choose the best treatment, 2) the desire for parents to have input on treatment, and 3) the desire to correct the underbite as early as possible.
CONCLUSION: Based on this study, parents and patients would be unwilling to accept a randomly assigned treatment and would not remain in an assigned group if treatment did not meet expectations. This highlight the limitations associated with randomization trials involving surgical modalities and provide justification for other research models (e.g., cohort studies) to compare two treatment options when randomization is not feasible.
Clark, F., Pyatak, E. A., Carlson, M., Blanche, E. I., Vigen, C., Hay, J., Mallinson, T., Blanchard, J., Unger, J. B., Garber, S. L., Diaz, J., Florindez, L. I., Atkins, M., Rubayi, S., & Azen, S. P. (2014). Implementing trials of complex interventions in community settings: The USC-Rancho Los Amigos Pressure Ulcer Prevention Study (PUPS). Clinical Trials, 11, 218-229. doi:10.1177/1740774514521904. Link to full text
BACKGROUND: Randomized trials of complex, non-pharmacologic interventions implemented in home and community settings, such as the University of Southern California (USC)-Rancho Los Amigos National Rehabilitation Center (RLANRC) Pressure Ulcer Prevention Study (PUPS), present unique challenges with respect to (1) participant recruitment and retention, (2) intervention delivery and fidelity, (3) randomization and assessment, and (4) potential inadvertent treatment effects.
PURPOSE: We describe the methods employed to address the challenges confronted in implementing PUPS. In this randomized controlled trial, we are assessing the efficacy of a complex, preventive intervention in reducing the incidence of, and costs associated with, the development of medically serious pressure ulcers in people with spinal cord injury.
METHODS: Individuals with spinal cord injury recruited from RLANRC were assigned to either a 12-month preventive intervention group or a standard care control group. The primary outcome is the incidence of serious pressure ulcers with secondary endpoints including ulcer-related surgeries, medical treatment costs, and quality of life. These outcomes are assessed at 12 and 24 months after randomization. Additionally, we are studying the mediating mechanisms that account for intervention outcomes.
RESULTS: PUPS has been successfully implemented, including recruitment of the target sample size of 170 participants, assurance of the integrity of intervention protocol delivery with an average 90% treatment adherence rate, and enactment of the assessment plan. However, implementation has been replete with challenges. To meet recruitment goals, we instituted a five-pronged approach customized for an underserved, ethnically diverse population. In intervention delivery, we increased staff time to overcome economic and cultural barriers to retention and adherence. To ensure treatment fidelity and replicability, we monitored intervention protocol delivery in accordance with a rigorous plan. Finally, we have overcome unanticipated assessment and design concerns related to (1) determining pressure ulcer incidence/severity, (2) randomization imbalance, and (3) inadvertent potential control group contamination.
LIMITATIONS: We have addressed the most daunting challenges encountered in the recruitment, assessment, and intervention phases of PUPS. Some challenges and solutions may not apply to trials conducted in other settings.
CONCLUSIONS: Overcoming challenges has required a multifaceted approach incorporating individualization, flexibility, and persistence, as well as the ability to implement needed mid-course corrections.
Nadeau, S. E., Wu, S. S., Dobkin, B. H., Azen, S. P., Rose, D. K., Tilson, J. K., Cen, S. Y., & Duncan, P. W. (2013). Effects of task-specific and impairment-based training compared with usual care on functional walking ability after inpatient stroke rehabilitation: LEAPS Trial. Neurorehabilitation & Neural Repair, 27, 370-380. doi:10.1177/1545968313481284. Link to full text
BACKGROUND: After inpatient stroke rehabilitation, many people still cannot participate in community activities because of limited walking ability.
OBJECTIVE: To compare the effectiveness of 2 conceptually different, early physical therapy (PT) interventions to usual care (UC) in improving walking 6 months after stroke.
METHODS: The locomotor experience applied post-stroke (LEAPS) study was a single-blind, randomized controlled trial conducted in 408 adults with disabling hemiparetic stroke. Participants were stratified at baseline (2 months) by impairment in walking speed: severe (<0.4 m/s) or moderate (0.4 to <0.8 m/s). Between 2 and 6 months, they received either only UC (n = 143) or UC plus 36 therapist-provided sessions of either (1) walking training on a treadmill using body-weight support and practice overground at clinics (locomotor training program [LTP], n = 139) or (2) impairment-based strength and balance exercise at home (home exercise program [HEP], n = 126).
RESULTS: LTP participants were 18% more likely to transition to a higher functional walking level: severe to >0.4 m/s and moderate to >0.8 m/s than UC participants (95% confidence interval [CI] = 7%-29%), and HEP participants were 17% more likely to transition (95% CI = 5%-29%). Mean gain in walking speed in LTP participants was 0.13 m/s greater (95% CI = 0.09-0.18) and in HEP participants, 0.10 m/s greater (95% CI = 0.05-0.14) than in UC participants.
CONCLUSIONS: Progressive PT, using either walking training on a treadmill and overground, conducted in a clinic, or strength and balance exercises conducted at home, was superior to UC in improving walking, regardless of severity of initial impairment.
Wilcox, R. R., Carlson, M. E., Azen, S. P., & Clark, F. A. (2013). Avoid lost discoveries, because of violations of standard assumptions, by using modern robust statistical methods. Journal of Clinical Epidemiology, 66, 319-329. doi:10.1016/j.jclinepi.2012.09.003. Link to full text
OBJECTIVES: Recently, there have been major advances in statistical techniques for assessing central tendency and measures of association. The practical utility of modern methods has been documented extensively in the statistics literature, but they remain underused and relatively unknown in clinical trials. Our objective was to address this issue.
STUDY DESIGN AND PURPOSE: The first purpose was to review common problems associated with standard methodologies (low power, lack of control over type I errors, and incorrect assessments of the strength of the association). The second purpose was to summarize some modern methods that can be used to circumvent such problems. The third purpose was to illustrate the practical utility of modern robust methods using data from the Well Elderly 2 randomized controlled trial.
RESULTS: In multiple instances, robust methods uncovered differences among groups and associations among variables that were not detected by classic techniques. In particular, the results demonstrated that details of the nature and strength of the association were sometimes overlooked when using ordinary least squares regression and Pearson correlation.
CONCLUSION: Modern robust methods can make a practical difference in detecting and describing differences between groups and associations between variables. Such procedures should be applied more frequently when analyzing trial-based data.
Varma, R., Hsu, C., Wang, D., Torres, M., & Azen, S. P. (2013). The Chinese American Eye Study: Design and methods. Ophthalmic Epidemiology, 20, 335-347. doi:10.3109/09286586.2013.823505. Link to full text
PURPOSE: To summarize the study design, operational strategies and procedures of the Chinese American Eye Study (CHES), a population-based assessment of the prevalence of visual impairment, ocular disease, and visual functioning in Chinese Americans.
METHODS: This population-based, cross-sectional study included 4570 Chinese participants aged 50 years and older, residing in the city of Monterey Park, California. Each eligible participant completed a detailed interview and eye examination. The interview included an assessment of demographic, behavioral and ocular risk factors and health-related and vision-related quality of life. The eye examination included measurements of visual acuity, intraocular pressure, visual fields, fundus and optic disc photography, a detailed anterior and posterior segment examination, and measurements of blood pressure, glycosylated hemoglobin levels, and blood glucose levels.
RESULTS: The objectives of the CHES are to obtain prevalence estimates of visual impairment, refractive error, diabetic retinopathy, open-angle and angle-closure glaucoma, lens opacities, and age-related macular degeneration in Chinese Americans. In addition, outcomes include effect estimates for risk factors associated with eye diseases. Lastly, CHES will investigate the genetic determinants of myopia and glaucoma.
CONCLUSION: The CHES will provide information about the prevalence and risk factors of ocular diseases in one of the fastest growing minority groups in the United States.
He, J., Bhasin, S., Binder, E. F., Yarasheski, K. E., Castaneda-Sceppa, C., Schroeder, E. T., Roubenoff, R., Chou, C. P., Azen, S. P., & Sattler, F. R. (2013). Cardiometabolic risks during anabolic hormone supplementation in older men. Obesity, 21, 968-975. doi:10.1002/oby.20081. Link to full text
OBJECTIVE: To determine the cardiometabolic risks of testosterone and growth hormone (GH) replacement therapy to youthful levels during aging.
DESIGN AND METHODS: A double-masked, partially placebo controlled study in 112 men 65-90 years-old was conducted. Transdermal testosterone (5 g vs. 10 g/day) using a Leydig Cell Clamp and subcutaneous recombinant GH (rhGH) (0 vs. 3 vs. 5 μg/kg/day) were administered for 16-weeks. Measurements included testosterone and IGF-1 levels, body composition by DEXA, and cardiometabolic risk factors (upper body fat, blood pressure, insulin sensitivity, fasting triglycerides, HDL-cholesterol, and serum adiponectin) at baseline and after 16 weeks of treatment.
RESULTS: Some cardiometabolic factors improved (total and trunk fat, triglycerides, HDL-cholesterol) and others worsened (systolic blood pressure, insulin sensitivity index [QUICKI], adiponectin). Cardiometabolic risk composite scores (CRCSs) improved (-0.69 ± 1.55, P < 0.001). In multivariate analyses, QUICKI, triglycerides, and HDL-cholesterol contributed 33%, 16%, and 14% of the variance in CRCS, respectively. Pathway analyses indicated that changes in fat and lean mass were related to individual cardiometabolic variables and CRCS in a complex manner. Changes in BMI, reflecting composite effects of changes in fat and lean mass, were more robustly associated with cardiometabolic risks than changes in fat mass or LBM individually.
CONCLUSIONS: Testosterone and rhGH administration was associated with diverse changes in individual cardiometabolic risk factors, but in aggregate appeared not to worsen cardiometabolic risk in healthy older men after 4-months. The long-term effects of these and similar anabolic therapies on cardiovascular events should be investigated in populations with greater functional limitations along with important health disabilities including upper body obesity and other cardiometabolic risks.
Chen, M. A., Kawakubo, M., Colletti, P. M., Xu, D., Dustin, L. L., Detrano, R., Azen, S. P., Wong, N. D., & Zhao, X. Q. (2013). Effect of age on aortic atherosclerosis. Journal of Geriatric Cardiology, 10, 135-140. doi:10.3969/j.issn.1671-5411.2013.02.005. Link to full text
OBJECTIVE: To examine the association of atherosclerosis burden in the survivors of an asymptomatic elderly cohort study and its relationship to other coronary risk factors (specifically, age) by evaluating aortic atherosclerotic wall burden by magnetic resonance imaging (MRI).
METHODS: A total of 312 participants in an ongoing observational cohort study underwent cardiac and descending thoracic aorta imaging by MRI. Maximum wall thickness was measured and the mean wall thickness calculated. Wall/outer wall ratio was used as a normalized wall index (NWI) adjusted for artery size difference among participants. Percent wall volume (PWV) was calculated as NWI × 100.
RESULTS: In this asymptomatic cohort (mean age: 76 years), the mean (SD) aortic wall area and wall thickness were 222 ± 45 mm(2) and 2.7 ± 0.4 mm, respectively. Maximum wall thickness was 3.4 ± 0.6 mm, and PWV was 32% ± 4%. Women appeared to have smaller wall area, but after correcting for their smaller artery size, had significantly higher PWV than men (P = 0.03). Older age was associated with larger wall area (P = 0.04 for trend) with similar PWVs. However, there were no statistically significant associations between standard risk factors, Framingham global risk, or metabolic syndrome status, therapy for cholesterol or hypertension, coronary or aortic calcium score, and the aortic wall burden. Aortic calcification was associated with coronary calcification.
CONCLUSIONS: Asymptomatic elderly in this cohort had a greater descending thoracic aortic wall volume that correlated with age, and women had a significantly increased PWV compared to men. In these survivors, the atherosclerotic aortic wall burden was not significantly associated with traditional risk factors or with coronary or aortic calcium scores or coronary calcium progression. Results suggest that age, or as yet unidentified risk factor(s), may be responsible for the increase in atherosclerosis.
Salem, G. J., Yu, S. S., Wang, M. Y., Samarawickrame, S., Hashish, R., Azen, S. P., & Greendale, G. A. (2013). Physical demand profiles of Hatha yoga postures performed by older adults. Evidence-Based Complementary and Alternative Medicine, 2013, 1-29. doi:10.1155/2013/165763. Link to full text
Understanding the physical demands placed upon the musculoskeletal system by individual postures may allow experienced instructors and therapists to develop safe and effective yoga programs which reduce undesirable side effects. Thus, we used biomechanical methods to quantify the lower extremity joint angles, joint moments of force, and muscle activities of 21 Hatha yoga postures, commonly used in senior yoga programs. Twenty older adults, 70.7 years ± 3.8 years, participated in a 32-wk yoga class (2 d/wk) where they learned introductory and intermediate postures (asanas). They then performed the asanas in a motion analysis laboratory. Kinematic, kinetic, and electromyographic data was collected over three seconds while the participants held the poses statically. Profiles illustrating the postures and including the biomechanical data were then generated for each asana. Our findings demonstrated that Hatha yoga postures engendered a range of appreciable joint angles, JMOFs, and muscle activities about the ankle, knee, and hip, and that demands associated with some postures and posture modifications were not always intuitive. They also demonstrated that all of the postures elicited appreciable rectus abdominis activity, which was up to 70% of that induced during walking.
Winstein, C. J., Wolf, S. L., Dromerick, A. W., Lane, C. J., Nelsen, M. A., Lewthwaite, R., Blanton, S., Scott, C., Reiss, A., Cen, S. Y., Holley, R., & Azen, S. P. (2013). Interdisciplinary Comprehensive Arm Rehabilitation Evaluation (ICARE): A randomized controlled trial protocol. BMC Neurology, 13(5), doi:10.1186/1471-2377-13-5. Link to full text
BACKGROUND: Residual disability after stroke is substantial; 65% of patients at 6 months are unable to incorporate the impaired upper extremity into daily activities. Task-oriented training programs are rapidly being adopted into clinical practice. In the absence of any consensus on the essential elements or dose of task-specific training, an urgent need exists for a well-designed trial to determine the effectiveness of a specific multidimensional task-based program governed by a comprehensive set of evidence-based principles. The Interdisciplinary Comprehensive Arm Rehabilitation Evaluation (ICARE) Stroke Initiative is a parallel group, three-arm, single blind, superiority randomized controlled trial of a theoretically-defensible, upper extremity rehabilitation program provided in the outpatient setting.The primary objective of ICARE is to determine if there is a greater improvement in arm and hand recovery one year after randomization in participants receiving a structured training program termed Accelerated Skill Acquisition Program (ASAP), compared to participants receiving usual and customary therapy of an equivalent dose (DEUCC). Two secondary objectives are to compare ASAP to a true (active monitoring only) usual and customary (UCC) therapy group and to compare DEUCC and UCC.
METHODS/DESIGN: Following baseline assessment, participants are randomized by site, stratified for stroke duration and motor severity. 360 adults will be randomized, 14 to 106 days following ischemic or hemorrhagic stroke onset, with mild to moderate upper extremity impairment, recruited at sites in Atlanta, Los Angeles and Washington, D.C. The Wolf Motor Function Test (WMFT) time score is the primary outcome at 1 year post-randomization. The Stroke Impact Scale (SIS) hand domain is a secondary outcome measure.The design includes concealed allocation during recruitment, screening and baseline, blinded outcome assessment and intention to treat analyses. Our primary hypothesis is that the improvement in log-transformed WMFT time will be greater for the ASAP than the DEUCC group. This pre-planned hypothesis will be tested at a significance level of 0.05.
DISCUSSION: ICARE will test whether ASAP is superior to the same number of hours of usual therapy. Pre-specified secondary analyses will test whether 30 hours of usual therapy is superior to current usual and customary therapy not controlled for dose.
TRIAL REGISTRATION: www.ClinicalTrials.gov Identifier: NCT00871715
Clark, F. A., Jackson, J. M., Carlson, M. E., Chou, C. P., Cherry, B. J., Jordan-Marsh, M., Knight, B. G., Mandel, D., Blanchard, J., Granger, D. A., Wilcox, R. R., Lai, M. Y., White, B. A., Hay, J. W., Lam, C., Marterella, A., & Azen, S. P. (2012). Effectiveness of a lifestyle intervention in promoting the well-being of independently living older people: Results of the Well Elderly 2 Randomised Controlled Trial. Journal of Epidemiology and Community Health, 66, 782-790. doi:10.1136/jech.2009.099754. Link to full text
BACKGROUND: Older people are at risk for health decline and loss of independence. Lifestyle interventions offer potential for reducing such negative outcomes. The aim of this study was to determine the effectiveness and cost-effectiveness of a preventive lifestyle-based occupational therapy intervention, administered in a variety of community-based sites, in improving mental and physical well-being and cognitive functioning in ethnically diverse older people.
METHODS: A randomised controlled trial was conducted comparing an occupational therapy intervention and a no-treatment control condition over a 6-month experimental phase. Participants included 460 men and women aged 60-95 years (mean age 74.9±7.7 years; 53% <$12,000 annual income) recruited from 21 sites in the greater Los Angeles metropolitan area.
RESULTS: Intervention participants, relative to untreated controls, showed more favourable change scores on indices of bodily pain, vitality, social functioning, mental health, composite mental functioning, life satisfaction and depressive symptomatology (ps<0.05). The intervention group had a significantly greater increment in quality-adjusted life years (p<0.02), which was achieved cost-effectively (US $41,218/UK £24,868 per unit). No intervention effect was found for cognitive functioning outcome measures.
CONCLUSIONS: A lifestyle-oriented occupational therapy intervention has beneficial effects for ethnically diverse older people recruited from a wide array of community settings. Because the intervention is cost-effective and is applicable on a wide-scale basis, it has the potential to help reduce health decline and promote well-being in older people.
Carlson, M., Jackson, J., Mandel, D., Blanchard, J., , J. H., Lai, M. Y., Marterella, A., Vigen, C., Gleason, S., Lam, C., Azen, S., & Clark, F. (2012). Predictors of retention among African American and Hispanic older adult research participants in the Well Elderly 2 randomized controlled trial. Journal of Applied Gerontology, 66, 357-382. doi:10.1177/0733464812471444. Link to full text
The purpose of this study was to document predictors of long-term retention among minority participants in the Well Elderly 2 Study, a randomized controlled trial of a lifestyle intervention for community-dwelling older adults. The primary sample included 149 African American and 92 Hispanic men and women aged 60 to 95 years, recruited at senior activity centers and senior residences. Chi-square and logistic regression procedures were undertaken to examine study-based, psychosocial and health-related predictors of retention at 18 months following study entry. For both African Americans and Hispanics, intervention adherence was the strongest predictor. Retention was also related to high active coping and average (vs. high or low) levels of activity participation among African Americans and high social network strength among Hispanics. The results suggest that improved knowledge of the predictors of retention among minority elders can spawn new retention strategies that can be applied at individual, subgroup, and sample-wide levels.
Duncan, P. W., Sullivan, K. J., Behrman, A. L., Azen, S. P., Wu, S. S., Nadeau, S. E., Dobkin, B. H., Rose, D. K., Tilson, J. K., Cen, S., & Hayden, S. K. (2011). Body-weight-supported treadmill rehabilitation after stroke. New England Journal of Medicine, 364(21), 2026-2036.
BACKGROUND: Locomotor training, including the use of body-weight support in treadmill stepping, is a physical therapy intervention used to improve recovery of the ability to walk after stroke. The effectiveness and appropriate timing of this intervention have not been established.
METHODS: We stratified 408 participants who had had a stroke 2 months earlier according to the extent of walking impairment--moderate (able to walk 0.4 to <0.8 m per second) or severe (able to walk <0.4 m per second)--and randomly assigned them to one of three training groups. One group received training on a treadmill with the use of body-weight support 2 months after the stroke had occurred (early locomotor training), the second group received this training 6 months after the stroke had occurred (late locomotor training), and the third group participated in an exercise program at home managed by a physical therapist 2 months after the stroke (home-exercise program). Each intervention included 36 sessions of 90 minutes each for 12 to 16 weeks. The primary outcome was the proportion of participants in each group who had an improvement in functional walking ability 1 year after the stroke.
RESULTS: At 1 year, 52.0% of all participants had increased functional walking ability. No significant differences in improvement were found between early locomotor training and home exercise (adjusted odds ratio for the primary outcome, 0.83; 95% confidence interval [CI], 0.50 to 1.39) or between late locomotor training and home exercise (adjusted odds ratio, 1.19; 95% CI, 0.72 to 1.99). All groups had similar improvements in walking speed, motor recovery, balance, functional status, and quality of life. Neither the delay in initiating the late locomotor training nor the severity of the initial impairment affected the outcome at 1 year. Ten related serious adverse events were reported (occurring in 2.2% of participants undergoing early locomotor training, 3.5% of those undergoing late locomotor training, and 1.6% of those engaging in home exercise). As compared with the home-exercise group, each of the groups receiving locomotor training had a higher frequency of dizziness or faintness during treatment (P=0.008). Among patients with severe walking impairment, multiple falls were more common in the group receiving early locomotor training than in the other two groups (P=0.02).
CONCLUSIONS: Locomotor training, including the use of body-weight support in stepping on a treadmill, was not shown to be superior to progressive exercise at home managed by a physical therapist.
Mazhar, K., Varma, R., Choudhury, F., Mckean-Cowdin, R., Shtir, C. J., & Azen, S. P. (2011). Severity of diabetic retinopathy and health-related quality of life: The Los Angeles Latino Eye Study. Ophthalmology, 118(4), 649-655.
OBJECTIVE: To assess the impact of diabetic retinopathy (DR) and its severity on health-related quality of life (HRQOL) in a population-based sample of Latinos with type 2 diabetes mellitus (DM).
DESIGN: Cross-sectional population-based study, the Los Angeles Latino Eye Study (LALES).
PARTICIPANTS: We included 1064 LALES participants with DM.
METHODS: We measured HRQOL by the 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25) and the Medical Outcomes Study 12-item Short Form Health Survey (SF-12). We assessed DR by masked standardized grading of stereoscopic photographs from 7 standard fields. Severity of DR in eyes was graded using a modified Airlie House classification. The severity scores from each eye were then concatenated to create a single per person grade ranging from 1 (no DR in either eye) to 15 (bilateral PDR). Multiple linear regression analyses were performed to determine the independent relationship between severity of DR and HRQOL after adjusting for covariates.
MAIN OUTCOME MEASURES: Scores on the NEI-VFQ-25 and SF-12.
RESULTS: More severe DR was associated with worse HRQOL scores on all of the NEI-VFQ-25 and SF-12 subscales (P<0.05). Individuals with DR from grade 2 (minimum nonproliferative diabetic retinopathy [NPDR]) through grade 8 (unilateral moderate NPDR) show a modest decline in HRQOL. However, the decline becomes significantly steeper between steps 8 (unilateral moderate NPDR) and 9-15 (bilateral moderate NPDR to bilateral PDR). The domains with the most significant impact were for vision-related daily activities, dependency, and mental health.
CONCLUSIONS: Greater severity of DR was associated with lower general and vision-specific HRQOL. Persons with bilateral moderate NPDR had the most substantial decrease in quality of life compared with those with less severe DR. The prevention of incident DR and, more important, its progression from unilateral to bilateral NPDR is likely to have a positive impact on a person's HRQOL and should be considered an important goal in management of individuals with DM.
Jackson, J. M., Mandel, D., Blanchard, J., Carlson, M. E., Cherry, B. J., Azen, S. P., Chou, C. P., Jordan-Marsh, M., Forman, T., White, B. A., Granger, D., Knight, B. G., & Clark, F. A. (2009). Confronting challenges in intervention research with ethnically diverse older adults: The USC Well Elderly II Trial. Clinical Trials, 6, 90-101.
Community-dwelling older adults are at risk for declines in physical health, cognition, and psychosocial well-being. However, their enactment of active and health-promoting lifestyles can reduce such declines. The purpose of this article is to describe the USC Well Elderly II study, a randomized clinical trial designed to test the effectiveness of a healthy lifestyle program for elders, and document how various methodological challenges were addressed during the course of the trial. In the study, 460 ethnically diverse elders recruited from a variety of sites in the urban Los Angeles area were enrolled in a randomized experiment involving a crossover design component. Within either the first or second 6-month phase of their study involvement, each elder received a lifestyle intervention designed to improve a variety of aging outcomes. At 4-5 time points over an 18-24 month interval, the research participants were assessed on measures of healthy activity, coping, social support, perceived control, stress-related biomarkers, perceived physical health, psychosocial well-being, and cognitive functioning to test the effectiveness of the intervention and document the process mechanisms responsible for its effects. The study protocol was successfully implemented, including the enrollment of study sites, the recruitment of 460 older adults, administration of the intervention, adherence to the plan for assessment, and establishment of a large computerized data base. Methodological challenges were encountered in the areas of site recruitment, participant recruitment, testing, and intervention delivery. The completion of clinical trials involving elders from numerous local sites requires careful oversight and anticipation of threats to the study design that stem from: (a) social situations that are particular to specific study sites; and (b) physical, functional, and social challenges pertaining to the elder population.
Sanossian, N., Wu, J., Azen, S. P., & Varma, R. (2008). Prevalence and risk factors for cerebrovascular disease in community-dwelling Latinos. Clinical Neurology and Neurosurgery, 110(10), 985-987.
OBJECTIVES: Surveys on stroke prevalence may provide valuable information for planning of healthcare services. Few such studies have been conducted in Latinos and none have been performed in Los Angeles, a County that contains the largest population of Latinos in the United States. We sought to assess the prevalence of self-reported stroke in a population-based sample of community-dwelling Latinos in Los Angeles.
PATIENTS AND METHODS: The group comprised of self-identified Latinos aged 40 years and older from six census tracts in Los Angeles participating in a population-based cross-sectional study of ocular disease in Latinos, The Los Angeles Latino Eye Study (LALES). The prevalence of stroke and its association with demographic, biological and behavioral risk factors was determined. Univariate and multiple stepwise logistic regression models were used to calculate odds ratios (ORs).
RESULTS: The prevalence of self-reported stroke in 6954 community-dwelling Latinos in Los Angeles was 3.3%. Stroke prevalence increased with age (1.4% age 40-50, 3.3% age 50-65, 7.1% age >65), history of hypertension (OR 2.6, p<0.001), heart disease (OR 4.8, p<0.001) and diabetic retinopathy (OR 2.1, p=0.01).
CONCLUSIONS: Renewed efforts directed at early identification and treatment of hypertension and heart disease within the Latino community will mitigate the burden of stroke.
Winstein, C. J., Rose, D. K., Tan, S. M., Lewthwaite, R., Chui, H. C., & Azen, S. P. (2004). A randomized controlled comparison of upper-extremity rehabilitation strategies in acute stroke: A pilot study of immediate and long-term outcomes. Archives of Physical Medicine and Rehabilitation, 85(4), 620-628.
OBJECTIVE: To evaluate the immediate and long-term effects of 2 upper-extremity rehabilitation approaches for stroke compared with standard care in participants stratified by stroke severity.
DESIGN: Nonblinded, randomized controlled trial (baseline, postintervention, 9mo) design.
SETTING: Inpatient rehabilitation hospital and outpatient clinic.
PARTICIPANTS: Sixty-four patients with recent stroke admitted for inpatient rehabilitation were randomized within severity strata (Orpington Prognostic Scale) into 1 of 3 intervention groups. Forty-four patients completed the 9-month follow-up.
INTERVENTIONS: Standard care (SC), functional task practice (FT), and strength training (ST). The FT and ST groups received 20 additional hours of upper-extremity therapy beyond standard care distributed over a 4- to 6-week period.
MAIN OUTCOME MEASURES: Performance measures of impairment (Fugl-Meyer Assessment), strength (isometric torque), and function (Functional Test of the Hemiparetic Upper Extremity [FTHUE]).
RESULTS: Compared with SC participants, those in the FT and ST groups had significantly greater increases in Fugl-Meyer motor scores (P=.04) and isometric torque (P=.02) posttreatment. Treatment benefit was primarily in the less severe participants, where improvement in FT and ST group Fugl-Meyer motor scores more than doubled that of the SC group. Similar results were found for the FTHEU and isometric torque. During the long term, at 9 months, the less severe FT group continued to make gains in isometric muscle torque, significantly exceeding those of the ST group (P<.05).
CONCLUSIONS: Task specificity and stroke severity are important factors for rehabilitation of arm use in acute stroke. Twenty hours of upper extremity-specific therapy over 4 to 6 weeks significantly affected functional outcomes. The immediate benefits of a functional task approach were similar to those of a resistance-strength approach, however, the former was more beneficial in the long-term.
Frank, G., Blackhall, L., Murphy, S. T., Michel, V., Azen, S. P., Preloran, H., & Browner, C. (2002). Ambiguity and hope: Disclosure preferences of less acculturated elderly Mexican Americans concerning terminal cancer - A case story. Cambridge Quarterly of Health Care Ethics, 11(2), 117-126.
A major shift has taken place since the 1960s concerning disclosure to patients that they have a diagnosis of cancer and that their disease is considered terminal. Full disclosure is now considered the patient's right in the United States. However, there remain many countries in which nondisclosure is still the norm. When patients from those countries are diagnosed with cancer in America, differences in attitudes and expectations can cause conflict and misunderstanding.
Gilliland, S. S., Azen, S. P., Perez, G. E., & Carter, J. S. (2002). Strong in body and spirit: Lifestyle intervention for Native American adults with diabetes in New Mexico. Diabetes Care, 25(1), 78-83.
OBJECTIVE: To determine the effects of a culturally appropriate diabetes lifestyle intervention for Native Americans on risk factors for complications of diabetes.
RESEARCH DESIGN AND METHODS: A nonrandomized, community-based diabetes intervention trial was conducted in three Native American sites in New Mexico from 1993-1997. Participants were assigned to intervention or control based on community of residence. Intervention sessions were held approximately 6 weeks apart over approximately 10 months. The intervention was delivered in site A in family and friends (FF) groups (n = 32); site B received the same intervention in one-on-one (OO) appointments (n = 39); and site C received usual medical care (UC) (n = 33) (total participants, n = 104). Primary change in HbA(1c) level was assessed at 1 year.
RESULTS: Adjusted mean change in HbA(1c) value varied significantly across the three arms at 1 year (P = 0.05). The UC arm showed a statistically significant increase in adjusted mean HbA(1c) change (1.2%, P = 0.001), whereas both intervention arms showed a small nonsignificant (P > 0.05) increase in the adjusted mean change (0.5% and 0.2% for FF and OO arms, respectively). The increase was statistically significantly smaller in the combined intervention arms (0.4%) compared with the UC arm (1.2%, P = 0.02).
CONCLUSIONS: Lifestyle intervention has the potential to substantially reduce microvascular complications, mortality, and health care utilization and costs if the change is sustained over time.
Hay, J., LaBree, L., Luo, R., Clark, F. A., Carlson, M. E., Mandel, D., Zemke, R., Jackson, J. M., & Azen, S. P. (2002). Cost-effectiveness of preventive occupational therapy for independent-living older adults. Journal of the American Geriatrics Society, 50(8), 1381-1388.
OBJECTIVES:To evaluate the cost-effectiveness of a 9-month preventive occupational therapy (OT) program in the Well-Elderly Study: a randomized trial in independent-living older adults that found significant health, function, and quality of life benefits attributable to preventive OT.
DESIGN:A randomized trial.
SETTING:Two government-subsidized apartment complexes.
PARTICIPANTS:One hundred sixty-three culturally diverse volunteers aged 60 and older.
INTERVENTION:An OT group, a social activity group (active control), and a nontreatment group (passive control).
MEASUREMENTS:Use of healthcare services was determined by telephone interview during and after the treatment phase. A conversion algorithm was applied to the RAND 36-item Short Form Health Survey to derive a preference-based health-related quality of life index, quality-adjusted life years (QALYs), and the incremental cost-effectiveness ratio for preventive OT relative to the combined control group.
RESULTS:Costs for the 9-month OT program averaged $548 per subject. Postintervention healthcare costs were lower for the OT group ($967) than for the active control group ($1,726), the passive control group ($3,334), or a combination of the control groups ($2,593). The quality of life index showed a 4.5% QALY differential (OT vs combined control), P < .001. The cost per QALY estimates for the OT group was $10,666 (95% confidence interval = $6,747–$25,430). For the passive and active control groups, the corresponding costs per QALY were $13,784 and $7,820, respectively.
CONCLUSION:In this study, preventive OT demonstrated cost-effectiveness in conjunction with a trend toward decreased medical expenditures.
Clark, F. A., Azen, S. P., Carlson, M. E., Mandel, D., LaBree, L., Hay, J., Zemke, R., Jackson, J. M., & Lipson, L. (2001). Embedding health-promoting changes into the daily lives of independent-living older adults: Long-term follow-up of occupational therapy intervention. Journal of Gerontology: Psychological Sciences and Social Sciences, 56B, 60-63.
The Well Elderly Study was a randomized trial in independent-living older adults that found significant health, function, and quality of life benefits attributable to a 9-month program in preventive occupational therapy (OT). All participants completing the trial were followed for an additional 6 months without further intervention and then reevaluated using the same battery of instruments. Long-term benefit attributable to preventive OT was found for the quality of interaction scale of the Functional Status Questionnaire and for six of eight scales on the RAND SF-36: physical functioning, role functioning, vitality, social functioning, role emotional, and general mental health (p < .05). Approximately 90% of the therapeutic gain observed following OT treatment was retained in follow-up. The finding of a sustained effect for preventive OT is of great public health relevance given the looming health care cost crisis associated with our nation's expanding elderly population.
Jackson, J. M., Kennedy, B. L., Mandel, D., Carlson, M. E., Cherry, B., Fanchiang, S., Ding, L., Zemke, R., Azen, S. P., LaBree, L., & Clark, F. A. (2000). Derivation and pilot assessment of a health promotion program for Mandarin-speaking Chinese older adults. The International Journal of Aging & Human Development, 50(2), 127-149.
Describes methods used to adapt a health care program so that it would better meet the needs of a group of well, older Mandarin-speaking Chinese residents of Los Angeles. Outcomes from a pilot experiment are presented that are consistent with the notion that the adapted program was effective in reducing health-related declines among participants.
Blackhall, L., Frank, G., Murphy, S. T., Michel, V., Palmer, J., & Azen, S. P. (1999). Ethnicity and attitudes towards life sustaining technology. Social Science and Medicine, 48(12), 1779-1789.
The ethical and legal implications of decisions to withhold and withdraw life support have been widely debated. Making end-of-life decisions is never easy, and when the cultural background of doctor and patient differ, communication about these issues may become even more difficult. In this study, we examined the attitudes of people aged 65 and older from different ethnic groups toward foregoing life support. To this end, we conducted a survey of 200 respondents from each of four ethnic groups: European-American, African-American, Korean-American and Mexican-American (800 total), followed by in-depth ethnographic interviews with 80 respondents. European-Americans were the least likely to both accept and want life-support (p < 0.001). Mexican-Americans were generally more positive about the use of life-support and were more likely to personally want such treatments (p < 0.001). Ethnographic interviews revealed that this was due to their belief that life-support would not be suggested if a case was truly hopeless. Compared to European-Americans, Korean-Americans were very positive regarding life-support (RR = 6.7, p < 0.0001); however, they did not want such technology personally (RR = 1.2, p = 0.45). Ethnographic interviews revealed that the decision of life support would be made by their family. Compared to European-Americans, African-Americans felt that it was generally acceptable to withhold or withdraw life-support (RR = 1.6, p = 0.06), but were the most likely to want to be kept alive on life-support (RR = 2.1, p = 0.002). Ethnographic interviews documented a deep distrust towards the health care system and a fear that health care was based on one's ability to pay. We concluded that (a) ethnicity is strongly related to attitudes toward and personal wishes for the use of life support in the event of coma or terminal illness, and (b) this relationship was complex and in some cases, contradictory.
Azen, S. P., Palmer, J., Carlson, M. E., Jackson, J. M., Cherry, B., Fanchiang, S., & Clark, F. A. (1999). Psychometric properties of a Chinese translation of the SF-36 Health Survey Questionnaire in the well elderly study. Journal of Aging and Health, 11(2), 240-251.
This study seeks to evaluate the psychometric properties of a Chinese translation of the 36-item Short Form Health Survey (SF-36) in the Well Elderly Study: a randomized clinical trial designed to evaluate the effectiveness of preventive occupational therapy services specifically tailored for multiethnic, independent-living, older adults. Translation and back-translation procedures were used to obtain appropriate meanings for the SF-36 survey questions and to ensure face, functional, and conceptual equivalence. Statistical analyses demonstrated satisfactory reliability and validity, with the results generally similar to those reported for older Anglo adults. As the percentage of older adults of diverse ethnicity increases, the need for health care research and service strategies that can effectively include multiple ethnicities becomes paramount. The results of this study suggest that a Chinese translated SF-36 can be used to assess multiple dimensions of health in a Mandarin-speaking population of older adults.
Frank, G., Blackhall, L., Michel, V., Murphy, S. T., Azen, S. P., & Park, K. (1998). A discourse of relationships in bioethics: Patient autonomy and end-of-life decision-making among elderly Korean-Americans. Medical Anthropology Quarterly, 12(4), 403-423.
A two-year, multidisciplinary study (N = 800) was conducted on attitudes about end-of-life decision making among elderly individuals in four ethnic groups (African American, European American, Korean American, and Mexican American). On a quantitative survey, Korean Americans reported negative attitudes about the use of life-sustaining technology for themselves but positive attitudes about its use in general. This article reports on an interview with a 79-year-old typical Korean American respondent to explain the contradiction in the survey data. Expectations among elderly Korean Americans include protecting family members with a life-threatening illness from being informed of their diagnosis and prognosis, and doing everything to keep them alive. Two conclusions, one substantive and the other methodological, are drawn: First, the bioethics discourse on individual rights (patientautonomy) is insufficient to explain the preferences of many Korean Americans and must be supplemented with a discourse on relationships. Second, the rigorous use of qualitative, narrative methods clarifies quantitative data and should not be dismissed as "anecdotal." fbioethics, endof- life decision making, ethnicity, Asian Americans, qualitative methods, narrative]
Clark, F. A., Azen, S. P., Zemke, R., Jackson, J. M., Carlson, M. E., Hay, J., Mandel, D., Josephson, K., Cherry, B., Hessel, C., Palmer, J., & Lipson, L. (1997). Occupational therapy for independent-living older adults: A randomized controlled trial. Journal of the American Medical Association, 278(16), 1321-1326. Link to full text
Preventive health programs may mitigate against the health risks of older adulthood. OBJECTIVE: To evaluate the effectiveness of preventive occupational therapy (OT) services specifically tailored for multiethnic, independent-living older adults. Design.-A randomized controlled trial. SETTING: Two government subsidized apartment complexes for independent-living older adults. SUBJECTS: A total of 361 culturally diverse volunteers aged 60 years or older. INTERVENTION: An OT group, a social activity control group, and a nontreatment control group. The period of treatment was 9 months. MAIN OUTCOME MEASURES: A battery of self-administered questionnaires designed to measure physical and social function, self-rated health, life satisfaction, and depressive symptoms. RESULTS: Benefit attributable to OT treatment was found for the quality of interaction scale on the Functional Status Questionnaire (P=.03), Life Satisfaction Index-Z (P=.03), Medical Outcomes Study Health Perception Survey (P=.05), and for 7 of 8 scales on the RAND 36-Item Health Status Survey, Short Form: bodily pain (P=.03), physical functioning (P=.008), role limitations attributable to health problems (P=.02), vitality (P=.004), social functioning (P=.05), role limitations attributable to emotional problems (P=.05), and general mental health (P=.02). CONCLUSIONS: Significant benefits for the OT preventive treatment group were found across various health, function, and quality-of-life domains. Because the control groups tended to decline over the study interval, our results suggest that preventive health programs based on OT may mitigate against the health risks of older adulthood.
Murphy, S. T., Palmer, J., Azen, S. P., Frank, G., Michel, V., & Blackhall, L. (1996). Ethnicity and advance care directives. Journal of Law, Medicine & Ethics, 24(2), 108-117.
Blackhall, L., Murphy, S., Frank, G., Michel, V., & Azen, S. P. (1995). Ethnicity and attitudes toward patient autonomy. Journal of the American Medical Association, 274(10), 820-825.
OBJECTIVE--To study differences in the attitudes of elderly subjects from different ethnic groups toward disclosure of the diagnosis and prognosis of a terminal illness and toward end-of-life decision making. DESIGN--Survey. SETTING--Thirty-one senior citizen centers within Los Angeles County, California. RESPONDENTS--A stratified quota sample of 200 subjects aged 65 years and older self-identified as being from each of four ethnic groups: European American, African American, Korean American, or Mexican American (N = 800). MAIN OUTCOME MEASURES AND RESULTS--Korean Americans (47%) and Mexican Americans (65%) were significantly less likely than European Americans (87%) and African Americans (88%) to believe that a patient should be told the diagnosis of metastatic cancer. Korean Americans (35%) and Mexican Americans (48%) were less likely than African Americans (63%) and European Americans (69%) to believe that a patient should be told of a terminal prognosis and less likely to believe that the patient should make decisions about the use of life-supporting technology (28% and 41% vs 60% and 65%). Instead, Korean Americans and Mexican Americans tended to believe that the family should make decisions about the use of life support. On stepwise multiple logistic regression, ethnicity was the primary factor related to attitudes toward truth telling and patient decision making. CONCLUSIONS--Korean-American and Mexican-American subjects were more likely to hold a family-centered model of medical decision making rather than the patient autonomy model favored by most of the African-American and European-American subjects. This finding suggests that physicians should ask their patients if they wish to receive information and make decisions or if they prefer that their families handle such matters.
Saeki, K., Clark, F. A., & Azen, S. P. (1985). Performance of Japanese and Japanese-American children on the Motor Accuracy Revised and Design Copying Test: A cross-cultural study. American Journal of Occupational Therapy, 39(2), 103-109. Link to full text
This study investigates whether cultural differences affect childrens' performances on the Design Copying (DC) and Motor Accuracy-Revised (MAC-R) Tests of the Southern California Sensory Integration Tests. The DC and the MAC-R were administered to 98 children who were born in Japan and lived there at least during the first year of life and to 82 children who were of Japanese descent but who were born in America. Average test scores of the Japanese and Japanese-American children were compared with those of the American children, on whom the tests were standardized. Results of the tests requiring right-hand performance revealed that both groups of Japanese-descent children performed better than the standardization group of American children; the Japan-born children performed the best. We base these findings on the influence that culture has on the development of a child.
Shuer, J., Clark, F. A., & Azen, S. P. (1980). Vestibular function in mildly mentally retarded adults. American Journal of Occupational Therapy, 34(10), 664-670. Link to full text
The purpose of this study was to compare the duration of nystagmus in mildly mentally retarded and normal adults as measured by the Southern California Postrotary Nystagmus Test. The results revealed that the retarded males demonstrated attenuated duration of nystagmus. These findings support the need for further investigation of possible sensory integrative deficits in this population so that proper treatment can be provided.
Clark, F. A., Miller, L., Thomas, J., Kucherawy, D., & Azen, S. P. (1978). A comparison of operant and sensory integrative methods on developmental parameters in profoundly retarded adults. American Journal of Occupational Therapy, 32, 86-92.