Self-reported Physical Disability Research Articles

Isometric muscle strength is an indicator of self-reported physical functional disability in patients with rheumatoid arthritis.

The objective of our study was to examine (1) whether isometric muscle strength contributes to the explanation of the physical functional disability of a rheumatoid arthritis (RA) patient population after accounting for other disease parameters and demographic variables and (2) whether change in isometric muscle strength is an indicator of change in physical functional disability. Sixty-five consecutive patients fulfilling the American Rheumatism Association 1987 revised criteria for RA were included in the study. Isometric muscle strength was measured with a validated Muscle Strength Index (MSI) calculated as the mean score of standardized isometric extension and flexion strength of the knee and elbow joints. Physical functional disability was measured with the physical dimension of the Health Assessment Questionnaire (HAQ). For 56 patients, we could obtain 1 yr follow-up data. Cross-sectionally, there was a significant correlation (r = -0.51, P < 0.01) between the MSI and the HAQ. Muscle strength remained a significant determinant of the HAQ in multivariate analysis accounting for disease and demographic variables. Longitudinally, change in MSI explained additional variance of change in HAQ after accounting for change in pain, the most important correlate of change in HAQ.

Body fat and skeletal muscle mass in relation to physical disability in very old men and women of the Framingham Heart Study.

Low muscle mass has been assumed to be associated with disability, but no studies confirming this association have been published. High body weight and high body mass index, both rough indicators of body fatness, have been shown to increase the risk for disability; however, the specific role of body fatness has not been studied. The relations of skeletal muscle mass and percent body fat with self-reported physical disability were studied in 753 men and women aged 72 to 95 years. Cross-sectional data from biennial examination 22 (1992-1993) of the Framingham Heart Study were used. Body composition was assessed by dual-energy x-ray absorptiometry. Disability was scored as any versus none on a 9-item questionnaire. Total body and lower extremity muscle mass were not associated with disability in either men or women. However, a strong positive association between percent body fat and disability was observed. The odds ratio for disability in those in the highest tertile of body fatness was 2.69 (95% confidence interval 1.45-5.00) for women and 3.08 (1.22-7.81) for men compared to those in the lowest tertile. The increased risk could not be explained by age, education, physical activity, smoking, alcohol use, estrogen use (women only), muscle mass, and health status. Analyses restricting disability to mobility items gave similar results. In contrast to current assumptions, low skeletal muscle mass was not associated with self-reported physical disability. Persons with a high percent body fat had high levels of disability. Because it cannot be ruled out that persons with low skeletal muscle mass dropped out earlier in the study, prospective studies are needed to further assess the relationship between body composition and physical disability.

A Randomized Trial Comparing Aerobic Exercise and Resistance Exercise With a Health Education Program in Older Adults With Knee Osteoarthritis

To determine the effects of structured exercise programs on self-reported disability in older adults with knee osteoarthritis. A randomized, single-blind clinical trial lasting 18 months conducted at 2 academic medical centers. A total of 439 community-dwelling adults, aged 60 years or older, with radiographically evident knee osteoarthritis, pain, and self-reported physical disability. An aerobic exercise program, a resistance exercise program, and a health education program. The primary outcome was self-reported disability score (range, 1-5). The secondary outcomes were knee pain score (range, 1-6), performance measures of physical function, x-ray score, aerobic capacity, and knee muscle strength. A total of 365 (83%) participants completed the trial. Overall compliance with the exercise prescription was 68% in the aerobic training group and 70% in the resistance training group. Postrandomization, participants in the aerobic exercise group had a 10% lower adjusted mean (+/- SE) score on the physical disability questionnaire (1.71 +/- 0.03 vs 1.90 +/- 0.04 units; P<.001), a 12% lower score on the knee pain questionnaire (2.1 +/- 0.05 vs 2.4 +/- 0.05 units; P=.001), and performed better (mean [+/- SE]) on the 6-minute walk test (1507 +/- 16 vs 1349 +/- 16 ft; P<.001), mean (+/-SE) time to climb and descend stairs (12.7 +/- 0.4 vs 13.9 +/- 0.4 seconds; P=.05), time to lift and carry 10 pounds (9.1 +/- 0.2 vs 10.0 +/- 0.1 seconds; P<.001), and mean (+/-SE) time to get in and out of a car (8.7 +/- 0.3 vs 10.6 +/- 0.3 seconds; P<.001) than the health education group. The resistance exercise group had an 8% lower score on the physical disability questionnaire (1.74 +/- 0.04 vs 1.90 +/- 0.03 units; P=.003), 8% lower pain score (2.2 +/- 0.06 vs 2.4 +/- 0.05 units; P=.02), greater distance on the 6-minute walk (1406 +/- 17 vs 1349 +/- 16 ft; P=.02), faster times on the lifting and carrying task (9.3 +/- 0.1 vs 10.0 +/- 0.16 seconds; P=.001), and the car task (9.0 +/- 0.3 vs 10.6 +/- 0.3 seconds; P=.003) than the health education group. There were no differences in x-ray scores between either exercise group and the health education group. Older disabled persons with osteoarthritis of the knee had modest improvements in measures of disability, physical performance, and pain from participating in either an aerobic or a resistance exercise program. These data suggest that exercise should be prescribed as part of the treatment for knee osteoarthritis.

Psychiatric interview and psychometric predictors of cardiac transplant survival.

This study prospectively investigated the relation between pretransplant assessment of psychiatric diagnosis, coping skills, and social support and outcome measures of survival and health care utilization. Ninety-four heart transplant patients underwent structured interviews and completed a battery of self-report psychometric tests assessing coping style, health status, and psychosocial supports. Follow-up that ranged from 9 to 56 months after transplant produced a group of 63 survivors and 31 nonsurvivors, who were found to be comparable in terms of pretransplant cardiac status and severity of illness. Survival analysis showed that dimensional psychometric measures of coping and social support based on patient self-assessment were the best significant predictors of survival. Considered separately, interview-determined ratings of social support and pretransplant compliance with treatment regimens were also potential predictors. Formal DSM-III-R diagnoses were related specifically to posttransplant hospital utilization (axis I diagnoses) and posttransplant health behavior (axis II diagnoses). The data demonstrate the value of multifaceted assessment, since psychiatric diagnosis, coping style, and psychosocial support may contribute differently to prediction of such aspects of outcome as mortality and health care utilization.

Minority advantage in diabetic end-stage renal disease survival on hemodialysis: Due to different proportions of diabetic type?

The objectives of this study were to identify predictors of survival on hemodialysis in patients with diabetic end-stage renal disease (ESRD) and to explain ethnic differences in survival among non-Hispanic whites, African-Americans, and Mexican-Americans. The study design was a survival analysis of an inception cohort and was conducted in dialysis centers in two urban counties in Texas. A population-based, tri-ethnic cohort of 638 adult patients with diabetic ESRD were studied. Follow-up was completed in 96% of the cohort, with a median length of follow-up of 3.8 years. Survival length on center hemodialysis was the main outcome measure. In a combined model of types I and II diabetes, Mexican-Americans (relative hazard [rh], 0.666; 95% confidence interval [ci], 0.457 to 0.944) and African-Americans (RH, 0.598; 95% Cl, 0.414 to 0.864) showed a better survival than non-Hispanic whites. Other predictors independently associated with survival were age (RH,1.015 per 10 years of age; 95% Cl, 1.001 to 1.028), high self-reported physical disability (RH, 1.770; 95% Cl, 1.213 to 2.583), coronary artery disease (RH, 1.445; 95% Cl, 1.044 to 2.012), lower extremity amputations (RH, 2.049; 95% Cl, 1.438 to 2.920), and average blood glucose levels prior to ESRD (RH, 1.002 per 1 mg/dL increment; 95% Cl, 1.003 to 1.004). Non-Hispanic whites had a significantly higher rate of type I diabetes, but did not have a greater burden of any of the other predictors. In separate type I and II models, ethnicity was still a significant predictor of survival among type I but not among type II. In conclusion, we have reconfirmed the survival advantage on dialysis of African-Americans and Mexican-Americans over non-Hispanic whites with diabetic ESRD. However, among type II patients, this minority survival advantage disappears. Self-reported physical disability is an important predictor of survival among both diabetes types. Functional status at baseline is an important predictor of survival and should be assessed as an adjunct to measurement of co-morbidities. Macrovascular disease is important for type II, while educational status is important for type I. While amputation may be a marker for the severity of systemic illness, it could be a marker for quality of primary care provided to diabetic patients, since a majority of diabetic lower extremity amputations are thought to be preventable.

Sensory impairments and physical disability in aged women living at home.

Studies of the impact of visual or hearing impairments on physical disability in older people have provided conflicting results. Furthermore, the consequences of the loss of such visual functions as depth perception or contrast sensitivity have rarely been studied. We examined the relationship of visual acuity, depth perception, contrast sensitivity, and hearing difficulty to the ability of older women living at home to accomplish instrumental activities of daily living independently. Data on self-reported physical disability and hearing impairment, as well as objective measures of functional vision and physical ability were collected from a sample of 1210 community-dwelling women aged 75 years and older. Multivariate logistic regression modelling was used to assess the strength of the association between physical disability and sensory impairments, controlling for age, education level, motor limitations, and prevalent chronic diseases. Women with low visual acuity or low contrast sensitivity were significantly more likely to be physically dependent than women with good vision. Contrast sensitivity was, however, a better predictor than functional acuity, after controlling for age, education level, motor limitations and chronic medical conditions (adjusted odds ratio: 5.1; 95% confidence interval: 2.0-12.9). Depth perception was not related to physical disability. Women with serious hearing difficulty had significantly increased odds of dependency (4.1; 1. 4-12.1). Severe sensory impairments are strongly related to physical dependency in older women. It may be useful to add a test of contrast sensitivity to the traditional acuity test to predict better which elderly individuals may have difficulty carrying out routine daily activities.