Objectives

To assess the correspondence between self-reported and measured indicators of mobility disability in older adults in six low- and middle-income countries (LMICs).

Design

Cross-sectional analysis of Study on Global AGEing and Adult Health (SAGE).

Setting

Household surveys in China, India, Russia, South Africa, Ghana, and Mexico.

Participants

Community-dwelling SAGE respondents aged 65 and older (N = 12,215).

Measurements

Objective mobility was assessed according to a 4-m timed walk at normal pace conducted in the respondent's home; slow walking speed was defined according to the Fried frailty criteria (lowest quintile of walking speed, adjusted for age and height). Self-reported mobility difficulty was assessed according to a question about ability to walk 1 km; this response was dichotomized into any versus no self-reported difficulty walking 1 km (reference no difficulty). The age- (5-year groups) and sex-specific probability of self-reporting difficulty walking 1 km was estimated in those with a measured slow walk using logistic regression.

Results

Between 42% and 76% of people aged 65 and older reported any difficulty walking 1 km. Average walking speed was slowest in Russia (0.61 m/s) and fastest in China (0.88 m/s). The probabilities of reporting any difficulty walking 1 km in women aged 65 to 69, for example, with a slow walk varied (China = 0.35, India = 0.90, Russia = 0.68, South Africa = 0.81, Ghana = 0.91, Mexico = 0.73; test of country differences P < .001). There was significant variation at older ages, albeit smaller in magnitude. Patterns were similar for men.

Conclusion

Although correspondence between an objective and self-reported measure of mobility was generally high, correspondence differed significantly between LMICs. International comparisons of self-reported disability measures for clinical, prevention, and policy guidelines in LMICs should consider that self-reported data may not correspond to objective measures uniformly between countries.

Objectives

To compare typical age-related changes in activities of daily living (ADLs) independence in stroke-free adults with long-term ADL trajectories before and after stroke.

Design

Prospective, observational study.

Setting

Community-dwelling Health and Retirement Study (HRS) cohort.

Participants

HRS participants who were stroke free in 1998 and were followed through 2008 (average follow-up 7.9 years) (N = 18,441).

Measurements

Strokes were assessed using self- or proxy-report of a doctor's diagnosis and month and year of event. Logistic regression was used to compare within-person changes in odds of self-reported independence in five ADLs in those who remained stroke free throughout follow-up (n = 16,816), those who survived a stroke (n = 1,208), and those who had a stroke and did not survive to participate in another interview (n = 417). Models were adjusted for demographic and socioeconomic covariates.

Results

Even before stroke, those who later developed stroke had significantly lower ADL independence and were experiencing faster independence losses than similar-aged individuals who remained stroke free. Of those who developed a stroke, survivors experienced slower pre-stroke loss of ADL independence than those who died. ADL independence declined at the time of stroke and decline continued afterwards.

Conclusion

In adults at risk of stroke, disproportionate ADL limitations emerge well before stroke onset. Excess disability in stroke survivors should not be entirely attributed to effects of acute stroke or quality of acute stroke care. Although there are many possible causal pathways between ADL and stroke, the association may be noncausal. For example, ADL limitations may be a consequence of stroke risk factors (e.g., diabetes mellitus) or early cerebrovascular ischemia.

Although depressive symptoms have been linked to stroke, most research has been in relatively ethnically homogeneous, predominantly white, samples. Using the United States based Health and Retirement Study, we compared the relationships between elevated depressive symptoms and incident first stroke for Hispanic, black, or white/other participants (N = 18,648) and estimated the corresponding Population Attributable Fractions. The prevalence of elevated depressive symptoms was higher in blacks (27%) and Hispanics (33%) than whites/others (18%). Elevated depressive symptoms prospectively predicted stroke risk in the whites/other group (HR = 1.53; 95% CI: 1.36-1.73) and among blacks (HR = 1.31; 95% CI: 1.05-1.65). The HR was similar but only marginally statistically significant among Hispanics (HR = 1.33; 95% CI: 0.92-1.91). The Population Attributable Fraction, indicating the percent of first strokes that would be prevented if the incident stroke rate in those with elevated depressive symptoms was the same as the rate for those without depressive symptoms, was 8.3% for whites/others, 7.8% for blacks, and 10.3% for Hispanics.