December 5, 2011
Depressive symptoms linked to limited mobility in older blacks
Study links mobility loss in older African-Americans to initial mobility status
A new study led by researchers at the Johns Hopkins Bloomberg School of Public Health and featured in a 2011 issue of the Journal of Gerontology has identified demographic and health-related characteristics that were related to mobility limitation.
Investigators found that African-American women who reported major depressive symptoms had nearly three times the odds of mobility limitation than those without major depressive symptoms. In addition, African-Americans who reported two or more medical conditions had higher odds of mobility impairment than those who reported fewer medical conditions. The new study has implications for members of the aging baby boomer population, in light of previous studies that have suggested that impaired mobility is a precursor to adverse events in older adults such as hospitalizations and nursing home admissions.
“The rapidly growing U.S. population 65 and older will bring with it greater numbers of minorities and people with mobility challenges,” said Roland Thorpe, an assistant scientist in the Bloomberg School’s Department of Health Policy and Management. “Major depressive symptoms have not been previously identified as a factor of mobility difficulty, but these findings suggest that apathy may play a role in this relationship. It’s possible participants could do the measured activities, such as walking or climbing stairs, but lacked the motivation to do so. Strategies to preserve mobility among African-Americans must include efforts to reduce major depressive symptoms and proper health care to treat and control medical conditions such as diabetes, heart trouble, arthritis and stroke,” he said.
Researchers identified demographic and health-related characteristics that were related to mobility limitation in a sample of 602 African-Americans. Participants included men and women between the ages of 48 and 92 who reported being limited in climbing one flight of stairs or walking several blocks. Thorpe and colleagues conducted logistic regression to estimate the independent effect of each demographic and health-related characteristic on odds of mobility limitation. They found that among African-Americans, co-morbid conditions were associated with mobility limitation, and women with lower incomes were most affected.
In a second study, published in a separate issue of the Journal of Gerontology, Thorpe led a team of researchers who examined the relationship between race and mobility to evaluate how socioeconomic status indicators, such as education and poverty level, affect this relationship. Using data from the Health, Aging and Body Composition Study, researchers examined black and white participants between the ages of 70 and 79 who self-reported capacity to walk a quarter-mile and climb 10 steps at a reasonable pace. In initially well-functioning older adults, blacks had poorer mobility status based on walking speed compared to whites, a difference that was not explained by poverty, education, reading level or income adequacy. Over five years, black men experienced greater mobility limitation than white men.
“Higher rates of mobility loss observed in older blacks relative to older whites appear to be a function of poorer initial mobility status and existing health conditions, particularly for women,” Thorpe said. “Education may also play a role, especially for men.”
“Correlates of Mobility Limitation in African-Americans” was written by Thorpe, Olivio J. Clay, Sarah L. Szanton, Jason C. Allaire and Keith E. Whitefield. The study was supported in part by the National Institute on Aging and the National Center for Minority Health and Health Disparities.
“Race, Socioeconomic Resources, and Late-Life Mobility and Decline: Findings From the Health, Aging and Body Composition Study” was written by Thorpe, Annemarie Koster, Stephen B. Kritchevsky, Anne B. Newman, Tamara Harris, Hilsa N. Ayonayon, Sara Perry, Ronica N. Rooks and Eleanor M. Simonsick. The study was supported in part by the National Institute on Aging, the Intramural Research Program of the National Institutes of Health and the National Center for Minority Health and Health Disparities.