Life-Space Mobility and Cognitive Decline Among Mexican Americans Aged 75 Years and Older.

OBJECTIVES

To examine the association between life-space mobility and cognitive decline over a five-year period among older Mexican Americans.

DESIGN

Longitudinal study.

SETTING

Hispanic Established Population for the Epidemiologic Study of the Elderly survey conducted in the southwestern of United States (Texas, Colorado, Arizona, New Mexico, and California).

PARTICIPANTS

Four hundred thirty-two Mexican Americans aged 75 and older with normal or high cognitive function at baseline.

MEASUREMENTS: Socio-demographic factors, living arrangement, type of household, social support, financial strain, self-reported medical conditions, Mini-Mental State Examination (MMSE), depressive symptoms, activities of daily living (ADLs), and Short Physical Performance Battery. Life-space assessment (LSA) during the past 4 weeks was assessed during in-home interview. Scores ranged from 0 (daily restriction to the bedroom) to 120 (daily trips outside of their own town without assistance) and categorized as 0 to 20, 21 to 40, 41 to 60, 61 to 80, and 81 to 120. Because of the small sample size in the category of 81 to 120, the two highest categories were combined into a single group.

RESULTS

The mean LSA score and MMSE score of participants at baseline was 44.6 (Standard Deviation [SD], 20.7) and 25.7 (SD, 3.2), respectively. Mixed Model analyses showed that participants in the highest life-space category (≥61) experienced slower rates of cognitive decline over time compared to participants in the lowest category (0 to 20) (β = 1.03, Standard Error [SE] = 0.29, P = 0.0004), after adjusting for all covariates.

CONCLUSION

Greater life-space mobility at baseline was predictor of slower rates of cognitive decline over 5 years in older Mexican Americans.