Volunteering, driving status, and mortality in U.S. retirees.

OBJECTIVES: To evaluate how accounting for driving status altered the relationship between volunteering and mortality in U.S. retirees.

DESIGN: Observational prospective cohort.

SETTING: Nationally representative sample from the Health and Retirement Study in 2000 and 2002 followed to 2006.

PARTICIPANTS: Retirees aged 65 and older (N=6,408).

MEASUREMENTS: Participants self-reported their volunteering, driving status, age, sex, race or ethnicity, presence of chronic conditions, geriatric syndromes, socioeconomic factors, functional limitations, and psychosocial factors. Death by December 31, 2006, was the outcome.

RESULTS: For drivers, mortality in volunteers (9%) and nonvolunteers (12%) was similar; for limited or non-drivers, mortality for volunteers (15%) was markedly lower than for nonvolunteers (32%). Adjusted results showed that, for drivers, the volunteering-mortality odds ratio (OR) was 0.90 (95% confidence interval (CI)=0.66-1.22), whereas for limited or nondrivers, the OR was 0.62 (95% CI=0.49-0.78) (interaction P=.05). The effect of driving status was greater for rural participants, with greater differences between rural drivers and rural limited or nondrivers (interaction P=.02) and between urban drivers and urban limited or nondrivers (interaction P=.81).

CONCLUSION: The influence of volunteering in decreasing mortality seems to be stronger in rural retirees who are limited or nondrivers. This may be because rural or nondriving retirees are more likely to be socially isolated and thus receive more benefit from the greater social integration from volunteering.