Purpose in life and reduced incidence of stroke in older adults: 'The Health and Retirement Study'
Objective: To determine whether purpose in life is associated with reduced stroke incidence among older adults after adjusting for relevant sociodemographic, behavioral, biological, and psychosocial factors. Methods: We used prospective data from the Health and Retirement Study, a nationally representative panel study of American adults over the age of 50. 6739 adults who were stroke-free at baseline were examined. A multiple imputation technique was used to account for missing data. Purpose in life was measured using a validated adaptation of Ryff and Keyes' Scales of Psychological Well-Being. After controlling for a comprehensive list of covariates, we assessed the odds of stroke incidence over a four-year period. We used psychological and covariate data collected in 2006, along with occurrences of stroke reported in 2008, 2010, and during exit interviews. Covariates included sociodemographic factors (age, gender, race/ethnicity, marital status, education level, total wealth, functional status), health behaviors (smoking, exercise, alcohol use), biological factors (hypertension, diabetes, systolic blood pressure, diastolic blood pressure, BMI, heart disease), negative psychological factors (depression, anxiety, cynical hostility, negative affect), and positive psychological factors (optimism, positive affect, and social participation). Results: Greater baseline purpose in life was associated with a reduced likelihood of stroke during the four-year follow-up. In a model that adjusted for age, gender, race/ethnicity, marital status, education level, total wealth, and functional status, each standard deviation increase in purpose was associated with a multivariate-adjusted odds ratio of 0.78 for stroke (95% CI, 0.67-0.91, p=.002). Purpose remained significantly associated with a reduced likelihood of stroke after adjusting for several additional covariates including: health behaviors, biological factors, and psychological factors. Conclusion: Among older American adults, greater purpose in life is linked with a lower risk of stroke.