Sense of purpose in life and allostatic load in two longitudinal cohorts

OBJECTIVE: Sense of purpose in life has been linked with better physical health, longevity, and reduced risk for disability and dementia, but the mechanisms linking sense of purpose with diverse health outcomes are unclear. Sense of purpose may promote better physiological regulation in response to stressors and health challenges, leading to lower allostatic load and disease risk over time. The current study examined the association between sense of purpose in life and allostatic load over time in adults over age 50. METHODS: Data from the nationally representative US Health and Retirement Study (HRS) and English Longitudinal Study of Ageing (ELSA) were used to examine associations between sense of purpose and allostatic load across 8 and 12 years of follow-up, respectively. Blood-based and anthropometric biomarkers were collected at four-year intervals and used to compute allostatic load scores based on clinical cut-off values representing low, moderate, and high risk. RESULTS: Population-weighted multilevel models revealed that sense of purpose in life was associated with lower overall levels of allostatic load in HRS, but not in ELSA after adjusting for relevant covariates. Sense of purpose in life did not predict rate of change in allostatic load in either sample. CONCLUSIONS: The present investigation supports sense of purpose predicting preserved differentiation of allostatic regulation, with more purposeful individuals demonstrating consistently lower allostatic load over time. Persistent differences in allostatic burden may account for divergent health trajectories between individuals low and high in sense of purpose.