Which predicts longevity better: Satisfaction with life or purpose in life?

Area of Science:

• Psychology
• Gerontology
• Public Health

Background:

• Life satisfaction and purpose in life are distinct but crucial for evaluating life quality and longevity.
• Both subjective well-being factors positively influence health and lifespan.
• The comparative predictive power of life satisfaction versus purpose in life on mortality remains unclear.

Purpose of the Study:

• To determine whether purpose in life or life satisfaction is a stronger predictor of mortality.
• To investigate the independent and combined effects of these well-being dimensions on longevity.
• To test the hypothesis that purpose in life may be a more direct predictor of mortality.

Main Methods:

• Utilized data from the Midlife in the U.S. survey, a 23-year longitudinal study with 5,993 participants.
• Employed Cox proportional hazards models to analyze mortality prediction.
• Performed analyses both with and without demographic and health-related covariates.

Main Results:

• Individually, both life satisfaction and purpose in life predicted mortality.
• When analyzed simultaneously with self-rated health, purpose in life remained a significant predictor of mortality.
• Life satisfaction's predictive power became marginally significant in the simultaneous model, suggesting overlap with other factors.

Conclusions:

• Purpose in life is a robust predictor of mortality and a vital component of healthy aging.
• The predictive association of life satisfaction with mortality is influenced by covariates and potentially explained by purpose in life and health.
• Focusing on purpose in life may be particularly important for promoting longevity and well-being in older adults.