Purpose in life and cognitive health: a 28-year prospective study.

OBJECTIVES: To examine the prospective association between purpose in life measured at three points across middle and older adulthood and cognitive outcomes assessed 8-28 years later.

DESIGN: Prospective Study.

SETTING: Wisconsin Longitudinal Study of Aging (WLS).

PARTICIPANTS: WLS participants who reported on their purpose in life at Round 4 (1992-1994; M age = 52.58), Round 5 (2003-2007; M age = 63.74), and/or Round 6 (2010-2012; M age = 70.25) and were administered a cognitive battery at Round 7 (2020; M age = 79.94) were included in the analysis ( N = 4,632).

MEASUREMENTS: Participants completed the Ryff measure of purpose in life and were administered the telephone interview for cognitive status and measures of verbal fluency, digit ordering, and numeric reasoning.

RESULTS: Purpose in life measured at age 52 was related to better global cognitive function and verbal fluency but unrelated to dementia at age 80. In contrast, purpose in life at ages 63-70 was associated with lower likelihood of dementia, as well as better global cognitive function and verbal fluency at age 80. The effect sizes were modest (median Beta coefficient = .05; median odds ratio = .85). A slightly steeper decline in purpose in life between ages 52 and 70 was found for individuals with dementia at age 80.

CONCLUSIONS: Purpose in life is associated with healthier cognitive function measured up to 28 years later. Individuals with lower purpose, especially in their 60s or older, and with steeper declines in purpose, are more likely to have dementia at age 80.