Abstract
OBJECTIVES: To test the hypotheses that decision making ability declines in old age and that a higher level of cognitive reserve is associated with a reduced rate of decline. METHODS: As part of an ongoing cohort study, 982 older adults without dementia at study enrollment completed measures of purpose in life and cognitive activity which were used as markers of cognitive reserve. At annual intervals thereafter, they completed 6 tests of decision making. RESULTS: In a factor analysis of baseline decision making scores, 3 measures (financial/health literacy, financial/health decision making, scam susceptibility) loaded on an "analytic" factor and 3 (temporal discounting small stakes, temporal discounting large stakes, risk aversion) loaded on a "preferences" (for temporal discounting and avoiding risk) factor. During a mean of 4.7 years of follow-up (standard deviation = 2.9), analytic factor scores decreased (mean = 0.042-unit per year, standard error [SE] = 0.006, p < .001) and preferences factor scores increased (mean = 0.021-unit per year, SE = 0.006, p < .001), with a correlation of 0.13 (p < .001) between rates of change. Evidence of an association between cognitive reserve and decision making was mixed with purpose in life related to change in analytic decision making, whereas past (but not current) cognitive activity was related to change in decision making preferences. DISCUSSION: Decision making analysis and preferences change over time in late life. Change over time in decision making components is relatively independent and differentially related to age and cognitive reserve.