Daily stress magnifies the association between cognitive decline and everyday memory problems: An integration of longitudinal and diary methods

We examined whether long-term fluid cognitive decline was associated with memory problems in everyday life, and whether stress plays a moderating role. We expected that the association between cognitive decline and everyday memory problems would be magnified in the context of self-reported and physiological stress. Data are from the Boston Longitudinal Study, a subsample of the Midlife in the United States study. Participants in the current study (n = 112) completed a battery of tests measuring fluid cognitive functioning at Time 1 (T1) and 2 (T2) over 10 years. At T2, participants completed weekly diaries of self-reported daily stressors and everyday memory problems for 12 consecutive weeks. Also at T2, participants provided 4 saliva samples over the course of 1 day to assess physiological stress using diurnal cortisol profiles [cortisol awakening response (CAR) and diurnal cortisol slope (DCS)]. Selfreported daily stressors and a less healthy DCS were associated with more everyday memory problems, and participants with greater cognitive decline reported more memory problems compared to those with less or no decline. Self-reported daily stressors and CAR moderated the relationship of cognitive decline and memory problems. As expected, more cognitive decline was associated with greater increases in memory problems on weeks when individuals reported more daily stressors and for individuals with a less healthy CAR. The current findings can inform interventions aimed to identify factors, such as daily stress, that contribute to daily functioning in the context of cognitive decline.