Association between perceived risk of Alzheimer's disease and related dementias and cognitive function among U.S. older adults

Introduction: The aim of the study was to assess factors associated with the perceived risk of developing Alzheimer's disease and related dementias (ADRD) and how the perceived risk of ADRD was related to cognitive function. Methods: We conducted a retrospective cohort study using 5 waves of data from the Health and Retirement Study (2012–2022) that included adults aged 65 years or older with no previous diagnosis of ADRD at baseline. Cognitive function was measured at baseline and over time using a summary score that included immediate/delayed word recall, serial 7′s test, objective naming test, backwards counting, recall of the current date, and naming the president/vice-president (range = 0–35). Perceived risk of developing ADRD was categorized at baseline as “definitely not” (0% probability), “unlikely” (1–49%), “uncertain” (50%), and “more than likely” (>50–100%). Additional baseline measures included participants’ sociodemographic background, psychosocial resources, health behaviors, physiological status, and healthcare utilization. Results: Of 1457 respondents (median age 74 [IQR = 69–80] and 59.8% women), individuals who perceived that they were “more than likely” to develop ADRD had more depressive symptoms and were more likely to be hospitalized in the past two years than individuals who indicated that it was “unlikely” they would develop ADRD. Alternatively, respondnets who perceived that they would "definitely not" develop ADRD were more likely to be non-Hispanic Black, less educated, and have lower income than individuals who indicated it was “unlikely” they would develop ADRD. Respondents who reported their risks of developing ADRD as “more than likely” (β = −2.10, P < 0.001) and “definitely not” (β = −1.50, P < 0.001) had the lowest levels of cognitive function; and the associations were explained in part by their socioeconomic, psychosocial, and health status. Conclusions: Perceived risk of developing ADRD is associated with cognitive function. The (dis)concordance between individuals’ perceived risk of ADRD and their cognitive function has important implications for increasing public awareness and developing interventions to prevent ADRD.