Cognitive Functioning and Stress Response among Young Adults with and without a Family History of Alzheimer’s Disease
Alzheimer’s disease (AD) is the most common cause and commonly diagnosed form of dementia, and it remains the sixth leading cause of death in the United States. Age is the best predictor of AD, however, a family history of AD (+FH) is an established risk factor and reliable predictor of developing the disease. Individuals with a +FH have a higher incidence of being apolipoprotein ε4 (APOE ε4) allele carriers compared to those with no family history of AD (-FH). Those who face increased genetic vulnerability exhibit increased stress response and cognitive, structural, and functional brain differences even among childhood and young adult populations. However, little research has investigated the effects of acute physical stress on cognitive abilities among a younger, at-risk +FH population. This study aimed to elucidate the influence of physiological stress on cognitive functioning among +FH and -FH young adults. One hundred eleven young adults (n = 52 +FH; n = 59 -FH) were assessed for baseline heart rate (beats per minute) and salivary cortisol concentrations, followed by a baseline neuropsychological battery. Participants completed the cold pressor task (CPT) to induce physiological stress, for the comparison of stress response (salivary cortisol, HR BPM) between FH groups. Subsequently, participants underwent a recovery heart rate recording, completed a parallel form neuropsychological battery, and provided a post-CPT salivary cortisol sample. Results showed no significant interaction of FH status and stress condition on stress response nor cognitive test performance. However, +FH had higher verbal learning and delayed recall performance, but made more repetition errors than the -FH group. The present study’s findings have implications for future work and early interventions that may promote healthy cognitive aging and impede AD development.