Long-term trajectories and current BMI are associated with poorer cognitive functioning in middle-aged adults at high Alzheimer's disease risk

Introduction: We examined relationships of body mass index (BMI) with cognition in middle-aged adults at Alzheimer's disease (AD) risk due to parental family history. Methods: Participants are offspring of AD patients from the Israel Registry of Alzheimer's Prevention (N = 271). Linear regressions assessed associations of BMI and cognition, and whether associations differed by maternal/paternal history. Analyses of covariance examined associations of long-term trajectories of BMI with cognition. Results: Higher BMI was associated with worse language (P = .045). Interactions of BMI with parental history were significant for episodic memory (P = .023), language (p = .027), working memory (P = .006), global cognition (P = .008); associations were stronger among participants with maternal history. Interactions of BMI trajectories with parental history were significant for episodic memory (P = .017), language (P = .013), working memory (P = .001), global cognition (P = .005), with stronger associations for maternal history. Discussion: Higher BMI and overweight/obese trajectories were associated with poorer cognition in adults with maternal history of AD, but not those with paternal history.