Investigators in the Yale Department of Psychiatry demonstrated that females and males report differently regarding the family history of Alzheimer’s disease. In particular, the scientists observed that socioeconomic factors and cognitive abilities contribute to altering the assessment of the family history of Alzheimer’s disease in large-scale studies.

Alzheimer’s disease is one of the most challenging diseases of this century due to the increasing ageing population worldwide. Understanding the predisposition to this condition has become a priority in biomedical research to identify interventions to reduce the disease burden on individuals, families, and society. Many studies have used information regarding family history to identify individuals at high risk of developing Alzheimer’s disease.

Because of the known sex difference in the disease prevalence (women are two to three times more likely to develop Alzheimer’s than men across all age strata after the age of 65), Yale investigators analyzed clinical and genetic data from more than 650,000 participants enrolled in two national biobanks to assess how socioeconomic factors and cognitive abilities can influence recalling and reporting of family history of Alzheimer’s disease in females and males.

The findings were published in the journal Alzheimer’s and Dementia.

“Multiple forms of bias—including participation, information, and confounding biases—can mislead our understanding of factors related to Alzheimer’s disease. Targeted corrective strategies should be considered to mitigate their impact in both observational and genetic studies based on self-reported family history data,” said Jun He, PhD, postdoctoral fellow at Yale School of Medicine and first author of the study.

The study highlighted that socioeconomic factors and cognitive abilities may confound information regarding parental history of Alzheimer’s disease. Specifically, the findings could support several dynamics: limited access to medical services could lead to underestimates of Alzheimer’s diagnosis of parents; self-reported records could suffer more from recall bias in a population with cognitive decline; parents of individuals of lower socioeconomic status may die before developing Alzheimer’s. In this context, the differences observed between females and males may be related to the interplay between sexes, healthcare disparities, and life expectancy.

“Information regarding family history is often used to make clinical decisions and design research studies. Beyond Alzheimer’s disease, our findings highlight the importance of evaluating the potential confounders affecting family history assessment,” said Renato Polimanti, PhD, associate professor of psychiatry at Yale School of Medicine and senior author of the study.

The authors acknowledge support from the National Institutes of Health (R33 DA047527; RF1 MH132337, 5K99AG078503-02). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. Support also came from One Mind, the Alzheimer’s Association, the American Foundation for Suicide Prevention, the Yale Franke Program in Science and Humanities, the Yale Department of Psychiatry, and the Yale School of Medicine.