A new large-scale genetic study found that low body mass index (BMI) is likely not a causal risk factor for Alzheimer’s disease, as earlier research had suggested, according to a study published in the Journal of Clinical Endocrinology & Metabolism.
To examine the association between Alzheimer’s disease and low BMI, the researchers analyzed blood and DNA samples from 95,578 participants in the Copenhagen General Population Study (CGPS). Of the participants, 645 individuals developed Alzheimer’s disease.
The researchers analyzed the study participants’ DNA for the presence of five genetic variants that have strong associations with BMI. Based on how many variants were found, participants were divided into four groups to reflect the likelihood of low BMI. The researchers also analyzed data from up to 249,796 individuals participating in the Genetic Investigation of ANthropometric Traits (GIANT) consortium for the genetic variants closely linked to low BMI.
The analysis found the presence of the genetic variants tied to low BMI was not associated with increased risk of Alzheimer’s disease. For comparison, the researchers examined if individuals with genetic variants connected to high BMI were more likely to have type 2 diabetes and did find the expected causal relationship.
Paper: “Body Mass Index and Risk of Alzheimer Disease: a Mendelian Randomization Study of 399,536 Individuals”
Reprinted from materials provided by The Endocrine Society.