Association between polygenic propensity for a psychiatric disorder and nutrient intake

Abstract

BackgroundDespite the observed associations between psychiatric disorders and nutrient intake, genetic studies are limited.AimsWe examined whether polygenic scores for psychiatric disorders, including anorexia nervosa, major depressive disorder and schizophrenia, are associated with self-reported nutrient intake.MethodsWe used data obtained by the UK Biobank ‘Diet by 24-hour recall’ questionnaire (N=163,619). Association was assessed using linear mixed models for the analysis of data with repeated measures.ResultsWe find polygenic scores for psychiatric disorders are differentially associated with nutrient intake, with attention-deficit/hyperactivity disorder, bipolar disorder and schizophrenia showing the strongest associations, whilst autism spectrum disorder showed no association. Expressed as the effect of a one standard deviation higher polygenic score, anorexia nervosa polygenic score was associated with higher intake of fibre (0.06 g), folate (0.93 μg), iron (0.03 mg) and vitamin C (0.92 μg). Similarly, a higher major depressive disorder polygenic score was associated with 0.04 mg lower iron and 1.13 μg lower vitamin C intake per day, and a greater obsessive-compulsive disorder polygenic score with 0.06 g higher fibre intake. These associations were predominantly driven by socioeconomic status and educational attainment. However, a higher alcohol dependence polygenic score was associated with higher alcohol intake and individuals with higher persistent thinness polygenic scores reported their food to weigh 8.61 g less, both independent of socioeconomic status.ConclusionsOur findings suggest that polygenic propensity for a psychiatric disorder is associated with dietary behaviour. The nutrient intake is based on self-reported data and findings must therefore be interpreted mindfully.Declaration of interestNone.