Sleep, Diet, and Cardiometabolic Health Investigations: a Systematic Review of Analytic Strategies

Abstract

Purpose of review: Poor sleep is a risk factor for cardiometabolic morbidity. The relationship of sleep and cardiometabolic health could be confounded, mediated, or modified by diet, yet the incorporation of diet in sleep-cardiometabolic health studies is inconsistent. This rapid systematic literature review evaluates the conceptualization of diet as a confounder, mediator, or effect modifier within sleep-cardiometabolic health investigations, and the statistical approaches utilized.

Recent findings: Of 4692 studies identified, 60 were retained (28 adult, 32 pediatric). Most studies included diet patterns, quality, or energy intake as confounders, while a few examined these dietary variables as mediators or effect modifiers. There was some evidence, mostly in pediatric studies, that inclusion of diet altered sleep-cardiometabolic health associations. Diet plays a diverse role within sleep-cardiometabolic health associations. Investigators should carefully consider the conceptualization of diet variables in these relationships and utilize contemporary statistical approaches when applicable.

Keywords: Body mass index; Cardiometabolic health; Confounding; Diet; Dietary quality; Effect modification; Mediation; Nutrition; Obesity; Sleep; Sleep duration; Sleep quality; Total energy intake.

Figure 1.

Causal diagram illustrating the different roles of diet on the sleep-cardiometabolic health pathway

Figure 2.

Selection of studies