Disruption of circadian rhythms promotes alcohol use: a systematic review

Abstract

This systematic review investigates the bidirectional relationship between alcohol consumption and disrupted circadian rhythms. The goal of this study was to identify (i) the types of circadian rhythm disruptors (i.e. social jet lag, extreme chronotypes, and night shift work) associated with altered alcohol use and (ii) whether sex differences in the consequences of circadian disruption exist. We conducted a search of PubMed, Embase, and PsycINFO exclusively on human research. We identified 177 articles that met the inclusion criteria. Our analyses revealed that social jet lag and the extreme chronotype referred to as eveningness were consistently associated with increased alcohol consumption. Relationships between night shift work and alcohol consumption were variable; half of articles reported no effect of night shift work on alcohol consumption. Both sexes were included as participants in the majority of the chronotype and social jet lag papers, with no sex difference apparent in alcohol consumption. The night shift research, however, contained fewer studies that included both sexes. Not all forms of circadian disruption are associated with comparable patterns of alcohol use. The most at-risk individuals for increased alcohol consumption are those with social jet lag or those of an eveningness chronotype. Direct testing of the associations in this review should be conducted to evaluate the relationships among circadian disruption, alcohol intake, and sex differences to provide insight into temporal risk factors associated with development of alcohol use disorder.

Keywords: alcohol; alcohol use disorder (AUD); chronotype; circadian disruption; circadian rhythm; eveningness; morningness; social jet lag.

Figure 1

PRISMA flow chart of study design

Figure 2

Social jet lag, chronotype, shift work studies and distribution of male and female participants. (A) Social jet lag and chronotypes: there was high concurrence that these factors increase alcohol use (n = 66). (B) Night shift: there are disparate alcohol use outcomes depending on whether all papers are grouped together (a) versus grouped by the sex or sexes of the participants. The difference in the outcome patterns among papers that include both sexes (b; n = 45), females only (c; n = 22), or males only (c; n = 33) highlights potential differences between men and women in the effects of night shift work on alcohol use. Furthermore, 9% (4 of 45) of the papers that included both sexes reported a significant effect in women but not men (referred to as “split outcomes”). One paper did disclose the sexes of the participants. (C) Male and females: (a) >80% of social jet lag and chronotype papers included both males and females. (b) In contrast, the night shift studies are skewed toward males and ~44% of the studies include participants of both sexes