Social jetlag in health and behavioral research : a systematic review

Abstract

Background: Even though light is considered the main cue that entrains inner biological rhythms according to circadian environmental rhythms, social organizations have the capacity to take the body “out of sync”. An emergent field of research on the topic refers to what has been described as social jetlag, the biological misalignment that arises from alternated work and free days. However, to the present moment, there is still controversial evidence on the effects of such a phenomenon to human health. Objective: The aim of this study was to identify current peer-reviewed evidence of the health and behavioral risks associated with social jetlag. Method: We conducted a systematic review of the literature on PubMed, Scopus, Embase and LILACS electronic databases using the terms “social AND (jet lag OR jetlag)”. The search was finalized on August 22, 2016, resulting in 26 research articles included in the review. Results and discussion: Our results point to a variety of health and behavioral outcomes that seem to be associated with the mismatch existent between work or study days and free days. They are epilepsy, minor psychiatric symptoms, aggression and conduct problems, mood disorders, cognitive impairment (eg, work and academic performance), substance use, cardiometabolic risk and adverse endocrine profiles. However, these results must be analyzed with caution because of the high methodological heterogeneity, the significant risk of bias of analyzed studies, as well as the low similarity among the populations described.