Sleep Insufficiency, Circadian Rhythms, and Metabolomics: The Connection to Metabolic and Sleep Disorders

Purpose

The majority of US adults who report experiencing insufficient sleep are more likely to suffer from metabolic disorders such as hyperlipidemia, diabetes, and obesity than those with sufficient sleep. Less is understood about the underlying molecular mechanisms connecting these phenomena. A systematic, qualitative review of metabolomics studies exploring metabolic changes in response to sleep insufficiency, sleep deprivation, or circadian disruption was conducted in accordance with PRISMA guidelines.

Methods

An electronic literature review in the PubMed database was performed considering publications through May 2021 and screening and eligibility criteria were applied to articles retrieved. The following keywords were used: "metabolomics” and "sleep disorders” or "sleep deprivation” or "sleep disturbance” or "circadian rhythm.” After screening and addition of studies included from reference lists of retrieved studies, 16 records were identified for review.

Results

Consistent changes in metabolites were observed across studies between individuals experiencing sleep deprivation as compared to non-sleep deprivation controls. Significant increases in phosphatidylcholines, acylcarnitines, sphingolipids, and other lipids are consistent across studies. Increased levels of amino acids such as tryptophan and phenylalanine are also noted. However, studies are limited to small samples of young, healthy, mostly male participants conducted in short inpatient sessions, limiting generalizability.

Conclusion

Changes in lipid and amino acid metabolites accompanying sleep deprivation and/or circadian rhythms may indicate cellular membrane and protein breakdown underlying the connection between sleep disturbance, hyperlipidemia, and other metabolic disorders. Larger epidemiological studies examining changes in the human metabolome in response to chronic insufficient sleep would help elucidate this relationship.