Sleep, somatic diseases and mortality

Authors

• Christer Hublin

DOI:

https://doi.org/10.23990/sa.4492

Abstract

Nearly half a century ago, the first report on the association between sleep length and subsequent mortality indicated a U-shaped curve showing that those sleeping 7 hours had the lowest mortality. The U-shaped association has been found in most of the later published epidemiologic studies and it has also been shown in two recently published meta-analyses. While the excess risk has been rather robust to adjustment for life-style and other factors, its precise nature still has remained obscure. Especially during the last decade studies have been published on the association between sleep length, obesity, and somatic diseases or disorders such as type II diabetes, cardio-vascular disease, and cancer. There is best evidence for associations between sleep length (U-shaped) and also sleep quality and type 2 diabetes, and short sleep and obesity in younger people. This review summarizes latest results and discusses limitations of present studies and knowledge (especially regarding causality and possible mechanisms) and also lists future challenges.