Approved Research

Insomnia with short sleep duration and its association with cardiometabolic diseases and life expectancy: evidence from the UK Biobank cohort.

Lay summary

Insomnia is a disorder defined by difficulties falling and/or staying asleep that result in impaired function. Over 33% of adults experience occasional symptoms, and 10-22% have chronic insomnia. Although its significance is often minimized, chronic insomnia has important health consequences including fatigue, depression and increased suicide risk, increased risk of cardiometabolic morbidity and mortality and   impaired social/vocational functioning and reduced quality of life. Moreover, insomnia contributes to increased health care utilization and costs, totaling over $285M for prescription sleeping pills and $90B in total direct treatment-related costs annually in the US. Furthermore, although recent systematic reviews and clinical practice guidelines support the efficacy of cognitive-behavioral treatment for insomnia (CBT-I) and various hypnotic medications, the general efficacy of available insomnia treatments is tempered by the fact that we know very little about which treatment works best for which patient. Identifying insomnia phenotypes that differ consistently on biological characteristics and treatment responses would help to maximize CBT-I treatment resources and minimize exposure to adverse medication effects. Since 2001, there has been consistent evidence that insomnia with short sleep duration (ISSD) is a more severe distinct phenotype associated with distinct pathophysiology i.e., activation of the stress system, increased health risks i.e., cardiometabolic diseases, neurocognitive impairment, depression and mortality and possibly differential treatment response. However, these previous studies were based on polysomnography, which may not reflect subjects' habitual sleep duration. In addition, there is paucity of research evaluating the association between insomnia and life expectancy. The proposed study will use ecological friendly methods i.e., home actigraphy, to  confirm and expand previous findings in large patient registries, and will explore the genetic underpinnings of this clinically important phenotype.

The primary aim of this study is to investigate the longitudinal independent association of the ISSD phenotype, based on subjective complaints and home actigraphy, with life expectancy and number of years lived with and without cardiometabolic diseases in men and women, using individual-level data from the UK Biobank. Further, our secondary aim is to explore whether the ISSD phenotype clusters in families and is associated with genetic polymorphisms, despite different degrees of shared environment. These findings based on clinically meaningful phenotyping of insomnia would aid the goals of precision medicine, in terms of prevention of adverse health impact and development of treatments based on clinical phenotypes and physiology as well as genetics