# Insomnia

Insomnia is a sleep disorder: persistent trouble falling asleep, staying asleep, or getting restful sleep, despite having enough time to sleep, and it causes real daytime problems. By the DSM-5 and ICSD-3 definitions, chronic insomnia means symptoms at least 3 nights a week for at least 3 months. About 10% of adults meet the criteria, and it gets more common with age, making it one of the top sleep complaints in older people. At its core is 'hyperarousal'. Your stress system (the HPA axis and sympathetic nervous system) stays switched on, raising nighttime cortisol, body temperature, and brain glucose use, all of which fight sleep. The long-term stakes look real. A 2019 meta-analysis (Ge et al.), pooling 29 cohorts and over 1.5 million people, found that trouble falling asleep and non-restorative sleep independently raised death and heart-disease risk. (Insomnia as a formal diagnosis, and trouble staying asleep, did not reach significance.) The first-line treatment is CBT-I (cognitive behavioral therapy for insomnia), combining sleep restriction, stimulus control, cognitive work, and sleep hygiene, per the 2016 American College of Physicians guideline. Sleeping pills are add-on only, and riskier in older people.

## Sources

- Ge L, Guyatt G, Tian J, et al.. (2019). Insomnia and risk of mortality from all-cause, cardiovascular disease, and cancer: Systematic review and meta-analysis of prospective cohort studies. Sleep Medicine Reviews. https://doi.org/10.1016/j.smrv.2019.101215
- Qaseem A, Kansagara D, Forciea MA, et al.. (2016). Management of Chronic Insomnia Disorder in Adults: A Clinical Practice Guideline From the American College of Physicians. Annals of Internal Medicine. https://doi.org/10.7326/M15-2175
- Parthasarathy S, Vasquez MM, Halonen M, et al.. (2015). Persistent Insomnia is Associated with Mortality Risk. The American Journal of Medicine. https://doi.org/10.1016/j.amjmed.2014.10.015

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_Canonical: https://longevity-switzerland.com/en/glossary/insomnia · Part of Longevity Cities · Updated 2026-06-22_