Use of Sleep Medications and Mortality: The Hordaland Health Study

BACKGROUND: Previous research suggests a possible link between the use of sleep medications and mortality, but findings are mixed and well-controlled community-based studies are lacking. OBJECTIVE: The aim of the current study was to examine the prospective association between sleep medications and all-cause mortality. METHOD: Using a cohort design with 13–15 years of follow-up, we linked self-reported medication use and data on possible confounders from the Hordaland Health Study (HUSK N = 21,826) obtained over the period 1997–1999 to mortality data from the Norwegian Cause of Death Registry. Users of sleep medications (n = 159) were defined as those reporting intake of any prescribed sleep medication (coded according to the Anatomical Therapeutic Chemical [ATC] classification system) on the day before participation in HUSK. Users of sleep medications were also asked if their intake was on a daily or a non-daily basis. Analyses presented are adjusted for sociodemographic and lifestyle factors, mental and physical health, and other medication use. RESULTS: We found that both type and frequency of sleep medication use were associated with increased general mortality risk. Compared with participants not using sleep medications, those who reported any use had a twofold risk for mortality (95 % confidence interval [CI] 1.1–3.7); the hazard ratio (HR) was 2.9 (95 % CI 1.4–5.9) for daily and 1.1 (95 % CI 0.3–3.4) for non-daily users. Mortality risk was higher for benzodiazepines (HR 3.1; 95 % CI 1.3–7.6), but not significant for short-acting benzodiazepine agonists (HR 1.5; 95 % CI 0.7–3.5). CONCLUSION: Community dwellers who use sleep medications, particularly benzodiazepines, had a significantly increased risk of dying during the 13–15 years of follow-up. The low numbers of individuals reporting chronic usage indicate that the data should be interpreted with great caution, and more well-controlled studies with registry-based information on sleep medication use are needed to further examine the potential harmful effects of sleep medications.