Association between insomnia symptoms and mortality: a prospective study of U.S. men

Insomnia complaints are common in older adults and may be associated with mortality risk. However, evidence regarding this association is mixed. Thus, we prospectively examined whether men with insomnia symptoms had an increased risk of mortality during 6 years of follow-up.

A prospective cohort study of 23,447 US men participating in the Health Professionals Follow-Up Study and free of cancer, reported on insomnia symptoms in 2004, were followed through 2010. Deaths were identified from state vital statistic records, the National Death Index, family reports, and the postal system. We documented 2025 deaths during 6 years of follow-up (2004-2010). The multivariable-adjusted hazard ratios of total mortality were 1.25 (95% confidence interval [CI], 1.04-1.50) for difficulty initiating sleep, 1.09 (95% CI, 0.97-1.24) for difficulty maintaining sleep, 1.04 (95% CI, 0.88-1.22) for early-morning awakenings, and 1.24 (95% CI, 1.05-1.46) for nonrestorative sleep, comparing men with those symptoms most of the time with men without those symptoms, after adjusting for age, lifestyle factors, and presence of common chronic conditions. Men with difficulty initiating sleep and nonrestorative sleep most of the time had a 55% (hazard ratio, 1.55; 95% CI, 1.19-2.04; P-trend=0.01) and 32% (hazard ratio, 1.32; 95% CI, 1.02-1.72; P-trend=0.002) increased risk of cardiovascular disease mortality, respectively, relative to men without those symptoms.

Some insomnia symptoms, especially difficulty initiating asleep and nonrestorative sleep, are associated with a modestly higher risk of mortality.