The relationship between insomnia and mortality among community-dwelling older women

Abstract

Objectives: To investigate the relationship between insomnia and 6-year survival among older, community-dwelling, white women.

Design: Longitudinal study.

Setting: The sample was selected randomly from a 20-census tract area of Baltimore, Maryland.

Participants: In 1984, 778 women aged 65 years and older participated in the baseline survey; 613 were re-interviewed in 1985; 596 were reinterviewed in 1986.

Measurements: Insomnia was measured as self-report of at least one of three sleep complaints: trouble initiating sleep, waking at night and trouble falling back to sleep, and waking too early. Cox proportional hazards models were used to assess the relationship between insomnia, as reported at the most recent of three interviews, and mortality.

Results: Twenty-nine percent of the sample reported trouble initiating sleep, 22.4% reported waking at night and having trouble falling back to sleep, and 26.6% reported waking too early. Of the sample, 43.2% had insomnia at the baseline interview; 23.2% percent of respondents with insomnia at baseline died during the follow-up period compared with 22.0% of those without insomnia at baseline. Recent insomnia was not associated significantly with mortality in either crude analyses (Hazards Ratio (HR) = 1.11, 95% CI, 0.78-1.60) or analyses adjusted for age, prescription medication use, functional limitations, self-rated health, and number of chronic conditions (HR = 0.74, 95% CI, 0.50-1.09).

Conclusion: Our results, combined with the results from previous studies, suggest strongly that insomnia is not an indicator of approaching mortality in older community-dwelling populations.