Does vulnerability to stress-related insomnia predict future incident and persistent insomnia among good sleepers?

• Published in: Sleep medicine Vol. 14; pp. e159 - e160
• Main Authors: Jarrin, D, Chen, I, Ivers, H, Morin, C
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.12.2013
• Subjects: Neurology; Sleep Medicine
• ISSN: 1389-9457; 1878-5506
• DOI: 10.1016/j.sleep.2013.11.368

Introduction Clinical and research evidence suggest that individuals who are more prone to experience situational insomnia under stressful conditions may also be at greater risk to eventually develop chronic insomnia. While there is substantial cross-sectional data on the association between heightened vulnerability to stress-related insomnia and sleep disturbances (i.e., low sleep efficiency, sleep fragmentation), there is limited data on its predictive value. The aim of the present study was to prospectively evaluate whether heightened vulnerability to stress-related insomnia was associated with increased risk of incident and persistent insomnia in a population-based sample of good sleepers. Materials and methods Data were derived from a larger epidemiological study conducted in Québec, Canada. Participants were 1449 adults (Mage = 47.4 yrs, SD = 15.1; 41.2% male) without insomnia at baseline and evaluated four times over 3-years. Vulnerability to stress-related insomnia was measured using the Ford Insomnia Response to Stress Test (FIRST). The Life Experience Survey was used to assess the frequency and perceived impact of positive and negative events that occurred in the past year. Incident insomnia was defined as a case reporting insomnia symptoms or syndrome at any of the follow-up evaluations (non-cumulative). Persistent insomnia was defined as a case reporting insomnia symptoms or syndrome at least twice during the follow-up evaluations. Results Of the sample, 91.7% completed the 6-month follow-up, 87.8% completed the 1-year follow-up, 84.1% completed the 2-year follow-up, and 71.5% completed the 3-year follow-up. After controlling for age, sex, depressive symptoms, and stressful events and perceived impact, individuals with a heightened vulnerability to stress-related insomnia had an odds ratio of 1.05 (95% CI: 1.03–1.07) of developing insomnia over a 3-year period and an odds ratio of 1.08 (95% CI: 1.05–1.11) of having persistent insomnia. When the FIRST was categorized into high and low scores (median score 20), odds ratio increased to 1.53 (95% CI: 1.23–1.91) and 2.11 (95% CI: 1.55–2.87) for incident and persistent insomnia, respectively. Conclusion Results suggest that heightened vulnerability to stress-related insomnia is associated with an increased risk of developing new onset and persistent insomnia in good sleepers. Knowledge of such premorbid differences is important to identify at-risk individuals, as this may help develop more targeted prevention and intervention strategies for insomnia. Acknowledgements This study was supported by the Canadian Institutes of Health Research ( MOP42504 ) and ( 127383 ).