Longitudinal trends of the healthcare-seeking prevalence and incidence of insomnia in Taiwan: An 8-year nationally representative study

Objectives: We used insurance claims of a nationally representative population-based cohort to assess the longitudinal healthcare-seeking prevalence and incidence of insomnia. Methods: Participants were identified from National Health Insurance enrollees in Taiwan during 2002~2009. Individuals with insomnia were identified using ICD-9-CM diagnostic and procedure codes of 780.52, 307.41, and 307.42. Results: In 2009, the prevalence of insomnia was 5.4% for women and 3.0% for men; the incidence of insomnia was 1.6% for women and 1.3% for men. Patients who were female [odds ratio (OR)]=1.82, 95% confidence interval (CI)=1.79~1.86), older (50~64 years: OR=23.25, 95% CI=21.07~25.64; ≥65 years: OR=24.70, 95% CI=22.40~27.24), and in the middle-socioeconomic status group (OR=1.19, 95% CI=1.16~1.21) were more likely to have insomnia. An inverse U-shaped female/male ratio trend for the insomnia prevalence was found, and this ratio reached a peak around the menopausal transitional period. Conclusions: The persistence of healthcare-seeking behaviors with insomnia was more common in females. Our findings underscore the need to initiate treatment at an early stage as opposed to waiting for the spontaneous resolution of insomnia. Future research needs to identify causes of the persistence of insomnia and develop proper interventions to reduce its rising prevalence. More-active approaches toward preventive strategies for insomnia are needed, especially for women who are at higher risk of insomnia.