Burden of Insomnia Disorder Among US Active-Duty Military Personnel

BACKGROUND AND OBJECTIVES: Insomnia is highly prevalent among military personnel, with many gaps in knowledge. The purpose of this study was to quantify the medical, psychiatric, and utilization burden of insomnia among active-duty military personnel. We hypothesized that insomnia is associated with worsened health and economic outcomes. METHODS: This was a retrospective case-control study. Data were derived from the Military Data Repository (2016-2021). Active-duty service members (ADSMs) younger than 65 years, with 12 months of continuous enrollment before and after first insomnia diagnosis and no evidence of previous insomnia or insomnia treatment, were matched 1:1 on demographic, clinical, and military characteristics to ADSMs without insomnia. Insomnia and psychiatric and medical comorbidities were defined using International Classification of Diseases, 10th Revision diagnostic codes. The impact of newly diagnosed insomnia on psychiatric and medical outcomes within 12 months was examined using time-to-event models. The impact of newly diagnosed insomnia on 12-month health care resource utilization (HCRU) was examined using generalized linear models. RESULTS: A total of 40,978 ADSMs met insomnia criteria and were matched to 40,978 ADSMs without insomnia. Participants were 78.6% male and 61.8% identified as White, with most younger than 44 years (90.3%). Insomnia was associated with increased risk of almost every studied physical and psychological health outcomes; relative to those without insomnia, ADSMs with insomnia demonstrated a 6-fold increased risk of post-traumatic stress disorder (hazard ratio [HR] 6.51, 95% CI 5.95-7.12, p < 0.001), as well as elevated risk of traumatic brain injury (HR 5.32, 95% CI 4.53-6.24, p < 0.001). ADSMs with insomnia demonstrated greater all-cause HCRU across all points of service (all p's < 0.001). DISCUSSION: Among active-duty personnel, new-onset insomnia was associated with substantially increased risk of adverse medical and psychiatric burden, as well as increased utilization, over 12 months. Key limitations include our observational study design.