Longitudinal associations between time-varying insomnia symptoms and all-cause health care services utilization among middle-aged and older adults in the United States

Objective: To examine longitudinal associations between time-varying insomnia symptoms (difficulty initiating sleep, difficulty maintaining sleep, early-morning awakenings, and nonrestorative sleep) and all-cause health care services utilization (HSU), including overnight hospital stays, nursing home stays, and home health care services among middle-aged and older adults. Data Sources: The Health and Retirement Study (HRS), a nationwide, population-representative survey of primarily middle-aged and older adults in the United States. Study Design: This study is an analysis of prospective data from the HRS for a cohort of 13,168 adults (aged ≥50 years; females = 57.7%). Study participants were followed for 16 years. This study focuses on the associations between time-varying insomnia symptoms, both cumulatively and independently, and repeated HSUs. A marginal structural modeling approach was used to capture time-varying biological, psycho-cognitive, and behavioral health factors, and to adjust for selection bias such as differential loss to follow-up. Generalized estimating equations were employed to compute average marginal effects and their 95% confidence intervals. Data Collection/Extraction Methods: We extracted longitudinal data from 2002 through 2018 waves of the HRS. Principal Findings: Experiencing higher numbers of insomnia symptoms on a cumulative scale was associated with higher probabilities of HSU. For instance, the likelihood of overnight hospital stays for individuals reporting one symptom increased from 4.7 percentage points on average (95% CI: 3.7–5.6, p \u3c 0.001), to 13.9 percentage points (95% CI: 10.3–17.5, p \u3c 0.001) for those reporting four symptoms, relative to individuals experiencing no insomnia symptoms. Further, experiencing each of difficulty initiating and maintaining sleep, and nonrestorative sleep, as standalone symptoms, was associated with a higher likelihood of HSU when compared to those not experiencing the symptoms. Conclusions: The results demonstrate the potential consequences and adverse impacts of insomnia symptoms on HSU among middle-aged and older adults. Future investigations should focus on the underlying causes and health systems pathways linking insomnia symptoms to HSU