Outpatient Prescriptions for Insomnia Medications During the First Year Following Combat-Related Amputations

Sleep-related disorders are associated with pain, fatigue, and deficits in cognitive performance, which may interfere with successful rehabilitation. The study objectives were to (1) quantify outpatient prescriptions for insomnia medications during the first year following combat-related amputations, (2) examine longitudinal changes in prescriptions for insomnia medications, and (3) analyze patient characteristics associated with prescriptions for insomnia medications.

This was a retrospective study of DoD casualty records from the Expeditionary Medical Encounter Dataset and prescriptions for outpatient medications from the Pharmacy Data Transaction Service. Patients were a total of 1,651 U.S. service members who sustained major limb amputations in Operations Iraqi and Enduring Freedom from 2001 through 2017 and had outpatient prescriptions for any medication during the first year postinjury. Prescriptions for medications recommended for insomnia were low-dose antidepressants, anxiolytic sedatives, benzodiazepines, melatonin receptor agonist, and low-dose quetiapine. These prescription medications were analyzed by medication type, postinjury time, and patient characteristics during the first year postinjury.

During the first year postinjury, 78% of patients (1,291 of 1,651) had outpatient prescriptions for insomnia medications, primarily anxiolytic sedative drugs (e.g., zolpidem), averaging a total of 86 prescription days (median = 66). The prevalence of these prescriptions declined substantially during the first year, from 57% of patients during the first quarter to 28% during the fourth quarter postinjury. In univariate analyses, multiple patient characteristics, including high Injury Severity Score, continued opioid and non-opioid analgesic prescriptions, and diagnoses of chronic pain, mood disorder, and posttraumatic stress disorder, were significantly associated with higher prevalence and duration of outpatient prescriptions for insomnia medications.

The present results indicate a high prevalence of outpatient prescriptions for insomnia medications following combat-related amputations, a prevalence that is substantially higher than previously reported among active duty personnel. These findings can inform DVA/DoD guidelines for amputation care and insomnia among military subpopulations. The results highlight the need for more research on the treatment of insomnia during early postinjury rehabilitation among patients who sustained serious combat injuries.