Increased risk of new-onset depression in patients with traumatic brain injury and hyperlipidemia: the important role of statin medications.

Abstract

Depression is a common complication after traumatic brain injury (TBI). This study aimed to evaluate the risk of hyperlipidemia for new-onset depression after TBI and the role of statin medications using a longitudinal population database. A matched longitudinal cohort study of 3,792 subjects (1,264 TBI patients [ICD-9-CM code: 801-804 and 850-854] with preexisting hyperlipidemia [ICD-9-CM code: 272.0, 272.1, 272.2, 272.4] and 2,528 age- and sex-matched TBI patients without hyperlipidemia) was conducted using the Taiwan Longitudinal Health Insurance Database from January 2001 to December 2008. The incidence and hazard ratios (HRs) for the development of new-onset depression (ICD-9-CM code: 296.2X-296.3X, 300.4, and 311.X) after TBI were compared between the 2 groups. The incidence rate of depression in TBI with preexisting hyperlipidemia was 136.61 per 10,000 person-years. TBI patients with preexisting hyperlipidemia had a 1.72-fold increased incidence rate ratio compared with those without hyperlipidemia (P = .0056). A Cox model showed hyperlipidemia to be an independent predictor of depression (HR = 1.61; 95% CI, 1.03-2.53). TBI patients with hyperlipidemia who were not treated with statins experienced a 1.95-fold incidence risk ratio (P = .0017) and higher risk of new-onset depression (HR = 1.61; 95% CI, 1.03-2.53) compared to TBI patients without hyperlipidemia. Preexisting hyperlipidemia could be an independent predictor of new-onset depression in TBI patients, and TBI patients with preexisting hyperlipidemia who were not treated with statins presented a higher risk of new-onset depression than TBI patients without hyperlipidemia. Our findings may provide some insight into the important role of statin medications in the development of new-onset depression in patients with traumatic brain injury.