Recovery from sleep disturbance precedes that of depression and anxiety following mild traumatic brain injury: a 6-week follow-up study

OBJECTIVES: The detailed course of mental disorders at the acute and subacute stages of mild traumatic brain injury (mTBI), especially with regard to recovery from sleep disturbances, has not been well characterised. The aim of this study was to determine the course of depression, anxiety and sleep disturbance, following an mTBI. SETTING: We recruited patients with mTBI from three university hospitals in Taipei and healthy participants as control group for this study. PARTICIPANTS: 100 patients with mTBI (35 men) who were older than 20 years, with a Glasgow Coma Scale score of 13–15 and loss of consciousness for <30 min, completed the baseline and 6-week follow-up assessments. 137 controls (47 men) without TBI were recruited in the study. None of the participants had a history of cerebrovascular disease, mental retardation, previous TBI, epilepsy or severe systemic medical illness. PRIMARY OUTCOME MEASURES: The Beck Anxiety Inventory (BAI), the Beck Depression Inventory II (BDI), the Epworth Sleepiness Scale (ESS) and the Pittsburgh Sleep Quality Index (PSQI) were assessed for the patients with mTBI at baseline and 6 weeks after mTBI and for the controls. RESULTS: The ESS scores were not significantly different between the mTBI at baseline or at 6 weeks after mTBI and controls. Although the BAI, BDI and PSQI scores of the mTBI group were significantly different than those of the control group at baseline, all had improved significantly 6 weeks later. However, only the PSQI score improved to a level that was not significantly different from that of the control group. CONCLUSIONS: Daytime sleepiness is not affected by mTBI. However, mTBI causes depression and anxiety and diminished sleep quality. Although all these conditions improve significantly within 6 weeks post-mTBI, only sleep quality improves to a pre-mTBI level. Thus, recovery from mTBI-induced sleep disturbance occurs more rapidly than that of mTBI-induced depression and anxiety.