Prevalence, natural course and predictors of depression 1 year following traumatic brain injury from a population-based study in New Zealand

Abstract

Objective: Depression is common post-TBI, yet has not been studied longitudinally, nor at a population level. This study examined prevalence of depression in a population-based sample across the first year post-TBI.

Design and methods: Prospective follow-up of 315 adults (>16 years) with assessments (Hospital Anxiety Depression Scale, DSM-IV criteria) at 1-, 6- and 12-months post-TBI. Demographic and injury-related predictors of depression at 1-year post-TBI were also explored.

Results: The number of individuals identified as depressed reduced significantly between baseline and 12-months post-TBI from 21–12.4% using the HADS and 49–34% using DSM-IV criteria; with only 10 of the 28 individuals initially meeting criteria on the HADS continuing to do so at 12-month follow-up. Meeting HADS depression criteria was linked to pre-morbid depression and/or anxiety; while those meeting DSM-IV criteria were older, but not significantly so.

Conclusions: The findings suggest depression is common post-TBI and that clinicians/researchers use caution in its diagnosis, as existing criteria have significant overlap with common TBI sequels.

• Depression
• population-based
• traumatic brain injury

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper. This study was funded by the New Zealand Health Research Council.