Associate Professor Graeme Hawthorne1
Professor Andrew Kaye 1,2
Professor Russell Gruen 3,4
Professor Jeffrey Rosenfeld 3,5
Professor Kathryn McPherson 6
Professor Robert Goldney 7
1University of Melbourne
2 Royal Melbourne Hospital
3 Monash University
4 National Trauma Research Institute
5The Alfred Hospital
6 Auckland University of Technology
7 University of Adelaide
Beyond Blue Victorian Centre of Excellence
Project completion year
The literature reports that between 23 to 45 per cent of people who are injured with a traumatic brain injury (TBI) will suffer from depression. One of the reasons for this variability is that different researchers use different instruments to assess depression; it is possible that, where older instruments are used, there may be misclassification and inflated rates of post-TBI depression. Additionally, there is little information on the depression recovery trajectory of people after a TBI. Some people may suffer acute or delayed depression. This study aimed to investigate these issues.
Depression-specific measures were administered within an existing study of long-term TBI outcomes.
Participants were recruited from two hospital sites in Melbourne (Australia), and were administered the standard QOLIBRI (Quality of Life after Brain Injury) questionnaire plus two different measures assessing depression (the recent World Health Organization Composite International Diagnostic Interview (CIDI) and the much older Hospital Anxiety and Depression Scale (HADS)), a measure of demoralization (Demoralization Scale (DS)) and psychological distress (K10). Data was collected at six-, 12- and 18-months post-TBI.
The participation rate was 63 per cent of all eligible TBI-patients, and 70 per cent of study participants completed 18-month follow-up questionnaires. The key finding was that depression prevalence varied by assessment method. At six months post-TBI, 34 per cent of participants were suffering a high level of psychological distress, 31 per cent were demoralized, 25 per cent suffered depression based on the HADS and 7 per cent suffered from depression using the CIDI.
These findings suggest that psychological stress and depression after TBI varies according to how it is assessed. The second key finding was that over the study period there was a slight decline in the percentage of participants suffering high psychological distress (from 34 per cent at six months to 32 per cent at 18 months). There was no change in demoralization (31 per cent at six months and 32 per cent at 18 months). The prevalence of depression on the CIDI marginally increased (7 per cent at six months and 8 per cent at 18 months), but marginally decreased on the HADS (25 per cent at six months to 23 per cent at 18 months). Very few cases experienced depression across the study period. Based on the CIDI, of the 31 cases who were depressed at any time, 15 cases were depressed at six months, but only four of these were still depressed at 18 months, whereas there was an additional 15 cases with depression at 18 months who had not been previously depressed.
These findings suggest that depression after TBI is not a given state, but varies at different time points in the recovery period and may increase over time. Regarding quality of life (QOL) after a TBI, average scores on the QOLIBRI improved between six and 18 months post-TBI, from 67 per cent to 70 per cent of the scale score, suggesting a very small improvement in QoL.
The differences between the two depression instruments (CIDI and HADS) suggest an urgent need to reconcile the different methods of assessing depression.
The other key outcome suggests that long-term follow-up of TBI patients should include regular screening for depression and, where symptoms are reported, patients should be referred for full mental health assessment.
Implications for policy and practice
This study concerned issues of measuring depression and depression trajectories over an 18-month period following a TBI. The key findings suggest that the use of older measures for the delineation of depression leads to over-classification. It is recommended that further studies are funded to investigate this phenomenon, with particular emphasis on the differentiation of psychological distress and depression. Provision should be made for monitoring those with TBI over an extended period.
Translation of the findings into practice
Clinicians and service providers should note that there are issues in the delineation of depression and that delineation should be based on a full mental health examination.
The use of older measures that may over-delineate depression should be discouraged.
Provision should be made for monitoring those with TBI over an extended period.
Whilst there are no direct benefits to consumers and carers, if clinicians start to use modern methods of depression assessment, resources may be directed at those with TBI who are most in need of care.