Neuropsychiatric consequences of traumatic brain injury: A comparison between two age groups

Background: Neurobehavioural symptoms and certain psychiatric disorders are common after a traumatic brain injury ( TBI). Relatively few studies have investigated the effect of age upon these outcomes. Aim: Our aim was to compare the rates of neurobehavioural symptoms and psychiatric disorders between 18 - 65 year old and over 65 year old patients with TBI. Method: 120 adults aged 18 to 65 years and 45 adults over 65 years of age who were admitted to a hospital following a TBI were assessed for neurobehavioural symptoms and psychiatric disorders one year after the injury. Results: Our estimate suggested that a higher proportion of 18 - 65 year old patients ( 32%) had ICD- 10 psychiatric disorders according to the Schedule for Clinical Assessment in Neuropsychiatry ( SCAN) interview compared with patients over 65 years of age ( 16%). Similarly, the ICD- 10 depressive disorder was more common among the younger patients ( 16%) than the older group of patients ( 11%). None of these differences were statistically significant. However, a multiple regression analysis revealed that among other risk factors, a younger age was significantly associated with the presence of a psychiatric disorder. Also, a significantly higher rate of psychiatric caseness was detected among the younger age group using screening instruments such as the General Health Questionniare- 28 ( GHQ- 28) ( p < 0.01) and the Clinical Interview Schedule- Revised ( CIS- R) ( p < 0.01). The rates of individual neurobehavioural symptoms varied significantly between the two age groups. The most prevalent symptoms in 18 - 65 year olds were irritability ( 37%) and sleep problems ( 37%). In the older group of patients the most prevalent symptoms were poor memory ( 40%), dependence ( 38%) and slowness in thinking ( 33%). Conclusion: 18 - 65 year old patients are likely to be at a greater risk of psychiatric morbidity following TBI than over 65 year olds whereas neurobehavioural symptoms are prevalent in both age groups.