The prevalence of cognitive impairment and disability associated with head injury in Scottish prisoners

Introduction: Head injury (HI) is associated with impairments in cognition, behaviour, emotion and lasting disability. HI in offender populations is higher than in the general population however studies do not report prevalence of disability. This study estimates the occurrence of disability, cognitive impairment, anxiety and depression in prisoners, and the numbers who may require assessment or intervention. Methods: A cross-sectional, between subjects design comparing severity of disability in 81 male prisoners with HI. Severity of HI was screened and outcome measures administered including the Glasgow Outcome at Discharge Scale (GODs), the Hospital Anxiety and Depression scale (HADs) and neuropsychological tests. Participants were grouped by duration of loss of consciousness (LoC) of greater (moderate-severe) or less (mild) than 30 minutes, and by number of HI’s. Results: Overall, between 31.3-56% of prisoners with moderate to severe HI are likely to require assessment and possibly intervention. HI was mild in n=65 and moderate-severe in n=16. Symbol Digit Modalities, clinical anxiety, and disability by HI were associated with duration of LoC after adjusting for covariates. Conclusions: Cognitive impairment, disability and clinical anxiety are more common in prisoners with moderate to severe HI with 31.3-56% likely to require follow up. Findings are preliminary and further large scale research is required