A retrospective analysis of concussion and post-concussional syndrome diagnoses in Western Australian emergency departments

Objective(s): To determine the rate of concussion diagnoses per capita recorded in hospital emergency departments in Western Australia (WA) from 2002-2018 for ICD-10-AM concussion diagnoses S06.00-S06.05, and post-concussional syndrome (PCS) (F07.2). Design, setting and analysis: Retrospective analysis of hospital Emergency Department (ED) presentations and hospital admissions from all WA hospitals for all patients with an ICD-10-AM diagnosis code for concussion and post-concussional syndrome (PCS) over the period 2002-2018. Data pertaining to concussion and PCS presentations were extracted from the WA Department of Health Emergency Department Data Collection (EDDC). Total case numbers were aggregated by year (2002-2018) and regions of WA. Main outcome measures: The rates of diagnoses were calculated based on the population in the specific region and expressed as incidence rate per 100,000 person-years. The overall trends of diagnoses across the regions were analysed using negative binomial regression models and expressed as incidence rate ratio (IRR) with the corresponding 95 % CI, whilst adjusting for region. Tests for linearity were also performed. Results: The rate of concussion diagnosis had significantly increased linearly over the years (p for trend: p < 0.001) whilst the rate of PCS diagnosis had significantly declined linearly over the same period (p for trend: p < 0.001). Conclusion: There was significant increase in all-cause ICD-10-AM concussion diagnoses in WA emergency departments. To further clarify the incidence and prevalence of all-cause concussion in Australia, investigation must focus on truly reflective S06.0 codes and include data linkage to primary care data. Conversely PCS ED presentations reduced; whether this relates to a change in where presentations occur for management of such a diagnosis, improved early intervention or an alternative explanation warrants further investigation.