Predictors of severe or multiple subsequent injuries over 24 months among an already-injured cohort in New Zealand

Abstract

IntroductionInterventions to reduce subsequent injuries among already-injured people presenting to healthcare providers may reduce the overall burden of injury. However, in order to develop such interventions it is necessary to understand what predicts subsequent injuries. This knowledge is currently limited for general injury populations. This prospective Subsequent Injury Study aims to determine pre-injury sociodemographic and heath factors, and injury-related factors, that predict subsequent injury claims reported to Accident Compensation Corporation (ACC, New Zealand's universal injury insurer) in the 24 months following an ACC entitlement claim injury (‘sentinel’ injury). Two separate outcome variables were used to identify subsequent injuries of interest: having (1) at least one high severity injury claim (New Injury Severity Scores ≥4), or (2) two or more claims (injuries of any severity). MethodsThis study combines: (1) participant interviews (from our earlier Prospective Outcomes of Injury Study), (2) ACC data about sentinel injuries which led to participants being recruited, and all subsequent injuries involving an ACC claim in the 24 months following that sentinel injury, and (3) hospital discharge data for sentinel and subsequent injuries involving hospitalisation. Potential predictors (pre-sentinel injury sociodemographic and health variables, sentinel injury related variables) were identified using modified Poisson regression models. ResultsSevere and multiple ACC-reported subsequent injuries (ACC-SI) were each more likely to occur for participants with a self-reported prior injury affecting them at the time of their sentinel injury, and for those who prior to their sentinel injury event had pain/discomfort, or were physically active on five or more days of the week. A lower likelihood of severe or multiple ACC-SI was more common in those aged 30–64 years compared with those aged 18–29 years, those of ‘other’ ethnicity compared to sole New Zealand European ethnicity, and if the sentinel injury involved hospitalisation. Multiple ACC-SI were more likely for males, and for participants with ≥2 chronic conditions compared to those with none. ConclusionsFactors identified in this study may provide useful flags to help healthcare providers and policy makers identify people at increased risk of severe or multiple subsequent injuries who may benefit from targeted injury prevention strategies or interventions.