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Repeat Self-Inflicted Injury Among U.S. Youth in a Large Medical Claims Database
Cora Peterson1, Likang Xu1, Ruth W Leemis1
1National Center for Injury Prevention and Control, Centers for Disease Control and Prevention, Atlanta, Georgia.
Introduction:
This study describes characteristics of nonfatal self-inflicted injuries and incidence of repeat self-inflicted injuries among a large convenience sample of youth (aged 10-24 years) with Medicaid or commercial insurance.
Methods:
In 2018, Truven Health MarketScan medical claims data were used to identify youth with a self-inflicted injury in 2013 (or index self-inflicted injury) diagnosed in any inpatient or outpatient setting. Patients with 2 years of healthcare claims data (1 year before/after index self-inflicted injury) were assessed. Patient and injury characteristics, repeat self-inflicted injuries ≤1 year, time to repeat self-inflicted injury, and number of emergency department and urgent care facility visits per patient are reported. A regression model assessed factors associated with repeat self-inflicted injuries.
Results:
Among 4,681 self-inflicted injury patients, 70% were female. More than 71% of patients were treated for comorbidities (50% for depression) ≤1 year preceding the index self-inflicted injury. Poisoning was the most common index self-inflicted injury mechanism (60% of patients). Approximately 52% of patients had one or more emergency department visit and 1% had one or more urgent care facility visit, respectively, during the 2-year observation period. More than 11% of patients repeated self-inflicted injury ≤1 year (and 3% ≤7 days). Repeat self-inflicted injury was associated with younger patient age, being female, a self-inflicted injury event preceding the index self-inflicted injury, index self-inflicted injury treatment setting, and patient comorbidities.
Conclusions:
Approximately one in ten youth repeated self-inflicted injury within 1 year and nearly half of youth with clinically treated self-inflicted injuries never received care in hospitals or emergency departments. Physicians and families should be aware of risk factors for repeat self-inflicted injury, including mental health comorbidities. Multilevel strategies are needed to prevent youth self-inflicted injuries.
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