Alcohol use predicts emergency psychiatric unit admission for non-fatal suicidal behaviour in the Western Cape (South Africa): a case-control study.

Objective: We aimed to describe patterns of substance use among patients admitted to an emergency psychiatric unit for non-fatal suicidal behaviour (NFSB) or another psychiatric reason and establish whether there were significant differences in patterns of substance use between the two groups.Methods: We employed a case-control design (N = 50) and collected data about participants' substance use in Cape Town, South Africa. Data were analysed using Chi-square and Mann-Whitney tests, factor analysis, and logistic regressions.Results: Prevalence of lifetime Alcohol Use Disorder (AUD) was 60% in the NFSB group and 28% in the control group. 12% of the NFSB group and 20% of the control group had a lifetime Tobacco Use Disorder. Prevalence of lifetime illicit Substance Use Disorder was 44% in the NFSB group and 60% in the control group. Hospital admission for NFSB was associated with: any past 24-hour alcohol use; quantity of past 24-hour alcohol use; quantity of past-month alcohol use; lifetime AUD; past 12-month AUD; and current AUD; and was not associated with the use of any other substances (p<.05). Past 12-month AUD was the best predictor of hospital admission for NFSB, controlling for, respectively, any past 24-hour alcohol use (aOR = 13.33, p = .023) and quantity of past 24-hour alcohol use (aOR = 9.01, p = .022)Conclusions: Patients admitted to emergency psychiatric units for NFSB have increased needs for the treatment of AUDs compared to patients admitted for another psychiatric emergency. Findings support calls for interventions to prevent NFSB among psychiatric patients with a history of AUD.Key pointsRates of substance use among patients admitted to emergency psychiatric units in South Africa were high compared to the general population.Hazardous alcohol use was uniquely associated with hospital admission for non-fatal suicidal behaviour compared to another psychiatric emergency.Tobacco use and illicit substance use were not associated with hospital admission for non-fatal suicidal behaviour compared to another psychiatric emergency.The association between hazardous alcohol use and hospital admission for non-fatal suicidal behaviour did not appear to be affected by demographic variables.Patients admitted to hospital for non-fatal suicidal behaviour have increased needs for the treatment of alcohol use disorders compared to other psychiatric patients.