Prevalence and Predictors of Mechanical Restraint in Involuntary Patients in an Open-Door Inpatient Psychiatric Unit.

BACKGROUND: Mechanical restraint (MR) remains one of the most controversial interventions in psychiatry, particularly in involuntarily admitted patients. This study examined the prevalence and clinical predictors of MR in an open-door psychiatric unit in Spain, a context where national MR rates remain among the highest in Europe. METHODS: A retrospective descriptive study of all involuntarily admitted patients (n = 81) was conducted in a 20-bed open-door acute psychiatric unit between June and December 2024. Sociodemographic, diagnostic, and treatment variables were extracted from electronic health records. Bivariate analyses based on exact tests and Firth penalized-likelihood logistic regression were used to identify independent correlates of MR. RESULTS: MR was applied in 14.8% of patients. In Firth penalized-likelihood multivariable analysis, schizophrenia was the strongest independent correlate of MR (odds ratio [OR] = 9.58, 95% confidence interval [CI]: 1.71-65.89, p = 0.010). Male gender showed a significant bivariate association but lost significance after adjustment. MR co-occurred with intramuscular psychotropic medication in 91.7% of cases. CONCLUSIONS: Within this single-centre, exclusively involuntary cohort, care delivered in an open-door setting with structured de-escalation interventions was associated with a comparatively low rate of MR. Schizophrenia emerged as the strongest correlate of MR and may represent a priority target for prevention strategies. The results align with convergent evidence from German, Swiss, and Norwegian studies supporting the safety and effectiveness of open-door approaches, and provide the first Spanish data on MR in this model of care. These findings are preliminary and require confirmation in larger, multicentre samples.