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

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.

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.

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.

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.