Development and internal validation of a nomogram for visualising multidimensional correlates of baseline suicide‑attempt history among hospitalized adolescents and young adults with mental disorders

Abstract

Suicide is prevalent among adolescents and young adults with mental disorders (AYAMD). Identifying factors associated with suicide‑attempt history and characterising risk profiles are essential for targeted suicide prevention in this high‑risk inpatient population. The study included 542 AYAMD who underwent in‑hospital treatment from October 2022 to December 2023. We collected information on patients’ clinical characteristics, Brøset Violence Checklist risk, and serum hormone levels. The patients were randomly divided into a training set ( n = 379) and a validation set ( n = 163) at a ratio of 7:3. Patient variables were analysed using LASSO regression, and the selected variables were further incorporated into a multivariate logistic regression model. A nomogram was constructed to visualise these multivariable correlates, and the discriminatory performance, calibration and clinical utility of the nomogram were assessed using the area under the receiver operating characteristic curve (AUC), calibration curves and decision curve analysis (DCA). Five variables were retained in the nomogram: non‑suicidal self‑injury (NSSI), prolactin, plasma total cortisol (PTC), number of hospitalizations and educational level. The AUC values of the training and validation sets were 0.771 (95% CI: 0.715 to 0.827) and 0.788 (95% CI: 0.711 to 0.865), respectively. The calibration curve revealed strong agreement between model‑derived probabilities and actual observed outcomes. The Hosmer‑Lemeshow test yielded χ² = 12.672 ( P = 0.123) for the training set and χ² = 8.919 ( P = 0.349) for the validation set, indicating satisfactory model fit. DCA identified effective thresholds ranging from 19% to 73% in the training set and 10% to 74% in the validation set, indicating favourable clinical utility for risk stratification reference. This cross‑sectional nomogram incorporating NSSI, prolactin, plasma total cortisol, educational level and number of hospitalizations achieves moderate discriminative capacity for characterising baseline suicide‑attempt history profiles among hospitalized AYAMD patients. It serves primarily as a quantitative tool for visualising risk correlates, rather than a standalone clinical screening instrument, and may act as an auxiliary quantitative reference to help clinicians identify high‑risk patient profiles and inform targeted suicide‑prevention interventions. This study was registered in Chinese Clinical Trial Registry (registration number: ChiCTR2300076195). Registration Date: 2023/09/27.