Patient- and Ward-Level Determinants of Psychosomatic-Psychiatric Consultations for Mentally Distressed Inpatients from Medical Hospitals: Findings from the SomPsyNet Stepped-Wedge-Trial

ABSTRACT Background Up to one-third of medical inpatients experience clinically relevant mental distress, yet many remain untreated. Stepped and collaborative care (SCC) models may improve access to mental health care, but predictors of service uptake are unclear. We examined patient- and ward-level predictors of psychosomatic-psychiatric consultation (PPC). Methods We analyzed data from SomPsyNet, a stepped-wedge cluster randomized trial targeting SOMatic inpatients across three Swiss tertiary hospitals, to prevent PSYchosocial distress by a care NETwork. Analyses focused on inpatients screening positive for mental distress. Multiple-imputed logistic regressions assessed predictors of four sequential service-use stages: PPC considered, offered, accepted, and received. Results Among 589 distressed patients, 93.9% were offered PPC, 63.1% accepted, and 83.9% of acceptors received PPC, yielding a 50% overall receipt rate. Patients without Swiss citizenship showed higher odds of acceptance (odds ratio [OR]=1.82 [1.10, 3.00]) and eventual receipt (OR=1.62 [1.01, 2.62]). Being in a Geriatric ward facilitated PCC uptake, while patients from gynecology showed reduced progression through the care pathway. Age, gender, income, education, marital status, and living arrangement showed no statistically robust associations. Conclusions Almost two-thirds of mentally distressed medical hospital inpatients accepted an offered PPC, indicating high acceptability. About half ultimately received a consultation, highlighting substantial attrition along the SCC pathway. Ward specialty and nationality were key determinants of PPC uptake. These findings suggest that proactive, ward-oriented consultation-liaison models embedded in routine inpatient care may improve timely and equitable access to mental healthcare, including for migrant and minority patients who are otherwise less likely to access such care. Highlights Psychosomatic-psychiatric consultation pathway of medically hospitalized inpatients 63% accepted such a consultation when offered; overall 50% reached receipt. Non-Swiss nationality increased odds of acceptance (OR 1.8) and receipt (OR 1.6). Patients at geriatrics wards showed higher, at gynecology wards lower transitions. Results support low-threshold, ward-oriented consultation-liaison models.