Lockdown COVID‑19: a stress test revealing more about the mental health system than psychopathology—A comparative analysis between Austria, Germany, and Italy

Background This study examined whether the COVID-19 pandemic produced diagnosis-specific and cross-nationally reproducible alterations in psychiatric admissions, or whether observed variations primarily reflected organizational responses. We compared psychiatric inpatient services from Austria and Germany—two hospital-centered systems with similar pre-pandemic structures—and used Italy as a contrasting community-based model. Methods We conducted a retrospective multicenter observational study including all psychiatric hospitalizations between 2017 and 2020. Temporal admission trends were analyzed bi-weekly for each ICD-10 diagnostic group. Generalized Linear Models (Poisson family) were used to model the effects of Diagnosis, Year (2020 vs. pre-2020), Week, and Country, and their interactions. Diagnostic categories were grouped following ICD-10, with F10 (alcohol-related disorders) analyzed separately from other substance-use disorders to capture differences between planned and emergency admissions. Results Across Austria and Germany, 2020 was associated with a marked temporal distortion in admission patterns compared with previous years (Week × Year interaction, p < 0.05), consistent across diagnoses except for F10. Alcohol-related disorders showed country-specific trajectories, reflecting service reorganization—bed closures in Austria versus stable capacity in Germany. No other diagnosis exhibited reproducible temporal deviations across countries, indicating that the pandemic affected admission organization rather than disorder-specific psychopathology. A supplementary comparison including Italy showed that, while Austria and Germany experienced a decline in total hospitalizations (−16 and −10%, respectively), Italy remained stable (+12%), suggesting greater resilience of its community-based system. Conclusion The pandemic did not induce diagnosis-specific increases in acute psychiatric admissions but substantially altered their temporal organization. Differences across countries highlight how healthcare structure—particularly the integration of territorial and inpatient services—modulates system resilience under crisis conditions.