People with serious mental illness are at higher risk for acute care hospitalization in Israel, 2000-2019.

Background: People with severe mental disorders have higher mortality rates and more chronic physical conditions than the general population. Recent reforms in the Israeli mental health system included reducing the number of psychiatric hospital beds ("Structural Reform"), establishing community- based rehabilitation services ("Rehabilitation Reform"), and the transfer of governmental responsibility to the Health Maintenance Organizations (HMOs) ("Insurance Reform"). We examined how these changes have impacted the physical health of people with severe mental illness as reflected in acute care hospitalizations.

Methods: Data from the National Psychiatric Case Register were linked with data from the National Hospital Discharges Database for 2000-2019. Acute care discharges from public hospitals were identified for people who had a psychiatric hospitalization with a diagnosis of severe mental illness (SMI, ICD-10 codes F10-F69 or F90-F99) within the preceding 5 years. The discharge rate of SMI patients was compared to that of the total population by age, diagnosis group, and period of hospitalization. Total and age-standardized discharge ratios (SDR) were calculated, using indirect standardization.

Results: The SDR for total acute care hospitalizations showed that discharge rates in 2016-2019 were 2.7 times higher for the SMI population than expected from the total population. The highest SDR was for external causes (5.7), followed by respiratory diseases (4.4), infectious diseases (3.9), skin diseases (3.7) and diabetes (3.3). The lowest SDR was for cancer (1.6). The total discharge rate ratio was lowest at ages 65-74 (2.2) and highest at ages 45-54 (3.2). The SDR was lowest for females at ages 25-34 (2.1) and for males at ages 18-24 (2.3). SDRs increased over the study period for all diagnoses. This increasing trend slowed at the end of the period, and between 2012-2015 and 2016-2019 there was a small decrease for skin and liver diseases, the SDR was stable for cancer and the increase was smaller for respiratory, infectious and circulatory diseases and diabetes.

Conclusion: This study showed higher hospitalization rates in people with SMI compared to the total population. These differences increased between 2000 and 2019 following the opening of alternative services in the community, possibly due to a higher likelihood of psychiatric hospitalization only for those with more severe mental disease. We recommend that general practitioners and mental health professionals in the community be made aware of the essential importance of good physical healthcare, and collaborate on health promotion and disease prevention in the SMI population.