Trends and patterns of cause-specific hospitalizations in mainland Portugal between 2000 and 2016

This study aimed to describe trends and patterns of cause-specific hospitalizations in mainland Portugal between 2000 and 2016. This was a retrospective observational study based on hospital discharge data during the period 2000–2016 in mainland Portugal. All inpatient hospital discharges among mainland Portuguese public hospitals were considered to evaluate trends and patterns over the years through hospitalization proportions, number of hospitalizations, age-standardized hospitalization rates (direct standardization using the European standard population), and the number of in-hospital stay days (bed-days). Health Cost and Utilization Project Clinical Classifications Software was used to categorize and cluster inpatients’ principal diagnosis. Between 2000 and 2002 and between 2014 and 2016, age-standardized hospitalization rates decreased by 8.6%. Moreover, “liveborn,” “diseases of the heart,” and “respiratory infections” were the leading hospitalization causes in both periods with a variation of −8.8%, −8.3%, and 13.4% on age-standardized hospitalization rate, respectively. The age-standardized hospitalization rate due to “bacterial infection” increased by 108.7%. “Respiratory diseases” are the leading cause responsible for more in-hospital stay days in the period 2014–2016 (48.6% increase). All Portuguese regions presented decreasing overall trends in their age-standardized hospitalization rates in the study period, yet increasing trends were observed until 2004 except for the Lisbon region; in addition, the number of in-hospital stay days remained relatively stable through time. Hospitalizations in mainland Portugal decreased between 2000 and 2016 with heterogeneous patterns considering time, age group, and gender. “Aspiration pneumonitis; food/vomitus,” “diseases of the white blood cells,” “other nutritional, endocrine, and metabolic disorders,” “bacterial infection,” and “pathological fractures” revealed substantial increases, and further evaluations and monitoring are required.