Australia's hospitalization landscape over 20 years: Insights from a longitudinal ecological study

Hospitalization is an essential part of services provided in healthcare. Understanding the trends in hospital admissions is crucial for improving healthcare outcomes. However, previous research has not analyzed the trends for all causes of hospitalizations in Australia. Therefore, this study aimed to address this gap by examining the trends in all causes of hospitalizations in Australia from 1998 to 2021. This was a descriptive, temporal ecological study using publicly available data extracted from the National Hospital Morbidity Database. Hospitalization data were extracted and analyzed for the duration between 1998 and 2021. Hospitalization data were identified using the International Classification of Diseases-10 (A00-Z99). Over the study period, there were 198,696,847 reported hospital admissions in Australia. The total number of admissions increased by 1.07 times, and the rates rose by 51.5%. Same-day hospital admissions made up most cases. The most common reason for hospital admission was "factors influencing health status and contact with health services." Females represented more than half of all hospital admissions. In addition, people 65 years and older accounted for 38.6% of hospitalizations. This study shows a rising hospitalization in Australia that could reflects an aging and growing population, changes in disease patterns, technical advancements in medical technology, changes in healthcare policy, and changes in lifestyle trends. Admissions follow different trends by type, age, and gender, indicating that hospitalization needs to be addressed through individualized interventions to reduce hospitalization and improve the outcomes of patients. More studies on the individual-level are required to explore different subtypes of hospital admissions.