Hospitalization Pattern for Chronic Lower Respiratory Diseases in Australia: A Retrospective Ecological Study

Background: Chronic lower respiratory diseases are among the commonest causes of hospital admission worldwide. Identifying the trends in hospital admission due to chronic lower respiratory diseases is important for public health and policy makers. Aim: The aim of this study was to examine the hospitalization profile related to chronic lower respiratory diseases in Australia during the past 21 years. Method: A retrospective ecological study was conducted using hospital admission data taken from the National Hospital Morbidity Database (NHMD). Hospital admissions data for chronic lower respiratory diseases were extracted for the period between 1998 and 2019. The Pearson Chi-square test for independence was used to estimate the variation in hospital admission rates. Results: The hospitalization rate for chronic lower respiratory diseases rate decreased by 14.4%, from 568.90 (95%CI 565.50-572.30) in 1998 to 486.95 (95%CI 484.24-489.66) in 2019 per 100,000 persons, p<0.05. Rates of same-day hospitalization for chronic lower respiratory diseases increased by 62.7% from 1998 to 2019, while rates of overnight-stay hospital admission for chronic lower respiratory diseases decreased by 23.7% from 1998 to 2019. During the study duration, the hospitalization rates for bronchiectasis and other chronic obstructive pulmonary disease increased by 120.0% and 34.7%, respectively. The hospital admissions rates for emphysema, status asthmaticus, simple and mucopurulent chronic bronchitis, bronchitis, not specified as acute or chronic, unspecified chronic bronchitis, and asthma decreased by 94.8%, 92.6%, 70.7%, 66.3%, 46.0%, and 32.3%, respectively. The rates of hospitalization among patients aged 75 years and above increased by 3.9%, while younger age groups including those aged younger than 15 years, 15-59 years, and 60-74 years showed a reduction in the rate of hospitalization by 53%, 22.8%, and 19.7%, respectively. Conclusion: Overall, the hospitalization rate for chronic lower respiratory diseases is seen to have decreased over the study period. Patients with chronic obstructive pulmonary disease (COPD) and the elderly group have a higher rate of hospitalization. Future studies are needed to investigate factors associated with the increase in the rate of hospitalization among the elderly age group.