Preadmission morbidity and healthcare utilization among older adults with potentially avoidable hospitalizations: a Danish case–control study

Abstract

Abstract Purpose Examine preadmission diagnoses, medication use, and preadmission healthcare utilization among older adults prior to first potentially avoidable hospitalizations. Methods A nationwide population-based case–control study using Danish healthcare data. All Danish adults aged ≥ 65 years who had a first potentially avoidable hospitalization from January 1995 through March 2019 (n = 725,939) were defined as cases, and 1:1 age- and sex-matched general population controls (n = 725,939). Preadmission morbidity and healthcare utilization were assessed based on a complete hospital diagnosis history within 10 years prior, and all medication use and healthcare contacts 1 year prior. Using log-binomial regression, we calculated adjusted prevalence ratios (PR) with 95% confidence intervals (CI). Results Included cases and controls had a median age of 78 years and 59% were female. The burden of preadmission morbidity was higher among cases than controls. The strongest associations were observed for preadmission chronic lung disease (PR 3.8, CI 3.7–3.8), alcohol-related disease (PR 3.1, CI 3.0–3.2), chronic kidney disease (PR 2.4, CI 2.4–2.5), psychiatric disease (PR 2.2, CI 2.2–2.3), heart failure (PR 2.2, CI 2.2–2.3), and previous hospital contacts with infections (PR 2.2, CI 2.2–2.3). A high and accelerating number of healthcare contacts was observed during the months preceding the potentially avoidable hospitalization (having over 5 GP contacts 1 month prior, PR 3.0, CI 3.0–3.0). Conclusion A high number of healthcare contacts and preadmission morbidity and medication use, especially chronic lung, heart, and kidney disease, alcohol-related or psychiatric disease including dementia, and previous infections are strongly associated with potentially avoidable hospitalizations.