Increasing burden of community-acquired pneumonia leading to hospitalisation, 1998 to 2014

Journal article

Background. Community-acquired pneumonia (CAP) is a major cause of mortality and morbidity in many countries but few recent large-scale studies have examined trends in its incidence. Methods. Incidence of CAP leading to hospitalisation in one UK region (Oxfordshire) was calculated over calendar time using routinely collected diagnostic codes, and modelled using piecewise-linear Poisson regression. Further models considered other related diagnoses, typical administrative outcomes, and blood and microbiology test results at admission to determine whether CAP trends could be explained by changes in case-mix, coding practices, or admission procedures. Results. CAP increased by 4·2%/year (95% CI 3·6-4·8) from 1998-2008, and subsequently much faster at 8·8%/year (7·8-9·7) from 2009-2014. Pneumonia-related conditions also increased significantly over this period. Length-of-stay and 30-day mortality decreased slightly in later years, but the proportions with abnormal neutrophils, urea and C-reactive protein (CRP) did not change (p>0·2). The proportion with severely abnormal CRP (>100 mg/L) decreased slightly in later years. Trends were similar in all age-groups. S. pneumoniae was the most common causative organism found; however other organisms, particularly Enterobacteriaceae, increased in incidence over the study period (p<0·001). Conclusions. Hospitalisations for CAP have been increasing rapidly in Oxfordshire, particularly since 2008. There is little evidence that this is due only to changes in pneumonia coding, an ageing population, or patients with substantially less severe disease being admitted more frequently. Healthcare planning to address potential further increases in admissions and consequent antibiotic prescribing should be a priority.

Authors: Quan, T; Fawcett, N; Wrightson, J; Finney, J; Wyllie, D

• Publication status: Accepted
• Peer review status: Peer reviewed
• Publisher: BMJ Publishing Group
• Journal: Thorax
• Publication date: 2016-01-01
• EISSN: 1468-3296
• ISSN: 0040-6376
• Keywords: hospitalisation; incidence; electronic health record; pneumonia