RT Journal Article SR Electronic T1 Incidence of cognitive impairment and dementia after hospitalisation for pneumonia: a UK population-based matched cohort study JF ERJ Open Research JO erjor FD European Respiratory Society SP 00328-2022 DO 10.1183/23120541.00328-2022 A1 Christos V. Chalitsios A1 Vadsala Baskaran A1 Rowan H. Harwood A1 Wei Shen Lim A1 Tricia M. McKeever YR 2023 UL http://openres.ersjournals.com/content/early/2023/01/26/23120541.00328-2022.abstract AB Background Survivors of common infections may develop cognitive impairment or dementia, however; the risk of these conditions in people hospitalised with pneumonia is not well-established.Methods A matched cohort study was conducted using Hospital Episode Statistics (HES) data linked to Clinical Practice Research Database (CPRD). Adults with the first ICD-10 code for pneumonia recorded in HES between 1 July 2002 and 30 June 2017 were included and up to four controls without hospitalisation for pneumonia in CPRD were matched by gender, age, and practice. Cognitive impairment and dementia incidence rates were calculated, and survival analysis was performed comparing those hospitalised with pneumonia to the general population.Results The incidence rates of cognitive impairment and dementia were 18 (95%CI 17.3 to 18.7) and 13.2 (95%CI 13 to 13.5) per 1000 person-years among persons previously hospitalised with pneumonia and the matched cohort respectively. People previously hospitalised with pneumonia had 53% higher incidence of cognitive impairment and dementia (aHR 1.53; 95% CI 1.46 to 1.61) than their matched cohort. The highest incidence was observed within 1-year of hospitalisation for pneumonia compared to the general population (aHR=1.89; 95%CI 1.75 to 2.05). Age modified the effect of hospitalisation for pneumonia on cognitive impairment and dementia such that the size of effect was stronger in people between 45 and 60 years old (pinteraction<0.0001).Conclusion Cognitive impairment and dementia are more likely to be diagnosed in people who have been hospitalised for pneumonia, especially in the first year after discharge, than in the general population.FootnotesThis manuscript has recently been accepted for publication in the ERJ Open Research. It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJOR online. Please open or download the PDF to view this article.Conflict of interest: C.V.C., V.B, R.H.H, Τ.Μ.Μ. declare no competing interests. W.S.L reports grants from National Institute for Health Research and Pfizer outside the submitted work. W.S.L is the Chair of COVID-19 Immunisation (unpaid) and the National Lead of British Thoracic Society community acquired pneumonia audit programme (unpaid).