REVIEW ARTICLE Use of ACE inhibitors and risk of community-acquired pneumonia: a review Petros I. Rafailidis & Dimitrios K. Matthaiou & Ioannis Varbobitis & Matthew E. Falagas Received: 19 December 2007 / Accepted: 26 January 2008 / Published online: 5 March 2008 # Springer-Verlag 2008 Abstract Background The administration of angiotensin-converting enzyme (ACE) inhibitors has been suggested as an alternative strategy for lowering the risk of community- acquired pneumonia (CAP) in the elderly, especially in patients with neurological and cerebrovascular comorbidity. Methods We critically examined the relevant data from studies regarding the impact of ACE inhibitors in lowering the risk of CAP and/or mortality due to CAP in the elderly. We searched PubMed, Cochrane Database, and references of initially retrieved articles, and http://clinicaltrials.gov for ongoing trials. Results We identified 285 evaluable studies. Fourteen studies met the inclusion criteria and were evaluated further, of which seven were prospective studies, two randomized controlled trials, and five retrospective studies. Eight of ten studies including patients of Asian origin demonstrated a statistical significance in favor of ACE inhibitors. On the contrary, only one of five studies including patients of non-Asian origin demonstrated results in favor of ACE inhibitors. Conclusion The available data suggest that ACE inhibitors may contribute to the reduction of the risk of CAP. Never- theless, clinical data are scarce and mainly comprise studies including patients of Asian origin. As there seem to be differences regarding the genetic polymorphism of ACE among patients of different origins, future studies are needed that incorporate relevant genetics data that may help clarify the role, if any, of ACE inhibitors in preventing CAP. Keywords CAP . Angiotensin-converting enzyme . Captopril . Hypertension . Stroke . Mortality Introduction Community-acquired pneumonia (CAP) is one of the most frequent diagnoses and one of the leading causes of mor- tality, especially among elderly people, despite the advent of many antimicrobials [1, 2]. Its high incidence and mortality rates are the result of comorbidities, increasing resistance to antimicrobials, illness severity, and other age-related factor, including the impairment of host defense mechanisms and neurological and cerebrovascular disorders [2, 3]. Aspiration pneumonia is a common type of pneumonia in the elderly [4, 5]. It is defined as a lower respiratory tract infection, which is caused by pathogens of the oropharyn- geal or gastric contents [6]. This type of infection is mainly correlated with disorders of the swallowing and cough reflex [1]. Unlike other factors, these disorders are not age- related [7]. Angiotensin-converting enzyme (ACE) inhibitors are pharmaceutical agents approved for treating arterial hyper- tension, preventing albuminuria due to diabetes mellitus or other cause of nephropathy, and treating left-ventricular dysfunction due to cardiac failure or after acute myocardial Eur J Clin Pharmacol (2008) 64:565–573 DOI 10.1007/s00228-008-0467-9 P. I. Rafailidis : D. K. Matthaiou : I. Varbobitis : M. E. Falagas (*) Alfa Institute of Biomedical Sciences (AIBS), 9 Neapoleos Street, 151 23 Marousi, Greece e-mail: m.falagas@aibs.gr P. I. Rafailidis : M. E. Falagas Infectious Diseases Clinic, Department of Medicine, Henry Dunant Hospital, Athens, Greece M. E. Falagas Department of Medicine, Tufts University School of Medicine, Boston, MA, USA