Risk of pneumonia in patients taking statins: population-based nested case-control study

Background Community-acquired pneumonia is one of the most common causes of hospitalisation and death in older people. Recent research suggests that statins might improve the outcome of infectious diseases because of their anti-oxidative and anti-inflammatory properties. Aim To estimate the association between current statin use and the risk of community-acquired pneumonia. Design and setting Nested case-control study of 443 general practices in the UK within the QResearch (R) database. Method Individuals with newly recorded pneumonia, diagnosed between 1996 and 2006 and aged 45 years and older, were matched with up to five controls by age, sex, general practice, and calendar year Odds ratios for pneumonia associated with statin use were adjusted for smoking status, deprivation, comorbidities, use of acid-lowering drugs, influenza, and pneumococcal vaccines. Results The analysis found a decreased risk of pneumonia in patients prescribed statins in the year prior to diagnosis (adjusted odds ratio = 0.78, 95% confidence interval [CI] = 0.74 to 0.83), particularly in patients with prescriptions in the last 28 days (adjusted odds ratio = 0.68, 95% CI = 0.63 to 0.73). Atorvastatin and simvastatin had similar associations with pneumonia risk. Analysis repeated on lobar and pneumococcal pneumonia cases showed comparable results. Conclusion In this large population-based case-control study, current exposure to statins was associated with a reduced risk of pneumonia. The findings were similar to other observational population-based studies, but further randomised controlled trials are necessary before recommending statins to patients at high risk of pneumonia.