In multivariate analysis, a past history of pneumonia (aHR 1.95, 95% CI: 1.35–2.8), chronic pulmonary disease (aHR 1.86, 1.24–2.78) and inhaled corticosteroid usage (aHR 1.78, 1.12–2.84) and hypnotic/sedative medication usage (aHR 2.06, 1.28–3.31) were identified as independent risk factors for recurrent pneumonia, whereas angiotensin converting enzyme-inhibitors usage was associated with a reduction of the risk of RP (aHR 0.22, 0.05–0.91). This evidence concerns the gene ACE and susceptibility to pneumonia measurement.