Factors influencing severity of community-acquired pneumonia

Introduction: Community-acquired pneumonia (CAP) is a common cause of morbidity and mortality in India. There is a need to understand the risk factors associated with severity of CAP in our population. This study was part of the international global initiative for methicillin-resistant Staphylococcus aureus (MRSA) pneumonia study to evaluate MRSA. Methods: A total of 100 consecutive cases of pneumonia admitted to the Department of Pulmonary Medicine in a tertiary care hospital were recruited in the study during March-July 2015. The severity of pneumonia was assessed based on the CURB-65 score. Individuals with pneumonia and CURB-65 score >2 were compared with subjects with CURB-65 score <= 2. Individuals were also evaluated for the causative organism and its resistance pattern with specific reference to the presence of MRSA. Results: Mean age of patients was 54.03 years, 66% were men. Patients were managed either in the intensive care unit (42%) or wards/high dependency unit (58%), 22% needed noninvasive ventilation and 18% needed mechanical ventilation within 24 h of admission. On multivariate analysis, prior respiratory infection (within last 1 year), obesity (body mass index >30), and alcoholism, old age (>60 years) were independently associated risk factors for severe pneumonia. There were no cases of MRSA. In 34% of cases, organisms could be identified. Most common organisms were Klebsiella (8%), influenza (8%), and Pseudomonas (5%). Conclusion: Prior respiratory infection, obesity, alcoholism, and old age (>60 years) were observed to be important risk factors for severe CAP. Prospective studies should evaluate effect of weight reduction and cessation of alcohol consumption on recurrences of pneumonia in this population and on the severity of pneumonia.