Systematic review and meta-analysis of comorbidities and associated risk factors in Indian patients of community-acquired pneumonia.

Objective: Comorbidities and risk factors have a major implication on incidence, complications, mortality, and management of community-acquired pneumonia complications and treatment outcomes. This study attempts to identify the same in the Indian population through a systematic review and meta-analysis. Methods: We screened observational studies (between January 1990 and February 2021) that reported potential comorbidities and other factors associated with increased risk of community-acquired pneumonia in the Indian population (⩾12 years) using PubMed, Google Scholar, and manual search. The risk of bias was identified using the Joanna Briggs Institute checklist for prevalence studies. Meta-analysis was conducted by using the random intercept logistic regression model. Results: Twenty-three studies were included in this analysis. The most prevalent comorbidities were chronic obstructive pulmonary disease (24.2%; 95% confidence interval: 16.4%-34.2%), hypertension (23.7%; 95% confidence interval: 13.6%-38.1%), and diabetes mellitus (16%; 95% confidence interval: 9.9%-24.7%). The prevalence of community-acquired pneumonia was high in patients with a current or previous history of smoking (51.4%; 95% confidence interval: 42.3%-61%) and advanced age ⩾50 years: (55.8%; 95% confidence interval: 48.4%-62%). Conclusions: Comorbid conditions like chronic obstructive pulmonary disease, hypertension, and diabetes mellitus and factors like advanced age and smoking history were common risk factors for community-acquired pneumonia in the Indian population.