Risk Factors for Community-Acquired Pneumonia in Children with Severe Acute Malnutrition in N'Djamena, Chad

Background: Community-acquired pneumonia remains a leading cause of child mortality in sub-Saharan Africa. Severe acute malnutrition (SAM) increases susceptibility to respiratory infections and worsens clinical outcomes. In Chad, evidence on pneumonia risk factors among malnourished children is scarce. This study aimed to identify factors associated with community-acquired pneumonia in children with SAM in N’Djamena. Methods: We conducted an analytical case–control study from 1 January to 31 December 2024 at the Chad–China Friendship Hospital. Eligible participants were children aged 6–59 months with SAM. Cases were children with SAM and community-acquired pneumonia diagnosed using World Health Organization (WHO) criteria. Controls were children with SAM without pneumonia, hospitalized during the same period. Socio-demographic, nutritional, environmental, and clinical data were extracted from medical records. Multivariable logistic regression identified independent risk factors. Results: A total of 246 children with SAM were included: 108 cases (44.0%) and 138 controls (56.0%). The median age was 18 months (interquartile range [IQR] 10–32); 53.2% were male. Independent predictors of pneumonia were incomplete vaccination (adjusted odds ratio [aOR] 2.41; 95% CI 1.34–4.35), exposure to biomass smoke (aOR 3.87; 95% CI 1.72–8.73), household overcrowding (aOR 2.15; 95% CI 1.18–3.93), delay in seeking care ≥3 days (aOR 2.64; 95% CI 1.39–5.00), MUAC <110 mm (aOR 1.98; 95% CI 1.06–3.69), and malaria co-infection (aOR 1.87; 95% CI 1.01–3.45). Conclusion: Among children with SAM, pneumonia is strongly associated with modifiable and preventable factors. Strengthening routine immunization, reducing household air pollution, addressing overcrowding, promoting timely care-seeking, and integrating nutritional support with infection management are essential to reduce pneumonia-related morbidity and mortality.