Risk Factors for Community-Acquired Pneumonia in Children under Five in the Post-Pneumococcal Vaccine Era in Lahore, Pakistan: A Case-Control Study

Background And Objective: Childhood pneumonia remains a leading cause of morbidity and mortality, particularly in resource-limited settings such as Pakistan. This study aimed to determine the risk factors influencing the severity of community-acquired pneumonia in children under five years of age in Punjab Province, Pakistan.
Methods: A case-control study was conducted at Mayo Hospital, Lahore, Pakistan, involving 126 children aged 2–59 months, including 63 cases diagnosed with community-acquired pneumonia and 63 controls. Data were collected through structured interviews and medical record reviews covering clinical, environmental, and socio-demographic variables. Logistic regression analysis was performed using SPSS version 26 to identify factors associated with pneumonia severity. Statistical significance was set at p < 0.05.
Results: Out of 126 participants, several factors were significantly associated with severe pneumonia. These included low family income (adjusted odds ratio [AOR] = 3.97, p = 0.006), prematurity (AOR = 10.6, p < 0.001), male gender (AOR = 3.59, p = 0.010), severe stunting (AOR = 1.24, p = 0.007), and household overcrowding (AOR = 9.1, p < 0.001). Exclusive breastfeeding showed a modest association (AOR = 1.58). Interestingly, older children from relatively higher-income households also demonstrated increased odds of severe pneumonia, suggesting a complex interaction of socioeconomic and environmental determinants. Prior healthcare utilization and nutritional status further contributed to disease severity.
Conclusion And Implications For Translation: The study highlights that severe childhood pneumonia is influenced by a combination of biological, nutritional, and socioeconomic factors. Early identification of high-risk children, improved nutrition, reduction of household overcrowding, and strengthened care-seeking behaviors are essential to reduce disease burden. These findings support the need for targeted public health interventions and context-specific preventive strategies to improve child health outcomes in Pakistan.

Childhood pneumonia; Risk factors; Case-control study; Pediatric respiratory infections

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