Effect of immunonutritional status, healthcare factors, and lifestyle on acute respiratory infections among under-5 children in Bangladesh

Introduction: Acute respiratory infection is a major cause of death for under-5 children in Bangladesh. We aimed to analyze the effect of immunonutritional status, healthcare factors, and lifestyle on the incidence of acute respiratory infection among under-5 children taking individual-level and contextual-level risk factors into consideration. Methods: This study recruited 200 children suffering from acute respiratory infection and 100 healthy controls matched by age, sex, and sociodemographic profile. Serum antioxidant vitamin A (retinol), vitamin C (ascorbic acid), and vitamin E (α-tocopherol) were assessed along with the impact of vaccination, socioeconomic factors, and Z-score on the incidence of acute respiratory infection. Results: Serum antioxidant vitamins were significantly lower in the acute respiratory infection children compared to the non–acute respiratory infection group. Vitamin A was found to be significantly high in acute respiratory infection children who were breastfed for more than 1 year. Vitamin E levels were found to be significantly higher in the acute respiratory infection children who were immunized. Compared to the children living in tin-shed house or huts, serum vitamin E level increased in those acute respiratory infection children who resided in apartments. Vitamin A level was significantly high in those acute respiratory infection children whose height-for-age was −2 SD and above (Z-score), and vitamin C levels were also significantly high in those acute respiratory infection children whose weight-for-height was −2 SD and below (Z-score). Conclusion: Deficiencies of antioxidant vitamins along with healthcare and lifestyle factors have a significant influence on the incidence of acute respiratory infection among under-5 children in Bangladesh.