Impact of obesity on the clinical course of community-acquired pneumonia in adolescents

Abstract

Community-acquired pneumonia (CAP) is a significant cause of morbidity and mortality in adolescents. This stage presents physiological changes that modify lung structure, immune response, and drug metabolism. Obesity, whose prevalence is steadily increasing in this group, adds clinical complexity by inducing a chronic inflammatory state, ventilatory dysfunction, and metabolic alterations that may negatively influence disease progression. This narrative review examines the impact of adolescence, obesity, and their combination on CAP's clinical presentation, progression, and treatment. Current evidence suggests that adolescents with obesity present more frequent respiratory symptoms, oxygen desaturation, recurrent infections, increased need for ventilatory support, admission to intensive care units, prolonged hospital stays, and higher associated healthcare costs. Additionally, pharmacokinetic alterations specific to this group, such as changes in volume of distribution, hepatic metabolism, and renal clearance, may favor subtherapeutic antibiotic dosing and increase the risk of treatment failure. Both obesity and adolescence significantly modify the clinical course of CAP, increasing its severity and complicating management. However, there is still a relevant gap in the literature: most studies combine broad paediatric age groups without a differentiated analysis of the adolescent subgroup, which limits the understanding of its clinical particularities. In this context, it is proposed to consider this condition as a particular clinical phenotype that requires an approach tailored to the physiological and metabolic characteristics of adolescents with obesity.