Abstract
INTRODUCTION: Childhood obesity may elevate the risk for adult obesity because of chronic inflammation and immune dysregulation; however, studies on the immune system in obese children are limited. This study aimed to investigate peripheral blood lymphocyte subpopulations in obese children and their association with metabolic markers. METHODS: This prospective study included 30 obese children (median age: 11.5 years) and 22 age-matched non-obese controls. Lymphocyte populations were compared between the two groups. Additionally, factors influencing these populations were assessed in the obese group. RESULTS: The proportion of CD4(+) T cells and the ratio of naïve to memory CD4(+) T cells were significantly lower in obese children than in non-obese children (P = 0.006 and P = 0.035, respectively). Regulatory T (Treg) cell counts were significantly higher in obese children than in non-obese children (P = 0.049). The proportion of CD4(+) memory T cells positively correlated with serum alanine aminotransferase levels. The proportion of Tregs was negatively correlated with serum insulin levels and positively correlated with blood glucose levels. The number of CD4(+) T cells and the ratio of naïve to memory CD4(+) T cells were lower in obese children with a disease duration of <5 years compared to that in non-obese children. However, obese children with a disease duration of ≥5 years had a high number of CD4(+) T cells. CONCLUSIONS: This study highlights the impact of childhood obesity on immune dysregulation. The changes in T cell subpopulations in obese children differ from those observed in obese adults and vary depend on the duration of obesity.