Body composition in children with cystic fibrosis and its association with polymorphic variants of energy metabolism genes

The aim of this prospective comparative study was to search for variants of ACE, PPARGC1A, ACTN3, PPARA genes associated with nutritional status and body composition of children with cystic fibrosis (CF). Methods. Patients with CF (F508del/F508del) (n = 425) of 0 to 18 years old (the average age was 11.8 ± 3.8 years) were included in the study to assess their BMI, polymorphic gene variants, and body composition (for children over 5 years old) before and after 1 year of targeted therapy. The percentage (%) of active cellular body mass (ACM), skeletal muscle mass (SMM) and fat mass (FM) were assessed by Z-score. Single nucleotide polymorphisms (SNPs) of the ACE gene (rs1799752), the PPARGC1A gene (rs8192678), the ACTN3 gene (rs1815739), and the PPARA gene (rs4253778) were tested by PCR and RFLP analysis. Results. After a 1 year of targeted therapy, the body weight in boys significant raised by 5.3 (±2.5) kg, height by 5.7 (±1.7) cm (p < 0.01) and the body weight in girls increased by 4.5 (±1.9) kg, height by 4.8 (±1.3) cm (p < 0.01). The boys showed an raise in FM (%) from –0.23 to 0.13 SD (p = 0.04). In girls, the FM (%) increased from –0.15 to 0.08 SD (p = 0.02) and the % SMM lowered from 0.79 to 0.6 SD (p = 0.04). The RR genotype of the ACTN3 gene was associated with BMI deficiency (p = 0.048). Patients with the GA genotype of the PPARGC1A gene tended to have decreased ACM (%) (–1.1 – 2 SD) (p = 0.071) and very low ACM (%) (< –2.1 SD) (p = 0.062). Conclusion. An analysis of body composition in children with CF showed an increase in the proportion of fat mass after 1 year of targeted therapy. The RR genotype of the ACTN3 gene was associated with BMI deficiency.