Obesity in boys and girls: clinical, biochemical and metabolic differences
The objective. To study clinical, biochemical and metabolic specificities of obesity in boys and girls and to reveal the main differences in the course of this disease depending on gender. Patients and methods. We examined 537 obese children aged 2-17 years: 215 boys (group 1) and 322 girls (group 2); the groups are comparable by age. A comparative evaluation of clinical, medical history and anthropometric data, parameters of carbohydrate and lipid metabolism, body composition, metabologram and incidence of complications, and associated disorders was performed in the studied groups. In children younger than 5 years of age obesity was diagnosed at BMI equalling or exceeding +3.0 SDS, in children aged 5 years and older +2.0 SDS. Results. In family members of obese boys diabetes mellitus type 2 was found more often (48.4%) as compared with the girl group (35.7%), p = 0.006. The values of most anthropometric parameters were significantly higher in the boy group. The frequency of impaired carbohydrate metabolism (82.8 and 84.2%) and dyslipidemia (58.6 and 52.8%, respectively) did not differ significantly in the boy and girl groups. The level of uric acid was higher in the boy group (383 [317; 462] mmol/l) as compared with girls (333 [274; 391] mmol/l), p < 0.001. Hyperuricemia was also more often found in male patients: 49.8 vs. 38.8%, p = 0.012. The incidence of non-alcoholic fatty liver disease (NAFLD) in boys was 66.5%, in girls - 52.5% (p = 0.0013). The percentage of NASH in the structure of NAFLD was also higher in the boy group (33.6 vs. 17.2%, p = 0.0006). Body fat in 80.6% of boys exceeded the norm by 100% and more, among girls - only in 40.7% of cases (p < 0.05). Fat oxidation rate did not have significant differences in boys and girls (108.22 [55.76; 152.0] and 99.2 [50.5; 141.2] g/day), other parameters of basal metabolism were higher in the boy group: resting energy expenditure 1828 [1525; 2168] and 1562 [1286; 1894] kcal/day, carbohydrate oxidation rate 150.06 [88.88; 233.54] and 125.66 [61.31; 183.83] g/day, protein oxidation rate 62.55 [44.44; 80.57] and 55.76 [40.42; 70.1], respectively. A decrease of energy expenditure was more characteristic for boys (42.5%) than for girls (28.7%), p = 0.005. Conclusion. The results of the study are indicative of a more favourable clinical and biochemical profile in obese girls as compared with boys. The possible causes of that might be a compromised family history of diabetes mellitus type 2, and that parents are probably not alert to excessive BM in boys.