Obesity diagnostics in patients with hemodialysis: bioimpedansometry and caliperometry
Obesity is considered one of the most common syndromes in medical practice. Over the past 40 years, the average body mass index (BMI) has increased by 10.3 % in men and by 9.4 % in women. It is believed that obesity, diagnosed by BMI, is a significant risk factor for the development of cardiovascular diseases, and, accordingly, negatively affects a person's life expectancy. Among the methods that make it possible not only to characterize the ratio of height and body weight but to give an idea of the amount of body fat, the most popular in our country are caliperometry and bioimpedance measurement. THE AIM: to assess the possibility of interchangeability of caliperometry and bioimpedance measurement in determining body fat mass in dialysis patients.PATIENTS AND METHODS. The study involved 140 patients, including 66 men and 58 women, receiving HD treatment. In general, the surveyed group can be characterized as clinically stable. To determine the body composition, all patients underwent caliperometry using the TVES KETS 100 electronic caliper.RESULTS. Fat mass according to caliperometry data was 40.0 % in women, 30.0 % in men, p = 0.0001. According to bioimpedance measurements – 39.9 and 28.3 %, respectively, p = 0.0001. During the ROC analysis, the area under the curve for caliperometry was 0.851 (CI 0.729-0.932), for bioimpedance measurements 0.839 (CI 0.715-0.932). The correlation between the two methods in determining body fat mass in kg was Rs = 0.991 p = 0.0001, and in % Rs = 0.985 p = 0.0001. When comparing the results of determining body fat by the Bland-Altman method, the average difference between the two methods was 0.6 ± 2.3 %, the degree of discrepancy was from -4 to + 5 %. The prevalence of obesity among dialysis patients by BMI was 29.4 % among women and 19.4 % among men. However, according to the results of both caliperometry and bioimpedance measurements, the real prevalence of obesity exceeded 90 %.CONCLUSION. Diagnosing obesity by BMI does not provide an indication of the true prevalence of obesity in dialysis patients. For this purpose, it is necessary to use bioimpedance or caliperometry. Both methods give comparable results and can be considered interchangeable.