Association of gamma- -glutamyltranspeptidase and uric acid with anthropometric indices and metabolic risk factors in women with excessive body weight — a preliminary study

Abstract

Introduction. Obesity is strongly associated with insulin resistance, known to be related to elevated gamma-glutamyltranspeptidase activity (GGTP) and uric acid (UA) level. However, the mechanism of this relationship has not yet been clarified. We investigated the relationship of GGTP and UA with anthropometry and components of metabolic syndrome in overweight and obese young women.

Materials and methods. GGTP, UA, fasting glucose, fasting insulin, HOMA and lipids were determined inblood samples obtained from overweight (n = 24; BMI = 25–30 kg/m²) and obese (n = 28; BMI > 30 kg/m²) women aged 25–40 yrs and age-matched healthy controls (n = 38; BMI < 25 kg/m²).

Results. GGTP and UA were elevated over the upper reference values only in 19.2% and 11.5% of women from the study group, but median GGTP and UA were significantly higher in obese and overweight women compared to controls. In the whole study group, and in obese women, GGTP activity was more associated with WC, WHR and WtHR which was not found for UA. The correlations between GGTP and HOMA-IR and fasting insulin were significant for women with excessive body weight and obese women only, whereas the correlations between UA and parameters of insulin resistance in the whole study group and in obesity did not reach statistical significance. Moreover, we found significant differences in GGTP activity between women with and without insulin resistance in both the study group and obese women(p < 0.0001; p < 0.01). In the whole study group, and in obese women only, GGTP positively correlated with TC, LDL-C, TG, TC/HDL-C ratio, SBP and DBP, whereas in overweight women it only correlated with SBP. We also found that women in higher GGTP quartiles had higher concentrations of TC, LDL-C andTC/HDL-C ratio (p < 0.03; p < 0.05; p < 0.05 for quartile trend respectively).

Conclusions. GGTP activity and uric acid concentration are higher in overweight and obese women, although only GGTP activity seems to be related to anthropometric parameters, insulin resistance and atherogenic indices, essential components of metabolic syndrome in young women. GGTP activity maybe a surrogate marker of insulin resistance and metabolic syndrome.