Association Between Body Fat Mass and Plasma Insulin Level in the Male Patients with Idiopathic Hypogonadotropic Hypogonadism and Normal Glucose Tolerance

Male patients with idiopathic hypogonadotropic hypogonadism (IHH) characterized with low serum testosterone(T) might have higher risks of diabetes and coronary heart disease partly due to the high level of plasma insulin. Low serum T might also affect the body fat mass(BFM) in patients with IHH. However, the relationship between BFM and plasma insulin level in IHH patients has not been clearly clarified.

A total of 22 patients who were admitted to our hospital with IHH and normal glucose tolerance(NGT) confirmed by oral glucose tolerance test and 10 healthy subjects as controls were enrolled into our study. Glucose, insulin, serum T levels, HOMA-IR, HOMA-B and percentage of BFM were determined.

When compared with controls subjects, patients with IHH had significantly lower T concentrations(1.80nmol/L vs. 19.82nmol/L, P<0.001), whereas they had significantly higher BFM(31.38% vs.21.11%, P=0.004), fasting insulin level (15.86 mu/L vs. 7.65 mu/L, P=0.018), HOMA-B(293.19 vs. 120.26, P=0.016) and HOMA-IR(3.18 vs. 1.64, P=0.018). Pearson correlation revealed that BFM was correlated with fasting insulin level(r=0.63, P=0.002), HOMA-B(r=0.53, P=0.014) and HOMA-IR(r=0.47, P=0.031). Multiple linear regression revealed BFM was an independent factor of fasting insulin level(B=0.57, 95% CI:0.24∼0.90, P=0.002), HOMA-B(B=0.096, 95% CI:0.01∼0.18, P=0.030) and HOMA-IR(B=17.09, 95% CI:3.81∼30.37, P=0.014).

BFM was an independent factor of plasma insulin level in IHH patients with NGT.