Gonadotropin treatment increases homocysteine levels in idiopathic hypogonadotropic hypogonadism: an indirect effect mediated by changes in body composition.

The main objective of the present study was to examine the alterations in plasma total homocysteine (tHcy) concentrations during a testosterone-deficient state and after gonadotropin treatment for 6 Months in patients with idiopathic hypogonadotropic hypogonadism (IHH). Thirty-five newly diagnosed male patients with IHH (mean age 21.34+/-1.53 years) and 29 age- and body mass index-matched healthy males (mean age 21.52+/-1.77 years) were recruited into the study. Pretreatment levels of free testosterone (1.51+/-0.66 pg/ml), estradiol (21.37+/- 4.37 pg/ml), FSH (0.91+/-0.24 IU/l) and LH (1.25+/- 0.53 IU/l) were lower than controls (25.17+/-3.06 pg/ml, 31.00+/-4.96 pg/ml, 3.14+/-1.62 IU/l and 4.83+/-1.65 IU/l respectively) (P<0.001). They increased significantly after treatment (18.18+/-1.59 pg/ml, 27.97+/- 4.25 pg/ml, 2.41+/-0.27 IU/l and 2.79+/-0.19 IU/l respectively) (P<0.001). Patients with IHH had lower tHcy levels than controls (10.14+/-1.34 and 12.58+/- 2.29 micro mol/l respectively) (P<0.001). Plasma tHcy concentrations increased significantly (12.63+/-1.44 micromol/l) after 6 months of treatment (P<0.001). As compared with the controls, pretreatment levels of serum creatinine (63.54+/-13.01 vs 82.84+/-16.69 micromol/l), hemoglobin (12.98+/-0.56 vs 13.83+/-0.71 g/dl) and hematocrit (39.29+/-2.01 vs 41.38+/-1.95%) were significantly lower (P<0.001), and they increased significantly following treatment (80.24+/-11.93 micromol/l, 13.75+/-0.49 g/dl and 41.26+/-1.78% respectively) (P<0.001). The pretreatment folic acid and vitamin B(12) levels were significantly higher in patients when compared with controls (14.87+/-5.68 vs 12.52+/-4.98 nmol/l, P=0.034 and 289.75+/-92.34 vs 237.59+/-108.17 pmol/l, P=0.002 respectively). They decreased significantly after treatment (11.29+/-3.31 nmol/l and 228.51+/-54.33 pmol/l respectively) (P<0.001). The univariate and multivariate regression analysis results showed that only changes in creatinine, creatinine clearance, vitamin B12 and folic acid were independently associated with changes in tHcy levels in patients with IHH. In conclusion, the increase in plasma tHcy concentrations following gonadotropin treatment seems to be largely independent of changes in androgen levels.