[Reproductive hormone levels and relevant parameters in middle-aged and older men in the urban area of Nanjing].

OBJECTIVE: To investigate the status of male reproductive health among middle-aged and older men in the urban area of Nanjing.

METHODS: We collected the laboratory results of 884 middle-aged and older men aged 55 - 89 years from the Xuanwu District of Nanjing present for routine physical examinations, including those of blood routine tests, liver and kidney function, blood glucose, blood lipid, and total prostate specific antigen (TPSA), as well as such reproductive hormone indexes as total serum testosterone (TT), free serum testosterone (fT), and sex hormone binding globulin (SHBG). We also obtained the above reproductive hormone indexes from 119 young and middle-aged men aged 20 - 39 years as controls.

RESULTS: Aging-related changes were found in the 50 percentiles of all the reproductive hormones and relevant parameters but those of TT and E2, with gradual increases in LH, FSH and SHBG and decreases in fT, TSI and fTI. Comparison of reproductive hormones and relevant parameters by Mann-Whitney U test did not show any statistically significant differences in the TT level between any two of the five age groups (20 - 39, 55 - 59, 60 - 69, 70 - 79, and > or = 80 yr) (P > 0.05) except between the control and > or = 80 yr groups and the 60 - 69 and > or = 80 yr groups (P < 0.05), nor in the E2 level between any two groups, nor in the levels of LH and FSH except between the 55 - 59 and 60 - 69 yr groups and the 70 - 79 and > or = 80 yr groups, and nor in the levels of fT and TSI except between the 55 - 59 and 60 - 69 yr groups. However, there were significant differences in the levels of SHBG and fTI between any two age groups. Spearman correlation analysis revealed that fT, TSI, and fTI were correlated negatively with aging and LH (P < 0.05, I r I > 0.5) but weakly positively with cholesterol, blood glucose and hemoglobin (P < 0.05, /r/ < 0.5), SHBG and LH positively with aging, SHBG weakly negatively with blood glucose and hemoglobin, LH weakly negatively with hemoglobin, and TT weakly negatively with aging but positively with hemoglobin.

CONCLUSION: The levels of serum testosterone, particularly that of fT, declined with aging in middle-aged and older men in the urban area of Nanjing, which may contribute to abnormal lipid metabolism, low hemoglobin and high blood glucose.