Endocrine Abstracts

It is well known that there exists a correlative relationship between diabetes mellitus (DM) and sex hormone levels. However, it has not yet been found if it is caused either by hyperinsulinemia, or hyperglycemia or insulin resistance (IR). Eighty-one men with DM and 35 healthy men with normal glucose levels were examined. In each group the persons were divided into four age subgroups: 36–45 years old, 46–55, 56–65 and 66–75 years old. IR was estimated using HOMA-IR, FIRI, QUICKI and Raynaud index. As a result, it has been established that T and FTI level tend to decrease with the increasing age. As compared to men with normal insulin sensitivity the most considerable decrease was shown in healthy men aged 46–55 with IR (12.4±2.37 and 7.28±1.2 nmol/l, respectively, P<0.05) and diabetic patients with IR aged 66–75 (14.82±0.71 and 5.91±1.11 nmol/l, respectively, P<0.05). SHBG level increased with age in diabetic patients and men without diabetes mellitus. However, in diabetic patients SHBG level was shown to be lower than in men with normal blood glucose content irrespective of insulin sensitivity (P<0.05). The lowest values were registered in diabetic patients with IR aged 36–45 (P<0.05). A pronounced increase in free testosterone index (FTI) as compared to men without diabetes mellitus and diabetic patients with IR in all age groups (P<0.05) was observed in diabetic patients with normal insulin sensitivity. In other age groups low SHBG values were not accompanied by FTI increase. In the senior age group (66–75 years) SHBG levels in diabetic patients were similar to those in normal persons. A significant decrease in SHBG level was also found in men without diabetes mellitus with IR as compared to those with normal insulin sensitivity (P<0.05).

Conclusion: The most pronounced decrease in T, FTI and SHBG values is observed in diabetic patients with IR in older age groups. Low SHBG levels in diabetic patients aged 36–45 were accompanied by higher FTI values in contrast to healthy men with normal blood glucose values. The disorders found did not depend upon glycemia level, duration of the disease, the treatment given and existent complications but they were caused by insulin sensitivity.