Influência da idade e do diabetes sobre esteróides sexuais e SHBG em homens

Abstract

RESUMOPara analisar a influência de fatores clínicos, demográficos e laboratoriais sobre os níveis de esteróides sexuais e SHBG, estudamos 28 homens com diabetes tipo 2 (DM2) e 27 não-diabéticos, nos quais foram medidos o índice de massa corporal (IMC), a relação cintura quadril (RCQ) e a circunferência da cintura. Foram dosados: glicose, hemoglobina glicada, insulina, peptídeo C, estradiol, testosterona e SHBG. O índice de testosterona livre (ITL) foi calculado dividindo-se o valor da testosterona total (TT) pelo valor da SHBG. Utilizamos o índice HOMA-R como indicativo de resistência insulínica. Observamos que os diabéticos apresentavam HOMA-R mais elevado do que os não-diabéticos (4,7±2,7 vs 2,75±1,6; p= 0,04), tendência a menores níveis de TT (3400 ABSTRACT Influence of Age and Diabetes On Sex Steroids and SHBG in Men.To study the role of clinical, demographic and laboratory factors on the levels of sex steroids, we studied 28 men with type 2 diabetes (DM2) and 27 non-diabetic controls. Body mass index (BMI), waist size and waist-hip ratio (WHR) were measured in all, as well as, glucose, hemoglobin A1c, insulin, peptide C, estradiol, testosterone, and SHBG. The free testosterone index (FTI) was calculated by dividing total testosterone (TT) by SHBG. The HOMA-R index was used as a measure of insulin resistance. We found that diabetics had a higher HOMA-R than non-diabetics (4.7±2.7 vs. 2.75±1.6; p= 0.04), a tendency toward lower levels of TT (3400 [1829TT (3400 [ -7000] vs. 4267 [2097pg/ml; p= 0.07) and lower ; p= 0.02). Linear regression analysis showed that age was the only variable that affected FTI (r= 0.34, r 2 = 0.12; p= 0.01) and that HOMA-R (r= 0.54, r 2 = -0.29; p= 0.0005) and age (r= 0.50, r 2 = 0.18; p= 0.0004) influenced SHBG. We conclude that diabetes is partially responsible for lower levels of total and free testosterone in men matched for age and degree of body fat, but age was the most important determinant of lower level of androgens in men with and without diabetes.