Dhooge Willem, van Larebeke Nicolas, Comhaire Frank, Kaufman Jean-Marc
Department of Endocrinology, Study Centre for Carcinogenesis and Primary Prevention of Cancer, University Hospital, Ghent, 185 De Pintelaan, B-9000 Ghent, Belgium.
J Androl. 2007 May-Jun;28(3):435-43. doi: 10.2164/jandrol.106.001644. Epub 2006 Dec 27.
Epidemiological studies of sperm quality are hampered by problems such as low participation rates and poor comparability of results due to methodological differences in semen analysis. More objective sperm quality-related serum markers would facilitate worldwide comparisons of male reproductive status. Our objectives were to investigate to what extent a set of hormonal indices of testicular function, previously established in a clinical setting, could predict regional variations in seminal parameters in men from the general population. We recruited 101 men aged 20-40 years from two regions in Flanders, and assessed their sperm parameters and levels of serum reproductive hormones. In one region compared to another, the participants had lower sperm counts (by 34%; P=.06), lower total sperm counts (by 41%; P=.02) and poorer sperm morphology (by 32%; P<.001), which were paralleled by significantly lower levels of free testosterone (by 11%; P=.03), while for total testosterone (T) and follicle-stimulating hormone (FSH), the differences were not significant (both P=.09) at 10% and 17%, respectively. There were no differences in inhibin B and the T to luteinizing hormone (LH) ratio, which are markers of testicular function. Receiver operating characteristic curve analysis revealed that T:LH, inhibin B, and the inhibin B/FSH ratio had significant discriminatory power between men with sperm concentrations below or above 13.5x10(6)/mL. Regional variations in the semen quality of community-dwelling individuals are not necessarily reflected in altered hormonal indices of testicular function and thus, these markers, validated in clinical settings, are not valid substitutes for the traditional semen quality assessment used in epidemiological population studies.
精子质量的流行病学研究受到多种问题的阻碍，如参与率低以及由于精液分析方法差异导致结果可比性差。更客观的与精子质量相关的血清标志物将有助于全球范围内男性生殖状况的比较。我们的目标是研究一组先前在临床环境中建立的睾丸功能激素指标在多大程度上可以预测普通人群中男性精液参数的区域差异。我们从佛兰德的两个地区招募了101名年龄在20至40岁之间的男性，并评估了他们的精子参数和血清生殖激素水平。与另一个地区相比，一个地区的参与者精子数量较低（低34%；P = 0.06），总精子数量较低（低41%；P = 0.02），精子形态较差（差32%；P < 0.001），同时游离睾酮水平显著降低（低11%；P = 0.03），而总睾酮（T）和促卵泡激素（FSH）的差异分别为10%和17%，不显著（均P = 0.09）。抑制素B以及T与促黄体生成素（LH）的比值作为睾丸功能标志物并无差异。受试者工作特征曲线分析显示，T:LH、抑制素B以及抑制素B/FSH比值在精子浓度低于或高于13.5×10⁶/mL的男性之间具有显著的鉴别能力。社区居住个体精液质量的区域差异不一定反映在睾丸功能激素指标的改变上，因此，这些在临床环境中得到验证的标志物并非流行病学人群研究中传统精液质量评估的有效替代品。
