吸烟对精液质量常规指标影响的研究

The influence of smoking on the routine parameters of semen quality

目的探讨吸烟对精液质量常规指标的影响及其影响程度。方法于2004--2006年在河北、山西、贵州、浙江和山东省选择727例合格的研究对象，其中421例为吸烟者，306例为非吸烟者。通过问卷调查方法收集对象的一般人口学特征、吸烟暴露情况以及可能的混杂因素，同时收集所有研究对象的精液标本。精液分析统一按照WHO推荐的检测方法。采用SAS8．0软件分析吸烟指标（是否吸烟、每日吸烟支数、吸烟年数及总吸烟量）对5个精液常规检测指标（精液量及精子密度、存活率、前向运动率和正常形态率）的影响及其影响程度。结果以精液常规指标是否正常为应变量，在调整可能的6个混杂因素（地区、年龄、禁欲时间、文化程度、饮酒和接触农药）后，分别按降序拟合多因素logistic回归的4个模型。多因素调整后，与不吸烟组相比，吸烟组精子存活率异常的比例明显提高（DR=1．77，95％CI：1．12。2．80）；吸烟组精子活力和形态异常的比例也显著增加，OR值分别为1．51（95％CI：1．00～2．27）、2．55（95％CI：1．68～3．88）。每日吸烟量≥20支（0R=1．70，95％CI：1．05～2．76）以及总吸烟量≥15万支（0R=1．84，95％CI：1．03～3．29）时，可引起精子密度显著下降。结论吸烟对精液质量有不良影响，大量或长期吸烟者对精液质量的影响尤为明显。

Objective To explore the effect and heaviness of smoking on the routine parameters of semen quality. Methods A total of 727 eligible subjects including 421 smokers and 306 nonsmokers were selected in 2004-2006 in Hebei, Shanxi, Guizhou, Zhejiang and Shandong provinces. Data on background information, general demographic characteristics, exposure to smoking and related confounding factors were obtained through a questionnaire survey. Semen samples of all the subjects were collected during the period of study. Parameters of semen were examined according to the manual recommended by WHO. Results Four models from the multiple logistic regression regarding the semen routine parameters were used as the dependent variables to be fitted in descending order respectively, while six confounders including area, age, abstinence time, education level, history of alcohol intake and the exposure to pesticides etc., were adjusted. Results showed that smoking could affect the sperm viability, with significantly higher proportion of abnormal sperm viability seen in the smoking group （OR=1.77, 95% CI： 1.12-2.80）. Proportions regarding the abnormal mobility and morphology of sperms in the smoking group were also significantly higher than in the control group, with OR values as 1.51 （95%CI： 1.00-2.27） and 2.55 （95%CI： 1.68-3.88） respectively. The density of sperms was significantly decreased in the smoking groups who smoked more than 20 cigarettes per day （OR = 1.70,95% CI： 1.05-2.76） or the total numbers of cigarette consumption exceeding 150 000 （OR= 1.84, 95% CI： 1.03-3.29）. Conclusion Smoking showed adverse effects on the quality of semens, especially for heavy or long-term smokers.