Objective: To investigate the association between serum magnesium ion level and risk of noise-induced hearing loss (NIHL) . Methods: Acohort study was performed for 7 445 workers exposed to noise in the steelmaking and steel rolling workshops of an iron and steel enterprise in Henan Province, China. The follow-up time was from January 1, 2006 to December 31, 2015. The workers with a binaural average high-frequency hearing threshold of ≥40 dB (HL) were enrolled as case group, and those with a binaural average high-frequency hearing threshold of <35 dB (HL) and a binaural average speech frequency of ≤25 dB (HL) were enrolled as control group. After being matched for age, working years of noise exposure, sex, and type of work at a ratio of 1∶1, 187 workers each were enrolled in the case group and the control group. Flame atomic absorption spectrometry was used to measure the serum magnesium ionlevel. Aconditional logistic regression analysis was performed to investigate the association of serum magnesium ion level, body mass index, cumulative noise exposure (CNE) , smoking, drinking, hypertension, and physical exercise with NIHL, as well as the association between serum magnesium ion level and risk of NIHL after the adjustment for covariants. Results: There was no significant difference in the serum magnesium ion level between the case group and the control group (24.63±7.92 mg/m(3) vs 24.91±7.33 mg/m(3), P>0.05) . Smoking (OR=1.687, 95%CI 1.090-2.613) was a risk factor for NIHL, and physical exercise (OR=0.509, 95%CI 0.325-0.796) reduced the risk of NIHL. In the workers with CNE>98 dB (A) ·year, the risk of NIHL in the workers with higher CNE was 1.305 times (95%CI 1.051-1.620) that in those with lower CNE. After the adjustment for CNE, smoking, and physical exercise, there was no significant difference in the influence of serum magnesium ion level on the risk of NIHL between the two groups (P>0.05) . Conclusion: Serum magnesium ion level may not be associated with NIHL. Increased CNE and smoking may increase the risk of NIHL and physical exercise may reduce the risk of NIHL.
目的：探讨人血清镁离子水平对噪声性听力损失（NIHL）发生风险的影响。 方法：以河南省某钢铁企业炼钢和轧钢车间的7 445名接触噪声作业工人为队列研究人群，随访时间为2006年1月1日至2015年12月31日，筛选其中双耳高频平均听阈≥40 dB（HL）的工人为病例组，选择双耳高频平均听阈<35 dB（HL）且双耳平均语频≤25 dB（HL）的工人为对照组，并严格按年龄、接噪工龄、性别、工种因素进行1∶1病例对照配对，最终选取病例组和对照组各187名工人。采用火焰原子吸收法对血清中镁离子水平进行检测，采用条件logistic回归分析，对镁离子血清水平、体质指数（BMI）、累积噪声暴露量（CNE）、吸烟、饮酒、高血压和体育锻炼与NIHL的关系，以及调整协变量后，血清镁离子水平与NIHL发生风险之间的关系进行分析。 结果：病例组血清镁离子浓度为（24.63±7.92）mg/m(3)，对照组为（24.91±7.33）mg/m(3)，差异无统计学意义（P>0.05）。吸烟是NIHL发生的危险因素（OR=1.687，95% CI：1.090~2.613）；体育锻炼可使NIHL的发生风险降低（OR=0.509，95%CI：0.325~0.796）；对于CNE>98 dB（A）·年的研究对象，高CNE者发生NIHL的风险是低CNE者的1.305倍（95%CI：1.051~1.620）；在调整CNE、吸烟和体育锻炼后，血清镁离子水平对NIHL发生风险的影响，差异无统计学意义（P>0.05）。 结论：血清镁离子水平可能与NIHL的发生无关；高CNE和吸烟可能增加NIHL的发生风险，体育锻炼可能降低NIHL的发生风险。.
Keywords: Hearing loss; Magnesium; Noise, occupational; Serum.