镉接触工人心血管功能研究

Cardiovascular Function in Workers Exposed to Cadmium

[目的 ]探讨镉接触对工人血压、心电图的影响及可能的作用机制 ,以保护作业工人的健康。 [方法 ]以某冶炼厂镉接触工人 86名为接触组 ,以邻近地区无镉接触史的健康工人 10 6名为对照组 ,对其血压、心电图及相关生化指标进行测定。数据经方差分析、趋势卡方检验和logistic多元回归分析 ,并计算基准剂量 (Benchmarkdose ,BMD)。 [结果 ]镉接触组工人收缩压、舒张压、高血压患病率显著高于对照组 (P <0 0 5 ) ,高血压患病率随尿镉水平增加而升高 ,有明显的剂量 反应关系 ,并得出基准剂量 2 98μg/gCr。血浆血管紧张素II、尿钠 /钾比值也随尿镉水平增高而增高。镉对高血压患病率的影响与肾功能损害与否没有显著联系。Logistic多元回归分析发现体质指数、吸烟、镉接触年限、尿镉 ,是影响高血压患病率的主要因素。接触组工人心室电压无明显改变 ,心率低于对照组 ,QRS间期和QT间期延长 ,T波及ST段改变、心动过缓等异常发生率也显著高于对照组。 [结论 ]长期接触镉可对作业工人心血管功能产生影响 ,导致血压升高 ,这可能与镉影响肾素 血管紧张素 醛固酮系统和 /或体内钾钠平衡有关。且镉可引起心电图的改变 ,可能主要是影响心室内传导。

Objective] To investigate the changes of cardiovascular function,i.e. blood pressure(BP) and electrocardiogram(ECG) in workers exposed to cadmium. [Methods] 86 cadmium exposed workers and 106 workers in the control group were investigated. Questionnaire covering individual history,occupational history,and medical history was completed. BP,ECG and related biochemical indicators were measured. [Results] Systolic blood pressure (SBP),diastolic blood pressure(DBP) and hypertension prevalence of cadmium exposed workers were significantly higher than those in the control group( P <0 05),and there was a dose response relationship between the prevalence of hypertension and urinary cadmium level. Benchmark dose(BMD) was suggested as 6 54 μg/gCr. Angiotensin II(AII) and aldosterone(ALD) in serum and the ratio of sodium/potassium in urine also increased with the increase of urinary cadmium level. Renal dysfunction had no significant effect on the prevalence of hypertension among cadmium exposed workers. Body mass index(BMI),smoking status,duration of exposure to cadmium,and urinary cadmium level were found to be the main factors influencing the prevalence of hypertension in multivariate logistic regression. Compared to the control group,the exposed workers had significantly lower heart rate,longer QRS period and QT interval,but higher incidence of changes in T wave,ST segment,and bradycardia. [Conclusion] Long time exposure to cadmium could affect the cardiovascular function in cadmium exposed workers,including elevated blood pressure,in which Renin Angiotensin Aldosterone System(RAAS) and/or sodium retention may be involved. Cadmium could also lead to changes in ECG,which may be attributed to its effect on ventricular conduction.