Objective: To investigate the association of urinary cadmium levels with peripheral leukocyte classification counts among middle-aged and older adults aged 40 to 89 years in selected areas of China. Methods: The research was based on the survey of the impact of soil quality of agricultural land on human health in typical areas conducted in 2019-2020. A total of 5 600 middle-aged and older adults aged 40 to 89 years were included by using a multi-stage stratified random sampling method. Baseline characteristics of the subjects were collected and physical examinations were performed. Random midstream urine was collected to measure urinary cadmium and urinary creatinine and fasting venous blood was collected to measure the leukocyte count, neutrophil count, lymphocyte count, monocyte count and eosinophil count. The linear mixed effect model was used to analyse the association of urinary cadmium levels with leukocyte classification counts, and the dose-response relationship between them was analyzed by using the restricted cubic spline (RCS) function. Results: The age of the subjects was (63.17±12.02) years; 2 851 (50.91%) were males; and the M (Q1, Q3) of urinary creatinine-corrected urinary cadmium levels was 2.69 (1.52, 4.69) μg/g·creatinine. After adjusting for confounding factors, the results of linear mixed effects model analysis showed that for each 1-unit increase in urinary creatinine-corrected urinary cadmium level, the percentage change [% (95%CI)] of leukocyte count and lymphocyte count was -1.70% (-2.61%, -0.79%) and -1.57% (-2.86%, -0.26%), respectively. RCS function showed a negative linear relationship between urinary creatinine-corrected urinary cadmium levels and leukocyte counts and lymphocyte counts, respectively (all Pnon-linear>0.05). Conclusion: Urinary cadmium levels are negatively associated with leukocyte count and lymphocyte count among middle-aged and older adults aged 40 to 89 years in selected areas of China.
目的： 探讨我国部分地区40~89岁中老年人尿镉水平与外周血白细胞分类计数的关联。 方法： 本研究基于2019—2020年“典型地区农用地土壤质量对人群健康影响调查”项目，采用多阶段分层随机抽样方法，共纳入5 600名40~89岁的中老年人。收集研究对象的基线特征，进行体格检查；采集随机中段尿以检测尿镉和尿肌酐；采集空腹静脉血以检测白细胞计数、中性粒细胞计数、淋巴细胞计数、单核细胞计数和嗜酸性粒细胞计数。采用线性混合效应模型分析尿镉水平与外周血白细胞分类计数的关联，并采用限制性立方样条函数探索二者之间的剂量-反应关系。 结果： 研究对象的年龄为（63.17±12.02）岁；男性为2 851名（50.91%）；尿肌酐校正后尿镉水平的M（Q1，Q3）为2.69（1.52，4.69）μg/g·肌酐。校正相关混杂因素后，线性混合效应模型分析结果显示，尿肌酐校正后尿镉水平每增加1个单位，白细胞计数和淋巴细胞计数的变化百分比［%（95%CI）］分别为-1.70%（-2.61%，-0.79%）和-1.57%（-2.86%，-0.26%）。限制性立方样条函数分析结果显示，尿肌酐校正后尿镉水平与白细胞计数、淋巴细胞计数分别呈负向线性关系（均P非线性>0.05）。 结论： 我国部分地区40~89岁中老年人尿肌酐校正后尿镉水平与白细胞计数、淋巴细胞计数呈负向关联。.