Associations between PCDD/Fs exposure and fasting blood glucose levels
方法 采用横断面研究，调查时间为2013年8月和2014年9月。选择湖北省某垃圾焚烧厂和钢铁铸造厂的一线工人共381名作为职业暴露组，工厂周围5 km以外的居民共381名作为对照组，对所有研究对象进行问卷资料收集以及空腹血糖的测定，以研究对象经空气吸入和食物摄入的PCDD/Fs暴露量之和作为个体PCDD/Fs暴露量。应用广义线性回归模型分析PCDD/Fs暴露量与空腹血糖水平的相关性，并对空腹血糖影响因素进行交互作用检验。
结果 职业暴露组和对照组的PCDD/Fs暴露量分别为0.22（0.13~0.48）、0.09（0.05~0.10）pgTEQ/（kg·d），空腹血糖水平分别为（5.15±0.62）、（4.90±0.71）mmol/L，差异均有统计学意义（P < 0.05）。广义线性回归模型分析结果表明，调整年龄、性别、体质量指数、吸烟、饮酒、锻炼、糖尿病患病情况和糖尿病家族史后，PCDD/Fs暴露量与人群的空腹血糖水平呈现明显的正相关关系（P趋势 < 0.05），PCDD/Fs每升高一个自然对数单位，空腹血糖水平升高0.10mmol/L。锻炼或年龄与PCDD/Fs暴露量存在交互作用（P交互 < 0.05），在缺乏锻炼者（b=0.178，95% CI：0.096~0.260）或年龄 < 40岁的人群（b=0.080，95% CI：0.015~0.145）中，空腹血糖水平随PCDD/Fs暴露量升高而升高，而在锻炼者或年龄>40岁的人中二者的关联性无统计学意义。
Background Diabetes is resulted from the interaction between environment and organism, and fasting blood glucose is an early indicator for screening diabetes. In recent years, researchers have focused on the associations of diabetes with exposure to polychlorinated dibenzo-dioxins and polychlorinated dibenzo-furans (PCDD/Fs) and blood glucose level changes, but the results are inconsistent.
Objective This study measures the exposure levels of PCDD/Fs in workplaces and living environments in a city of Hubei Province, and investigates the correlation between PCDD/Fs exposure and fasting blood glucose levels.
Methods A cross-sectional study in Hubei Province was conducted in August 2013 and September 2014. The participants consisted of 381 incineration workers or foundry workers in a solid waste incinerator and a steel plant as the occupational exposure group, and 381 residents living 5 km away as the control group. Questionnaire data were collected and fasting blood glucose levels were measured. PCDD/Fs exposure levels through inhalation and food intake were summed up to represent individual PCDD/Fs exposure level. Generalized linear regression models were used to examine the correlation between PCDD/Fs exposure and fasting blood glucose levels, and interaction tests were performed with considering selected influencing factors of fasting blood glucose.
Results The PCDD/Fs exposure levelM (P25-P75) in the occupational exposure group0.22 (0.13-0.48) pg TEQ/(kg·d) was significantly higher than that in the control group0.09 (0.05-0.10) pg TEQ/(kg·d) (P < 0.05), and so was the fasting blood glucose level(5.15±0.62) and (4.90±0.71) mmol/L, respectively, P < 0.05. The results of generalized linear regression model showed that there was a significant positive correlation between PCDD/Fs exposure level and fasting glucose level (Ptrend < 0.05), after adjusting for age, gender, body mass index, smoking, drinking, exercise, diabetes prevalence, and family history of diabetes. Each 1-unit increase in ln-transformed PCDD/Fs exposure level was associated with 0.10 mmol/L increase of fasting glucose level. Exercise or age had interaction with PCDD/Fs exposure level (Pinteraction < 0.05), as in those without exercise (b=0.178, 95%CI:0.096-0.260) or aged < 40 years (b=0.080, 95%CI:0.015-0.145), fasting blood glucose level increased with higher PCDD/Fs exposure level, and in those with exercise or aged < 40 years the associations were not significant.
Conclusion PCDD/Fs exposure level is positively correlated with fasting blood glucose level, and exercise can moderately attenuate this effect.