Columbia University Mailman School of Public Health, New York, New York, USA.
Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA.
Sci Rep. 2017 Apr 3;7:45322. doi: 10.1038/srep45322.
Ambient fine particle (PM) pollution triggers acute cardiovascular events. Individual-level preventions are proposed to complement regulation in reducing the global burden of PM-induced cardiovascular diseases. We determine whether B vitamin supplementation mitigates PM effects on cardiac autonomic dysfunction and inflammation in a single-blind placebo-controlled crossover pilot trial. Ten healthy adults received two-hour controlled-exposure-experiment to sham under placebo, PM (250 μg/m) under placebo, and PM (250 μg/m) under B-vitamin supplementation (2.5 mg/d folic acid, 50 mg/d vitamin B, and 1 mg/d vitamin B), respectively. At pre-, post-, 24 h-post-exposure, we measured resting heart rate (HR) and heart rate variability (HRV) with electrocardiogram, and white blood cell (WBC) counts with hematology analyzer. Compared to sham, PM exposure increased HR (3.8 bpm, 95% CI: 0.3, 7.4; P = 0.04), total WBC count (11.5%, 95% CI: 0.3%, 24.0%; P = 0.04), lymphocyte count (12.9%, 95% CI: 4.4%, 22.1%; P = 0.005), and reduced low-frequency power (57.5%, 95% CI: 2.5%, 81.5%; P = 0.04). B-vitamin supplementation attenuated PM effect on HR by 150% (P = 0.003), low-frequency power by 90% (P = 0.01), total WBC count by 139% (P = 0.006), and lymphocyte count by 106% (P = 0.02). In healthy adults, two-hour PM exposure substantially increases HR, reduces HRV, and increases WBC. These effects are reduced by B vitamin supplementation.
环境细颗粒物 (PM) 污染引发急性心血管事件。个体层面的预防措施被提议作为补充，以减少 PM 引起的心血管疾病的全球负担。我们在一项单盲安慰剂对照交叉试验中，确定 B 族维生素补充是否可以减轻 PM 对心脏自主神经功能障碍和炎症的影响。10 名健康成年人分别接受了两小时的对照暴露实验，分别在安慰剂、PM（250μg/m）和 PM（250μg/m）下接受 B 族维生素补充（2.5mg/d 叶酸、50mg/d 维生素 B 和 1mg/d 维生素 B）。在暴露前、暴露后和暴露后 24 小时，我们使用心电图测量静息心率 (HR) 和心率变异性 (HRV)，并使用血液学分析仪测量白细胞 (WBC) 计数。与假暴露相比，PM 暴露增加了 HR（3.8 bpm，95%CI：0.3，7.4；P=0.04）、总 WBC 计数（11.5%，95%CI：0.3%，24.0%；P=0.04）、淋巴细胞计数（12.9%，95%CI：4.4%，22.1%；P=0.005），并降低了低频功率（57.5%，95%CI：2.5%，81.5%；P=0.04）。B 族维生素补充使 PM 对 HR 的影响降低了 150%（P=0.003），低频功率降低了 90%（P=0.01），总 WBC 计数降低了 139%（P=0.006），淋巴细胞计数降低了 106%（P=0.02）。在健康成年人中，两小时的 PM 暴露会显著增加 HR，降低 HRV，并增加 WBC。这些影响可通过 B 族维生素补充来减轻。
