Maastricht University, GROW--School for Oncology and Developmental Biology, Department of Epidemiology, Maastricht, The Netherlands.
Environ Health Perspect. 2010 Mar;118(3):414-20. doi: 10.1289/ehp.0900782. Epub 2009 Oct 26.
Conflicting results on the relationship between the hardness of drinking water and mortality related to ischemic heart disease (IHD) or stroke have been reported.
We investigated the possible association between tap water calcium or magnesium concentration and total hardness and IHD mortality or stroke mortality.
In 1986, a cohort of 120,852 men and women aged 5569 years provided detailed information on dietary and other lifestyle habits. Follow-up for mortality until 1996 was established by linking data from the Central Bureau of Genealogy and Statistics Netherlands. We calculated tap water hardness for each postal code using information obtained from all pumping stations in the Netherlands. Tap water hardness was categorized as soft [< 1.5 mmol/L calcium carbonate (CaCO3)], medium hard (1.62.0 mmol/L CaCO3), and hard (> 2.0 mmol/L CaCO3). The multivariate case-cohort analysis was based on 1,944 IHD mortality and 779 stroke mortality cases and 4,114 subcohort members.
For both men and women, we observed no relationship between tap water hardness and IHD mortality [hard vs. soft water: hazard ratio (HR) = 1.03; 95% confidence interval (CI), 0.851.28 for men and HR = 0.93; 95% CI, 0.711.21 for women) and stroke mortality (hard vs. soft water HR = 0.90; 95% CI, 0.661.21 and HR = 0.86; 95% CI, 0.621.20, respectively). For men with the 20% lowest dietary magnesium intake, an inverse association was observed between tap water magnesium intake and stroke mortality (HR per 1 mg/L intake = 0.75; 95% CI, 0.610.91), whereas for women with the 20% lowest dietary magnesium intake, the opposite was observed.
We found no evidence for an overall significant association between tap water hardness, magnesium or calcium concentrations, and IHD mortality or stroke mortality. More research is needed to investigate the effect of tap water magnesium on IHD mortality or stroke mortality in subjects with low dietary magnesium intake.
关于饮用水硬度与缺血性心脏病（IHD）或中风相关死亡率之间的关系，已有相互矛盾的研究结果报道。
我们调查了自来水钙或镁浓度与总硬度以及 IHD 死亡率或中风死亡率之间可能存在的关联。
1986 年，一组年龄在 55-69 岁的 120852 名男性和女性提供了有关饮食和其他生活方式习惯的详细信息。通过将荷兰中央户籍和统计局的数据进行链接，确定了截至 1996 年的死亡率随访情况。我们使用从荷兰所有泵站获得的信息，为每个邮政编码计算自来水硬度。自来水硬度分为软（<1.5mmol/L 碳酸钙（CaCO3））、中硬（1.6-2.0mmol/L CaCO3）和硬（>2.0mmol/L CaCO3）。多变量病例-队列分析基于 1944 例 IHD 死亡率和 779 例中风死亡率病例以及 4114 名亚队列成员。
对于男性和女性，我们均未观察到自来水硬度与 IHD 死亡率之间存在关联（硬水与软水相比：危险比（HR）=1.03；95%置信区间（CI）为 0.85-1.28；男性 HR=0.93；95%CI 为 0.71-1.21；女性）和中风死亡率（硬水与软水相比：HR=0.90；95%CI 为 0.66-1.21；HR=0.86；95%CI 为 0.62-1.20）。对于镁摄入量最低的 20%男性，自来水镁摄入量与中风死亡率之间存在反比关系（每增加 1mg/L 摄入量 HR=0.75；95%CI 为 0.61-0.91），而对于镁摄入量最低的 20%女性，结果则相反。
我们未发现自来水硬度、镁或钙浓度与 IHD 死亡率或中风死亡率之间存在总体显著关联的证据。需要进一步研究以调查低镁饮食人群中自来水镁对 IHD 死亡率或中风死亡率的影响。
