Magnesium and calcium in drinking water and death from acute myocardial infarction in women

A relation between water hardness and cardiovascular death has been shown i n previous studies. In this case control study, we investigated the levers of magnesium and calcium in drinking water and death from acute myocardial infarction among women. The study population encompassed 16 municipalities in southern Sweden. Cases were women who had died from acute myocardial inf arction between the ages of 50 and 69 years during 1982-1993 (N = 378), and controls were women who had died from cancer (N = 1,368). We obtained magn esium and calcium concentrations of the individual water sources. We divide d the subjects into quartiles and found that odds ratios (ORs) were lower a t higher levels of both magnesium and calcium. For the quartile with the hi ghest magnesium levels (greater than or equal to 9.9 mg/liter), the OR adju sted for age and calcium was 0.70 (95% confidence interval = 0.50-0.99). Fo r calcium, the adjusted OR for the quartile with the highest level (greater than or equal to 70 mg/liter) was 0.66 (95% confidence interval = 0.47-0.9 4). The results suggest that magnesium and calcium in drinking water are im portant protective factors for death from acute myocardial infarction among women.