Coronary heart disease and water hardness in Scotland--is there a relationship?

Scotland has a mortality rate from coronary disease which is one of the highest in the world. There is also a considerable variation in this mortality rate within Scotland. Data on water hardness throughout Scotland have been collected from Regional Water Authorities to see whether variations in coronary mortality rates can be explained by variations in water hardness. Analysis demonstrates a much weaker negative association than has been demonstrated in studies in other countries. The geographical variation in coronary mortality rates in Scotland cannot be explained by variations in water hardness, and weak association between these in Scotland is discussed.