Haemostatic and other risk factors for ischaemic heart disease and social class: evidence from the Caerphilly and Speedwell studies.

There are marked associations between social class and mortality from ischaemic heart disease (IHD). Using data from the Caerphilly and Speedwell Collaborative Heart Disease Studies the relationships between a number of known risk factors for IHD and social class are explored. The overall conclusions are that lipids and obesity are unlikely to play any part in explaining social differences in ischaemic heart disease. Blood pressure, particularly stystolic pressure, could be involved but the two data sets are inconsistent and associations are only shown in Speedwell. There are marked differences in the haemostatic related variables in the various social classes and the pattern of these is similar in Caerphilly and Speedwell. It is possible therefore that the class pattern of IHD is generated, in part at least, by differences in haemostatic mechanisms. These differences in haemostatic function are almost entirely due to the large social class differences in smoking habit. It is possible therefore that the class differences in IHD result from differences in smoking habit.