Place of Birth and Adult Cardiovascular Disease: The British Regional Heart Study

Abstract

Coronary heart disease (CHD) is almost certainly a nutritional disorder related to the quality and quantity of dietary fats and mediated by blood and tissue lipid concentrations. There is current controversy as to when the underlying process of atherosclerosis is initiated and whether the critical susceptibility to CHD may be established in utero or infancy. Blood pressure and hypertension may also be nutritionally based, and the age at which the rate of rise in blood pressure with age is determined is also controversial. The British Regional Heart Study (BRHS) involves 7,735 middle-aged men from 24 towns in England, Wales and Scotland and reveals that average blood cholesterol levels in these towns show no relationship to CHD mortality but all are high by international standards. Blood pressure levels vary markedly between the 24 towns and relate strongly to CHD mortality patterns, which are highest in Scotland and lowest in the South of England. The hypothesis relating adult blood pressures and CHD mortality to foetal and infant life circumstances has been examined using the data on birthplace and place of examination of the BRHS men. Regardless of where they were born, men living and examined in the South had lower mean blood pressures than men living in Scotland. The highest mean blood pressures were observed in Scotland, irrespective of where the men had been born. For CHD, regardless of their place of birth, men living in the South had a lower risk of CHD than men living elsewhere. The geographic zone of examination appeared to be more important than the zone of birth in determining the risk of CHD and the level of blood pressure. While patterns of nutrition during pregnancy, in infancy and childhood may be of importance for some outcomes, such as height, it seems that exposure to risk factors during adult life predominantly determine the outcome in cardiovascular disease.