High-density lipoprotein cholesterol concentration and other serum lipids in an isolated island community free of coronary heart disease.

Fasting serum high-density lipoprotein (HDL) cholesterol, other lipid concentrations and related characteristics have been measured in 87% of 261 residents aged over 5 years on the small isolated island of Salt Cay, Turks and Caicos Isles. Only one subject, a hypertensive woman, had a major electrocardiographic Q wave abnormality, and none of the islanders had clinical coronary heart disease. These findings, together with local clinical experience indicated a low incidence of coronary heart disease in this community. Adult mean concentrations of HDL cholesterol (1.6 mmol/l) and serum total triglyceride (0.81 mmol/l) were relatively high and low respectively compared with those of men and women in North American communities. Unlike findings in North America, there was no significant sex difference in HDL cholesterol concentration apparent in adulthood and this was not explained by sex differences in alcohol consumption (positively correlated with HDL cholesterol in both sexes) or adiposity (negatively correlated with HDL cholesterol in men only). Residents who were recovering from an epidemic of mild upper respiratory infection had on average a 9% reduction in HDL cholesterol concentration compared with the remainder of the community. The lipoprotein lipid pattern in these people is consistent with a low cardiovascular risk status, and might account for the apparent absence of coronary heart disease on the island.