LIPID PROFILES AND CARDIOVASCULAR DISEASE IN THE WHICKHAM AREA WITH PARTICULAR REFERENCE TO THYROID FAILURE

The age and sex distribution of ischaemic heart disease (IHD), other vascular disorders and serum lipid concentrations and the possible association between these factors and thyroid failure have been examined in a community survey. A past history of IHD occurred in 7.5% of males and 4.8% of females.‘Chest pain on effort’was found in 7.4% of males and 7.8% of females and‘possible infarction’in 5.4% of males and 3.8% of females. Major ECG changes were found in 4.7% of both sexes and minor changes in 6.5% of males and 11% of females. Intermittent claudication was present in 4.8% and cerebrovascular accidents had occurred in 2% of the sample. Diastolic blood pressures greater than 100mmHg were found in 13% of all males and 11% of all females. Cholesterol concentrations were normally distributed. Mean cholesterol rose by approximately 0.25 mmol/1/decade in both sexes to reach a maximum in the 55–64 years age group and declined slightly thereafter. Trigly-ceride values were skewed to the right and increased by 0.2 mmol/1/decade in males up to the 45–54 years age group and by 0.1 mmol/1/decade in females to a peak in the 65–74 years age group — and declined after these ages. Electrophoresis revealed Type IIa patterns in 3% of males and 9% of females, IIb in 1% of both sexes and Type IV in 13% of males and 3% of females. There was no association in males between IHD and thyroid antibodies or minor degrees of thyroid failure. There was a weak association between minor ECG changes and minor degrees of hypothyroidism (but not thyroid antibodies) in females which was independent of other variables. The significance of this observation depends upon the interpretation of the ECG abnormalities and will only be established by longitudinal studies. No association was noted between lipid concentrations and thyroid antibodies or minor degrees of hypothyroidism.