This historical cohort study has provided incidence data for thyroid disease over a twenty-year period for a representative cross-sectional sample of the population, and has allowed the determination of the importance of prognostic risk factors for thyroid disease identified twenty years earlier.

SUMMARY A survey has been conducted in Whickham, County Durham, to determine the prevalence of thyroid disorders in the community. Two thousand seven hundred and seventy‐nine people (82.4% of the available sample) were seen in the survey. The prevalence of overt hyperthyroidism was 19/1000 females rising to 27/1000 females when possible cases were included, compared with 1.6–2.3/1000 males. The prevalence of overt hyothyroidism was 14/1000 females rising to 19/1000 females when possible cases were included, compared with less than 1/1000 males. The prevalence of spontaneous overt hypothyroidism (excluding iatrogenic cases) was 10/1000 females or 15/1000 females including unconfirmed cases. Minor degrees of hypothyroidism were defined on the basis of elevated serum thyrotrophin (TSH) levels in the absence of obvious clinical features of hypothyroidism. TSH levels did not vary with age in males but increased markedly in females after the age of 45 years. The rise of TSH with age in females was virtually abolished when persons with thyroid antibodies were excluded from the sample. TSH levels above 6 mu/1 were shown to reflect a significant lowering of circulating thyroxine levels and showed a strong association with thyroid antibodies in both sexes, independent of age. Elevated TSH levels (>6mu/l) were recorded in 7.5% of females and 2.8% of males of all ages. Thyroglobulin antibodies were present in 2% of the sample. Thyroid cytoplasmic antibodies were present in 6.8% of the sample (females 10.3%, males 2.7%) and their frequency did not vary significantly with age in males but increased markedly in females over 45 years of age. 3% of the sample (females 5.1%, males 1.1%) had thyroid antibodies and elevated TSH levels and the relative risk of a high TSH level in subjects with antibodies was 20:1 for males and 13:1 for females, independent of age. Small goitres (palpable but not visible) were found in 8.6% of the sample and obvious goitres (palpable and visible) in 6.9%. Goitres were four times more common in females than in males and were most commonly found in younger rather than older females. TSH levels were slightly but not significantly lower in those with goitre than in those without goitre. There was a weak association between goitre and antibodies in females but not males.

Buckton KE, O'Riordan ML, Ratcliffe SG, et al. A G-banded study of chromosomes in liveborn infants. Ann Hum Genet 1980;43 :227-39. 5 Gosden CM, Wright MO, Paterson WG, Grant KA. Clinical details, cytogenetic studies and cellular physiology of a 69,XXX fetus with comments on the biological effect of triploidy in man. J Med Genet 1976; 13:371-80. 6 Gosden CM, Brock DJH. Morphology of rapidly adhering amniotic fluid cells as an aid to the diagnosis of neural tube defects. Lancet 1977;i: 919-22. 7 Gosden CM, Brock DJH. Combined use of alphafetoprotein and amniotic fluid cell morphology in early prenatal diagnosis of fetal abnormalities.

SUMMARY 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.