Influence of the menopause on ischaemic heart disease and its risk factors and on bone mineral content.

A comprehensive population study of women in Gothenburg, Sweden, was carried out in 1968-69. Altogether 1462 women participated (participation rate 90.1%). Five age strata were studied, i.e. women born in 1930, 1922, 1918, 1914 and 1908. The same women were restudied in 1974-1975 (participation rate 80.3% of the initial sample and 89.1% of those participating in 1968-69). In addition, a study of bone density, using photon absorptiometry, was carried out in a systematic subsample in 1976. The median age at natural menopause in the population sample was found to be 50 years and 3 months. About 5% of women aged 44 or more had stopped menstruating after hysterectomy and a similar proportion were postmenopausal as a consequence of bilateral oophorectomy. Information is also given about the percentages of the women receiving oestrogens either as substitution therapy or as oral contraceptives. Different factors influencing the age at menopause are discussed. Smoking was found to be one of the most important of these. The influence of the menopause on ischaemic heart disease and its risk factors has been studied both cross-sectionally and longitudinally. The most striking differences were found for serum cholesterol and serum triglycerides, with higher values in postmenopausal women than in premenopausal of the same ages. For bone mineral content, higher values were observed in premenopausal or recently postmenopausal women than in women of the same ages who had been postmenopausal for a long time. The observed differences in bone mineral content could not be explained by other factors studied.