Sex differences in coronary atherosclerosis during the pre- and postmenopausal period: The Tampere Sudden Death Study

Background and aims: Women are believed to be protected from coronary heart disease (CHD) by the effects of estrogen but detailed studies on the vessel wall level are missing. We aimed to measure sex differences in atherosclerosis during the premenopausal and postmenopausal periods directly at the coronary arteries. Methods: We analyzed statistics for sex differences in CHD mortality in Finland in 2020. Coronary atherosclerosis was measured using computer-assisted morphometry in 10-year age groups of 185 white Caucasian women and 515 men from the Tampere Sudden Death Study. Results: CHD mortality was rare in both women and men before 50 years of age. After 50 years of age, male mortality increased rapidly, with women reaching equal levels in the oldest age groups. In the autopsy series, there were no differences in fatty streak, fibrotic or calcified plaque areas, nor in the plaque area or stenosis percentage in coronary arteries between premenopausal women and men in the same age group. The plaque area remained 25 % smaller in both coronaries in postmenopausal women aged 51-70 years compared to men. In the oldest postmenopausal group (>= 70 years), plaque area reached the level of men. In the postmenopausal period, coronary stenosis in the left anterior descending (LAD) artery remained lower among women. Conclusion: We did not detect any major sex-difference in coronary atherosclerosis in the premenopausal period when women are considered to be protected from CHD. However, in line with CHD mortality statistics, postmenopausal women showed a slower speed of coronary atherosclerosis development compared to men.