Detrimental effects of endogenous oestrogens on primary acute myocardial infarction among postmenopausal women.

objectiveTraditionally, oestrogens were considered to be protective for the cardiovascular system for premenopausal women. Therefore, we conducted a retrospective case-control study to examine the association between endogenous oestrogens and acute myocardial infarction (AMI) risk among postmenopausal women.

methodsA case-control study was performed among 30 primary AMI patients and 60 control subjects. Baseline characteristics data was collected and endogenous sex hormones levels were determined using chemoluminescence and radioimmunoassay methods. Conditional logistic regression models were developed with adjustment for confounders.

resultsCompared with controls, the circulating oestrone, oestradiol, androstenedione and testosterone levels were significantly higher in AMI patients (P < 0.05) while the sex hormone binding globulin (SHBG) level was lower (P < 0.05). Spearman correlation coefficients showed oestradiol was positively correlated with body mass index (BMI) and waist-to-hip ratio (WHR) in cases, but not in controls. In univariable conditional logistic regression models, oestrone, oestradiol, testosterone, WHR, BMI, diabetes and hypertension were all found to be positively associated with AMI (P < 0.05). After adjusting for these factors, oestradiol (odds ratio (OR) = 4.75; 95 % confidence interval (CI) = 1.07-21.10; P = 0.04) and WHR (OR = 6.46; 95 % CI = 1.09-38.39; P = 0.04) continued to demonstrate strong positive associations with AMI.

conclusionsA higher level of oestradiol was potentially associated with primary AMI risk among postmenopausal women.