Do women using hormone replacement treatment have less pre-existing cardiovascular risk

Several studies have suggested that women who choose to use hormone replacement therapy (HRT) already, before starting this therapy, have a better cardiovascular risk profile than those who do not use it. Some of these studies contain factors of confusion and biases, such as HRT users' greater educational achievement or physical activity, which could have led to wrong conclusions.

To study a cohort, without confounding factors in order to analyse whether the cardiovascular risk profile is different in women who choose to use HRT.

Coronary risk factors of 387 women between 45 and 64 were studied. This study was carried out at the Unit for the Preventive Medical Examination of the South Metropolitan Health Service in Santiago (Chile) during the annual check-up. The first evaluation was in 1991-1992; with a second evaluation 5 years later. Of all the women, 174 (45%) never received hormones (Group A), 124 (32%) were HRT users at the time (Group B), and 89 (23%) were former-users (Group C).

No differences were found between the three groups for age, body mass index (BMI), educational background, alcohol consumption, smoking or physical activity. Blood pressure was similar in the three groups. No significant differences were found in total cholesterol (A, 221.7+/-42.2; B, 228.2+/-47.0; and C, 227.3+/-44.9 mg/dl); high density lipoprotein (HDL, A, 53.5+/-13.2; B, 51.8+/-12.8; and C, 54.0+/-12.4 mg/dl); low density lipoprotein (LDL, A, 141.7+/-38.9; B, 148.5+/-43.1 and C, 148.3+/-43.8 mg/dl); triglycerides (A, 134.5+/-67.9; B, 141.0+/-66.1; and C, 127.3+/-68.5 mg/dl) and glucose plasma levels (A, 90.5+/-32.2; B, 87.7+/-15.3; and C, 85.0+/-8.8 mg/dl).

Our results suggest that women who choose to use HRT have a cardiovascular risk profile, before starting the therapy, similar to those who do not use it.