Increased cardiovascular response to caffeine in perimenopausal women before and during estrogen therapy.

Perimenopause and menopause may be associated with an increased risk of cardiovascular disease, so we have investigated the cardiovascular and catecholamine response to caffeine in perimenopausal women compared to young cycling premenopausal subjects. Caffeine (250 mg per os) was administered to nine perimenopausal women and nine premenopausal women. The perimenopausal women repeated the test after 4 months of percutaneous estrogen replacement therapy. Systolic and diastolic blood pressure, pulse rate, plasma norepinephrine, epinephrine, glucose, insulin and free fatty acids were determined at 0, 15, 30, 45, 60, 90 and 120 min after caffeine administration. No differences were found in the basal values of systolic blood pressure, diastolic blood pressure, pulse rate, norepinephrine, epinephrine, insulin, glucose and free fatty acids between perimenopausal women, both before and after therapy, and premenopausal women. Caffeine induced a higher increase of systolic (F = 4.9; p < 0.05) and diastolic blood pressure (F = 4.7; p < 0.05) in perimenopausal women before and during estrogen therapy as compared with premenopausal women. Pulse rate increased significantly only in perimenopausal women before therapy (F = 6.5; p < 0.03). These data show that perimenopause either before or during short-term estrogen therapy is associated with enhanced cardiovascular reactivity to caffeine. This phenomenon is not due to increased adrenergic and metabolic responses.