Straznicky N E, Barrington V E, Branley P, Louis W J
Department of Medicine, University of Melbourne, Austin Repatriation Medical Centre, Heidelberg, Victoria, Australia.
J Hypertens. 1998 Mar;16(3):357-68. doi: 10.1097/00004872-199816030-00013.
To investigate the interactive effects of oral contraceptive pill use and dietary fat intake on cardiovascular haemodynamics and metabolic parameters in young normotensive women.
Thirty-two women participated, of whom 16 were taking oral contraceptive pills (ethinyl-oestradiol plus levonorgestrel) and 16 were age-matched and weight-matched controls not taking such pills. Subjects consumed either a high-fat or a low-fat diet for 2 weeks in an open, randomized, crossover study lasting 6 weeks. Investigations were performed at the end of each diet during the luteal phase of the menstrual cycle.
Blood pressure was measured by 24 h ambulatory recording; cardiovascular reactivity was determined by examining blood pressure responses to systemic infusions of noradrenaline and angiotensin II and to the cold pressor test; and carbohydrate metabolism was investigated by an intravenous glucose-tolerance test.
Plasma triglyceride levels were significantly higher in women taking oral contraceptive pills compared with non-users on both diets; however, responses of lipoprotein levels to the two diets did not differ between study groups (total and low-density lipoprotein cholesterol levels decreased by 15 and 17% in oral contraceptive pill users and by 14% each in non-users, on the low-fat compared with the high-fat diet). Fasting plasma insulin levels, the insulin-production response to administration of glucose (insulin area under the curve) and resting clinic and night-time systolic blood pressures were all significantly reduced on the low-fat diet, but only in non-users. Blood pressure responses to noradrenaline and maximal heart rate response to cold were significantly attenuated during the low-fat diet in oral contraceptive pill users. During the low-fat diet, resting systolic, 24 h systolic and diastolic blood pressures and insulin area under the curve were all significantly higher for women taking the oral contraceptive pills. Users of these pills also exhibited a greater systolic sensitivity to administration both of noradrenaline and of angiotensin II and had a higher plasma renin activity irrespective of dietary phase.
These results confirm that oral contraceptive pills have the potential to cause adverse effects on blood pressure, cardiovascular reactivity and the insulin-production response to administration of glucose and suggest that some of the beneficial effects of a low-fat diet on these parameters may be negated in women taking oral contraceptive pills.
研究口服避孕药的使用与膳食脂肪摄入量对年轻血压正常女性心血管血液动力学和代谢参数的交互作用。
32名女性参与研究，其中16名正在服用口服避孕药（炔雌醇加左炔诺孕酮），16名年龄和体重匹配的未服用此类药物的对照者。在一项为期6周的开放、随机、交叉研究中，受试者食用高脂肪或低脂肪饮食2周。在月经周期的黄体期，每种饮食结束时进行调查。
通过24小时动态记录测量血压；通过检查去甲肾上腺素和血管紧张素II全身输注以及冷加压试验后的血压反应来确定心血管反应性；通过静脉葡萄糖耐量试验研究碳水化合物代谢。
在两种饮食中，服用口服避孕药的女性血浆甘油三酯水平均显著高于未使用者；然而，各研究组中脂蛋白水平对两种饮食的反应无差异（与高脂肪饮食相比，口服避孕药使用者的总胆固醇和低密度脂蛋白胆固醇水平分别降低15%和17%，未使用者均降低14%）。仅在未使用者中，低脂饮食可显著降低空腹血浆胰岛素水平、葡萄糖给药后的胰岛素生成反应（胰岛素曲线下面积）以及静息诊所血压和夜间收缩压。在低脂饮食期间，口服避孕药使用者对去甲肾上腺素的血压反应和对冷刺激的最大心率反应显著减弱。在低脂饮食期间，服用口服避孕药的女性静息收缩压、24小时收缩压和舒张压以及胰岛素曲线下面积均显著较高。这些药物的使用者对去甲肾上腺素和血管紧张素II的给药也表现出更大的收缩敏感性，并且无论饮食阶段如何，血浆肾素活性均较高。
这些结果证实口服避孕药有可能对血压、心血管反应性以及葡萄糖给药后的胰岛素生成反应产生不利影响，并表明低脂饮食对这些参数的一些有益影响可能在服用口服避孕药的女性中被抵消。
