Kawano Y, Minami J, Takishita S, Omae T
Division of Hypertension and Nephrology, National Cardiovascular Center, Suita, Osaka, Japan.
Am J Hypertens. 1998 Oct;11(10):1141-6. doi: 10.1016/s0895-7061(98)00037-5.
An increase in potassium (K) intake may lower blood pressure (BP), but inconsistent results have been obtained in clinical trials. We studied the effects of K supplementation in hypertensive patients with monitoring of home and ambulatory BP. Fifty-five patients with essential hypertension (26 men, 29 women, 36-77 years old) participated in this study. A 4-week K supplementation period and 4-week control period were assigned in a randomized crossover manner. During the K period, the subjects were given 64 mmol/day of K as slow-release KCl tablets. Office, home, and 24-h BP, as well as serum and urinary electrolytes, were measured at the end of each period. In the control period, office, home, and 24-h BP were 151 +/- 2/88 +/- 1 (mean +/- SE), 138 +/- 1/83 +/- 1, and 137 +/- 1/81 +/- 1 mm Hg, respectively. Serum K increased from 4.15 +/- 0.04 to 4.42 +/- 0.05 mmol/L, and urinary K increased from 54 +/- 2 to 96 +/- 3 mmol/day with the K supplementation. Office, home, and 24-h BP were significantly lower in the K period than in the control period, although the differences were small (2.7 +/- 1.1/1.4 +/- 0.6, 3.6 +/- 0.9/1.7 +/- 0.5, 3.4 +/- 1.0/1.2 +/- 0.5 mm Hg, respectively). Changes in home and 24-h systolic BP with K supplementation were highly significant (P < .001), compared with office BP (P < .05). The change in 24-h systolic BP was correlated negatively with baseline BP and urinary Na/K ratio, and positively with baseline urinary K excretion. The changes in daytime and nighttime BP were comparable. These results indicate that increasing K intake lowers BP in hypertensive subjects, especially in those with higher BP and lower K intake. Our study supports the usefulness of K supplementation in the treatment of hypertension, although its antihypertensive effect may be small.
增加钾（K）摄入量可能会降低血压（BP），但临床试验结果并不一致。我们研究了在监测家庭血压和动态血压的情况下，补充钾对高血压患者的影响。55例原发性高血压患者（26例男性，29例女性，年龄36 - 77岁）参与了本研究。以随机交叉方式安排了为期4周的补钾期和4周的对照期。在补钾期，受试者每天服用64 mmol的缓释氯化钾片。在每个阶段结束时测量诊室血压、家庭血压、24小时血压以及血清和尿液电解质。在对照期，诊室血压、家庭血压和24小时血压分别为151±2/88±1（均值±标准误）、138±1/83±1和137±1/81±1 mmHg。补钾后血清钾从4.15±0.04 mmol/L升至4.42±0.05 mmol/L，尿钾从54±2 mmol/天增至96±3 mmol/天。补钾期的诊室血压、家庭血压和24小时血压均显著低于对照期，尽管差异较小（分别为2.7±1.1/1.4±0.6、3.6±0.9/1.7±0.5、3.4±1.0/1.2±0.5 mmHg）。与诊室血压相比（P < 0.05），补钾后家庭血压和24小时收缩压的变化具有高度显著性（P < 0.001）。24小时收缩压的变化与基线血压和尿钠/钾比值呈负相关，与基线尿钾排泄呈正相关。白天和夜间血压的变化相当。这些结果表明，增加钾摄入量可降低高血压患者的血压，尤其是血压较高且钾摄入量较低的患者。我们的研究支持补钾在高血压治疗中的有效性，尽管其降压效果可能较小。
