目的: 盐敏感者的血压节律更多地表现为“非勺型”。本研究探索在高盐饮食情况下,给予补钾干预是否可改善其昼夜间血压节律变化。方法: 选取49例血压正常或1级高血压个体参与为期24 d的慢性盐负荷及补钾干预试验,包括基线期调查3 d、低盐饮食（氯化钠 51.3 mmol/d）7 d、高盐饮食（氯化钠307.7 mmol/d）7 d、高盐补钾饮食（氯化钠307.7 mmol/d+氯化钾60 mmol/d）7 d,测量受试者各期的血压,收集血、尿标本,并于每个干预期末行24 h动态血压监测。结果: 49例受试者中,盐敏感个体检出率为28.6%。慢性盐负荷以后,相比较盐不敏感个体,盐敏感个体的夜间/白天血压比值升高[收缩压（systolic blood pressure, SBP）比值为（0.96±0.01）比（0.89±0.01）,P<0.01;舒张压 (diastolic blood pressure, DBP)比值为（0.96±0.01）比（0.92±0.01）,P<0.05]。补钾干预后,盐敏感个体的夜间/白天血压比值相比于高盐期下降[SBP比值为（0.91±0.01）比（0.96±0.01）,P<0.05;DBP比值为（0.91±0.01）比（0.96±0.01）,P<0.05]。结论: 补钾干预对于盐敏感个体高盐负荷下的夜间血压下降不足、昼夜节律变异具有改善作用。
Objective: Salt-sensitive subjects showed more frequently a non-dipper blood pressure pattern. This study aimed to investigate whether potassium supplement can improve the blunted nocturnal blood pressure fall in salt-sensitive patients exposed to high-salt diet. Methods: A total of 49 normotensive and mildly hypertensive Chinese patients received a study protocol of a 3 d baseline examination, 7 d low salt diet (51.3 mmol/d NaCl), 7 d high salt diet (307.7 mmol/d NaCl) and 7 d high salt diet with a potassium supplement (307.7 mmol/d NaCl and 60 mmol/d KCl). The blood pressure of the subjects was measured at the end of each period, and blood and urine samples were collected. The 24 h ambulatory blood pressure was also obtained. Results: Of all the 49 subjects, the detection rate of salt-sensitive individuals was 28.6%. The night-to-day blood pressure ratio was significantly higher in salt-sensitive subjects than in non-salt-sensitive ones during the high salt loading period (systolic blood pressure 0.96±0.01 vs 0.89±0.01, P<0.01; diastolic blood pressure 0.96±0.01 vs 0.92±0.01, P<0.05). Compared with the high-salt loading period, night-to-day blood pressure ratio was significantly decreased by potassium supplement in salt-sensitive subjects (systolic blood pressure 0.91±0.01 vs 0.96±0.01, P<0.05; diastolic blood pressure 0.91±0.01 vs 0.96±0.01, P<0.05). Conclusions: Potassium supplement can improve the blunted nocturnal blood pressure fall in salt sensitive patients exposed to high-salt diet.
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