title: Diastolic blood pressure is related to urinary sodium excretion in hypertensive Chinese patients.
abstract: We studied 70 Hong Kong Chinese patients with untreated hypertension and 47 normotensive controls. Blood pressure measurements and 24-h urine collection were performed for each patient, and were repeated 12 weeks later in 14 hypertensive patients who remained untreated. Twenty-two hypertensive patients underwent ambulatory blood pressure monitoring. The primary hypothesis tested was a correlation between diastolic blood pressure and 24-h urinary sodium excretion. In the hypertensive patients, diastolic blood pressure correlated with 24-h urinary sodium excretion (r=0.41, p<0.001), even after adjustment for age, gender, body mass index, ethanol intake and season (r=0.34, p=0.02). In normotensive controls, diastolic blood pressure did not correlate with sodium excretion (r=0.21, p=0.16). A correlation between diastolic blood pressure and sodium excretion was also observed in the patients who underwent ambulatory blood pressure monitoring (r=0.47, p=0.026), and in repeat measurements in untreated patients (r=0.60, p=0.02). Systolic blood pressure did not correlate with sodium excretion, although it increased with patient age (0.6+/-0.1 mmHg/year, p<0.001). In a multiple regression analysis with diastolic blood pressure as the dependent variable, the regression coefficient was 0.06+/-0.02 mmHg/mmol Na. The regression coefficients for ambulatory diastolic blood pressure and diastolic pressure repeated at 12 weeks were 0.07+/-0.03 and 0. 09+/-0.04 mmHg/mmol Na, respectively. Urinary sodium excretion was related to diastolic blood pressure in our hypertensive patients, accounting for 17% of the variance of diastolic blood pressure.
authors.affiliation: Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Pokfulam, Hong Kong. mycheung@hkucc.khu.hk
authors.forename: B M
authors.initials: BM
authors.lastname: Cheung
authors.forename: S P
authors.initials: SP
authors.lastname: Ho
authors.forename: A H
authors.initials: AH
authors.lastname: Cheung
authors.forename: C P
authors.initials: CP
authors.lastname: Lau
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000428:Alcohol Drinking; D001794:Blood Pressure / Q000502:physiology*; D015992:Body Mass Index; D016022:Case-Control Studies; D002681:China / Q000208:ethnology; D003404:Creatinine / Q000652:urine; D005260:Female; D006723:Hong Kong; D006801:Humans; D006973:Hypertension / Q000208:ethnology / Q000378:metabolism* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011188:Potassium / Q000652:urine; D011446:Prospective Studies; D012044:Regression Analysis; D012737:Sex Factors; D012964:Sodium / Q000652:urine*; D017673:Sodium Chloride, Dietary / Q000009:adverse effects
chemical_list: D017673:Sodium Chloride, Dietary; D012964:Sodium; D003404:Creatinine; D011188:Potassium