To investigate the average and variability in urinary salt excretion in treated hypertensive outpatients during several years (median follow-up is 2 years).Design and Method:
In our previous research, the subjects were 200 hypertensive patients who underwent at least three measurement of USALT from Sep 2012 to Mar 2013. We extended the follow-up period until Aug 2015 and the subjects were 68 hypertensive patients who were measured USALT 10 times over (65.1 ± 10.2 years old, Female 32.4%). The mean of 10 times USALT and coefficient of variation (CV) for USALT were calculated and investigated the relationship with age, sex, antihypertensive medication, comorbidities.Results:
During the median period of 2 years, USALT measurement was an average of 14.8 times. Comorbidities of patients were CKD 63.2%, diabetes mellitus 45.6%, dyslipidemia 55.9% and hyperuricemia 54.5%, respectively. The subjects who have complication or past history of vascular disease (ex. Brain infarction) were 36.8%. The average of USALT until 10 times was 8.66 g/day and CV of USALT (median) was 16.6%. Subjects in large USALT group (≧ 8.66 g/day) were higher BMI (26.0 v.s 24.1 Kg/m2, p < 0.05), lower HDL-C (45.1 v.s 51.5 mg/dl, p < 0.05), more often be prescribed with α 1-blockers (44.1 v.s 20.6%, p < 0.05) and diuretics (35.3 v.s 11.8%, p < 0.05) than small USALT group (< 8.66 g/day). There are more female than men (48.5 v.s 17.1%, P < 0.05) and tendency to have a vascular disease (45.5 v.s 25.7%, P = 0.09) in high CV of USALT group (≧ 16.7%) than low group (< 16.7%).Conclusions:
This study show that the average of USALT was related to BMI and drug-resistant hypertension in accordance with past report. In addition, sex is possible to be associated with variability of USALT during 2 year follow-up.