Clinical trial NCT04286802: Impact of Self-monitoring of Salt Intake by Salt Meter in Hypertensive Patients
Official title: Impact of Self-monitoring of Salt Intake by Salt Meter in Hypertensive Patients
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Hypertension
Salt; Excess
Keywords: hypertension
uncontrolled
salt, excess
salt meter
Lead sponsor: Mahidol University
Sponsor class: OTHER
First posted: 2020-02-27
Enrollment: 100
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: Hypertension is one of the most common chronic medical conditions. The concerned sequelae are the cardiovascular complications, especially acute myocardial infarction and stroke. In Thailand, the incidence of hypertension is increasing each year. Many clinical studies found that salt intake over the reference level (\>5 g/day) would result in elevated blood pressure (BP) and long-term morbidity. Dietary salt reduction campaigns were unsuccessful, in part, due to time limitation in the clinic, lacking of awareness, and the higher threshold to detect salt taste in chronic high salt ingestion. Salt meter is a device used to detect sodium content in daily food. It will facilitate monitoring and control of salt intake. The 24-hour urinary sodium excretion is an acceptable method to reflect the quantity of sodium intake. This study aimed to compare the efficacy of salt meter plus dietary education compared with education alone in terms of salt intake reduction, blood pressure, salt taste sensitivity, and vascular consequence.

Detailed description: A randomized-controlled trial was conducted in hypertensive patients whose BP was uncontrolled (systolic BP ≥140 mmHg or diastolic BP ≥90 mmHg) despite therapy or antihypertensive-naïve. Patients were randomized to receive salt meter to use in conjunction with dietary education (group A) or receive education only (group B), and were followed up for 8 weeks. Dietary education was provided by certified dietician without awareness of patients' allocation. The primary endpoint was change in 24-hour urinary sodium excretion. Changes in BP, salt taste sensitivity threshold, cardio-ankle vascular index (CAVI), as well as motivation to maintain low salt diet were also analyzed.

Eligibility criteria: Inclusion Criteria:

* Mean SBP 140-179 mmHg or mean DBP 90-109 mmHg (average 3 times)
* Diagnosed of hypertension for at least 3 months
* No adjustment of antihypertensive agents for at least 1 month
* 24h Urine sodium ≥ 90 mmol/day
* eGFR ≥ 45 ml/min/1.73 sq.m.

Exclusion Criteria:

* eGFR \< 45 ml/min/1.73 sq.m.
* UACR \> 300 mg/g
* Serum potassium \> 6.0 mmol/l
* Serum sodium \< 135 mmol/l
* Unable to collect 24-hour urine

Primary outcomes:
measure: 24-hour urinary sodium excretion
timeFrame: 8 weeks
Secondary outcomes:
measure: Change in systolic and diastolic blood pressure
timeFrame: 8 weeks
measure: Improvement in salt taste sensitivity by evaluating the salt detection or recognition thresholds
timeFrame: 8 weeks
measure: Change in cardio-ankle vascular index (CAVI)
timeFrame: 8 weeks
Other outcomes:
measure: Number of patients with hypertensive emergency
timeFrame: 8 weeks
measure: Questionnaire about motivation to maintain low salt diet
timeFrame: after 8 weeks
Locations:
city: Bangkok
country: Thailand
facility: Faculty of Medicine, Ramathibodi Hospital, Mahidol University
Study officials:
References:
citation: Mente A, O'Donnell MJ, Rangarajan S, McQueen MJ, Poirier P, Wielgosz A, Morrison H, Li W, Wang X, Di C, Mony P, Devanath A, Rosengren A, Oguz A, Zatonska K, Yusufali AH, Lopez-Jaramillo P, Avezum A, Ismail N, Lanas F, Puoane T, Diaz R, Kelishadi R, Iqbal R, Yusuf R, Chifamba J, Khatib R, Teo K, Yusuf S; PURE Investigators. Association of urinary sodium and potassium excretion with blood pressure. N Engl J Med. 2014 Aug 14;371(7):601-11. doi: 10.1056/NEJMoa1311989.
citation: Cook NR, Kumanyika SK, Cutler JA, Whelton PK; Trials of Hypertension Prevention Collaborative Research Group. Dose-response of sodium excretion and blood pressure change among overweight, nonhypertensive adults in a 3-year dietary intervention study. J Hum Hypertens. 2005 Jan;19(1):47-54. doi: 10.1038/sj.jhh.1001775.
citation: MacGregor GA, Markandu ND, Sagnella GA, Singer DR, Cappuccio FP. Double-blind study of three sodium intakes and long-term effects of sodium restriction in essential hypertension. Lancet. 1989 Nov 25;2(8674):1244-7. doi: 10.1016/s0140-6736(89)91852-7.
citation: Piovesana Pde M, Sampaio Kde L, Gallani MC. Association between Taste Sensitivity and Self-Reported and Objective Measures of Salt Intake among Hypertensive and Normotensive Individuals. ISRN Nutr. 2012 Oct 24;2013:301213. doi: 10.5402/2013/301213. eCollection 2013.
citation: Kusaba T, Mori Y, Masami O, Hiroko N, Adachi T, Sugishita C, Sonomura K, Kimura T, Kishimoto N, Nakagawa H, Okigaki M, Hatta T, Matsubara H. Sodium restriction improves the gustatory threshold for salty taste in patients with chronic kidney disease. Kidney Int. 2009 Sep;76(6):638-43. doi: 10.1038/ki.2009.214. Epub 2009 Jun 10.