The George Institute For Global Health
United Kingdom

Efficacy of Telmisartan 40mg and Hydrochlorothiazide 25mg Monotherapy in High Sodium Intake Patients With Mild to Moderate Hypertension(THAT Study)

Project status: 
Start date: 


This research is a multicenter randomized double-blinded parallel controlled trial targeting on high sodium intake patients with mild to moderate hypertension in China. In this research, the investigators aim to compare the antihypertensive efficacy and safety of monotherapy of routine dose angiotensin receptor antagonist telmisartan (ARB) and diuretic Hydrochlorothiazide (HCTZ) in high sodium intake patients with mild to moderate hypertension. The research will be conducted in the rural area in Hebei province, where people have a high sodium diet in their daily life. The 1400 eligible subjects will be drawn from 14 local county-level hospitals. Subjects will be randomly allocated in double-blind manner into ARB or HCTZ group to be administered telmisartan 40mg per day or hydrochlorothiazide 25mg per day respectively. The investigators will evaluate the efficacy of blood pressure control and the safety of the medicines after two weeks, one month and two months of the beginning of therapies.

The Issue

Hypertension is the main risk factor of either stroke or coronary heart disease (CHD) and over 50% of cardiovascular disease are related to the hypertension in China. In 1959, the prevalence of hypertension in China was only 5%, and this number rose to 19% in 2002. Some findings estimate that the growth speed approaches nearly 10 million new cases of hypertension per year and the total patients number is estimated to be close to 266 million in 2012 in China. In the meantime however, the control rate of hypertension is only 6.1%, which is really low. Generally speaking, the population average salt intake in China is relatively high. Exploring the efficient antihypertensive medicines and therapies towards high sodium intake population becomes significantly important to guide the clinical medication of hypertension control in high salt intake population, especially in rural area with high salt intake. Theoretically, the antihypertensive effect of diuretics increases with increasing sodium intake while the antihypertensive effect of ARBs decreases.

Project Details

The research will be conducted in the local county-level hospitals in Hebei province and 14 of them will be covered in the research. The hospitals selected should meet the following requirements: They must be second-class hospitals; every researchers enrolled should possess a smart phone with Android system; three or more hypertension patients meet the enter criteria and become eligible subjects every day; 60% or more patients should be from rural area (or have rural hukou); The laboratories must qualify the Ministry of Health Quality Certification and be able to test blood (urine) sodium, blood potassium and blood (urine) creatinine; The hospital will support the research and ensure that 60% or more research funds will be governed by hospital researchers.

All subjects brought in must meet following criteria: living in rural Hebei; Age≥18;Essential hypertension: systolic blood pressure (SBP) is between 140mmHg-179mmHg and diastolic blood pressure (DBP)<110mmHg  OR  DBP is between 90mmHg-109mmHg and SBP<180mmHg; Subjects are not using antihypertensive medicines or medicines which affect the blood pressure within a week; Subjects volunteer to be brought in the research and have signed informed consent form, given that they have understood the research content.

Hypotheses Null Hypothesis-H0: There will be no efficacy differences of lowering the systolic pressure between treating high sodium intake patients with mild to moderate hypertension with telmisartan and hydrochlorothiazide.Alternative Hypothesis-H1: There will be efficacy differences of lowering the systolic pressure between treating high sodium intake patients with mild to moderate hypertension with telmisartan and hydrochlorothiazide.

The urine samples will be used to judge the sodium intake of subjects and the blood samples will be used to evaluate the research safety.

Highlight of the study

The Electronic Data Capture (EDC) system based on mobile device has functions including recording materials transfer, setting permissions for different investigators, supervising recruiting,  grouping, information collecting for each visit, records of adverse events, examination of the data validity, logic examination, follow-up reminding and warning, evidence collecting( photo of patients, drugs and samples), procedures and responsibilities for each visit, and study process report.