Pharmacosurveillance and Pharmacogenetics of First-line Diuretics in Hypertension: The StayOnDiur Study

Summary

Background: The use of thiazide diuretics in the treatment of hypertension (HT) is widely considered a first line treatment, given the efficacy and low cost of this class of drugs. This indication is not unanimous, because thiazides can cause metabolic alterations and other side effects increasing cardiac and cerebrovascular risk, which reduce compliance to treatment and increase health care system cost. However, large intervention trials in HT suggest that the improvement in cardiovascular prognosis of HT patients depends more on follow-up procedures than on type of drug used. Furthermore, the investigators have documented improved compliance to antihypertensive therapy by implementing cooperation between general practitioners (GPs) and HT specialists. Objectives: In a multicenter, open label randomized study the investigators will compare the persistence on therapy of thiazides versus other treatments, as a first line antihypertensive therapy, in a clinical setting characterized by a strict cooperation between GPs and HT specialist. The investigators will also analyse candidate genes with impact on drug-induced metabolic alterations to elucidate the pathophysiology of these phenomena. Methods: 260 GPs will recruit 2600 hypertensive patients with indication to pharmacological treatment and randomise them to starting treatment with chlortalidone (12.5 to 25 mg daily, 1300 pts) or a GP decided single drug (excluding thiazides) or combination therapy at highest tolerated dose. In both groups any other class of antihypertensive drugs can be added over time in order to achieve blood pressure control (\<140/90 mmHg). Follow-up will last 2 years. Blood sample and urine analyses, carotid and cardiac ultrasound will be performed at baseline and scheduled time points. Genotyping will be performed by sequencing. Data will be collected and stored using a web based centralized Case Report Form (CRF) Expected results: Results will highlight whether a follow-up strategy based on tight cooperation between GPs and HT specialists can allow the use of thiazides as first line antihypertensive therapy without any negative effect on persistence, adherence and efficacy of the treatment. These data can be used to reduce total burden of the Health Care System in HT by replacing more expensive drugs with diuretics in the 50% of hypertensive patients, who do not receive this class of drugs. Furthermore, the pharmacogenetic approach may clarify the pathophysiological mechanisms of drug-induced metabolic side effects

Timeline

Start

2006-12

Primary completion

2009-12

Completion

2010-03

Publications

• Background Nishizaka MK, Zaman MA, Calhoun DA. Efficacy of low-dose spironolactone in subjects with resistant hypertension. Am J Hypertens. 2003 Nov;16(11 Pt 1):925-30. doi: 10.1016/s0895-7061(03)01032-x.
• Chittani M, Zaninello R, Lanzani C, Frau F, Ortu MF, Salvi E, Fresu G, Citterio L, Braga D, Piras DA, Carpini SD, Velayutham D, Simonini M, Argiolas G, Pozzoli S, Troffa C, Glorioso V, Kontula KK, Hiltunen TP, Donner KM, Turner ST, Boerwinkle E, Chapman AB, Padmanabhan S, Dominiczak AF, Melander O, Johnson JA, Cooper-Dehoff RM, Gong Y, Rivera NV, Condorelli G, Trimarco B, Manunta P, Cusi D, Glorioso N, Barlassina C. TET2 and CSMD1 genes affect SBP response to hydrochlorothiazide in never-treated essential hypertensives. J Hypertens. 2015 Jun;33(6):1301-9. doi: 10.1097/HJH.0000000000000541.
• Trimarco V, Izzo R, Migliore T, Rozza F, Marino M, Manzi MV, De Marco M, de Simone G, De Luca N. Should thiazide diuretics be given as first line antihypertensive therapy or in addition to other medications? High Blood Press Cardiovasc Prev. 2015 Mar;22(1):55-9. doi: 10.1007/s40292-014-0065-0. Epub 2014 Jun 24.

Drugs

Indications