Protocol changes to the TRIUMPH study

Fixed-combination, low-dose, triple-pill antihypertensive medication versus usual care in patients with mild-to-moderate hypertension in Sri Lanka: a within-trial and modelled economic evaluation of the TRIUMPH trial

BACKGROUND

Elevated blood pressure incurs a major health and economic burden, particularly in low-income and middle-income countries. The Triple Pill versus Usual Care Management for Patients with Mild-to-Moderate Hypertension (TRIUMPH) trial showed a greater reduction in blood pressure in patients using fixed-combination, low-dose, triple-pill antihypertensive therapy (consisting of amlodipine, telmisartan, and chlorthalidone) than in those receiving usual care in Sri Lanka. We aimed to assess the cost-effectiveness of the triple-pill strategy.

METHODS

We did a within-trial (6-month) and modelled (10-year) economic evaluation of the TRIUMPH trial, using the health system perspective. Health-care costs, reported in 2017 US dollars, were determined from trial records and published literature. A discrete-time simulation model was developed, extrapolating trial findings of reduced systolic blood pressure to 10-year health-care costs, cardiovascular disease events, and mortality. The primary outcomes were the proportion of people reaching blood pressure targets (at 6 months from baseline) and disability-adjusted life-years (DALYs) averted (at 10 years from baseline). Incremental cost-effectiveness ratios were calculated to estimate the cost per additional participant achieving target blood pressure at 6 months and cost per DALY averted over 10 years.

FINDINGS

The triple-pill strategy, compared with usual care, cost an additional US$9·63 (95% CI 5·29 to 13·97) per person in the within-trial analysis and $347·75 (285·55 to 412·54) per person in the modelled analysis. Incremental cost-effectiveness ratios were estimated at $7·93 (95% CI 6·59 to 11·84) per participant reaching blood pressure targets at 6 months and $2842·79 (-28·67 to 5714·24) per DALY averted over a 10-year period.

INTERPRETATION

Compared with usual care, the triple-pill strategy is cost-effective for patients with mild-to-moderate hypertension. Scaled up investment in the triple pill for hypertension management in Sri Lanka should be supported to address the high population burden of cardiovascular disease.

FUNDING

Australian National Health and Medical Research Council.

Process evaluation of a randomised controlled trial of a pharmacological strategy to improve hypertension control: protocol for a qualitative study

INTRODUCTION

Globally, the prevalence of uncontrolled hypertension is high, particularly in low- and middle-income countries. There is a critical need for strategies to improve hypertension control. The early use of a fixed low-dose combination of three antihypertensive drugs (triple pill) has the potential to significantly improve hypertension control. The TRI ple Pill vs. U sual care M anagement for P atients with mild-to- moderate H ypertension (TRIUMPH) randomised controlled trial (RCT) is designed to test the effects of this strategy compared with usual care in patients with mild-to-moderate hypertension. This paper reports the protocol of a process evaluation of the TRIUMPH RCT. The objectives are to understand factors related to implementation of the intervention, mechanisms of effect, contextual factors that underpin the effectiveness of the triple pill strategy and the potential barriers and facilitators to implementing the strategy in clinical practice.

METHODS AND ANALYSIS

Face-to-face semistructured in-depth interviews with a purposive sample of TRIUMPH RCT participants and healthcare professionals in Sri Lanka will be conducted. Healthcare professionals will include physicians and their staff who were involved in conducting the TRIUMPH RCT. Interviewees will be recruited sequentially until thematic saturation is achieved. Interviews will be audio recorded, transcribed verbatim and analysed in NVivo using framework analysis methods.

ETHICS AND DISSEMINATION

The TRIUMPH RCT and process evaluation have received approval from the relevant Ethics Review Committee. All participants will be asked to provide written consent before participation. Findings from the study will be disseminated through publications and conference presentations.

TRIAL REGISTRATION NUMBER

ACTRN12612001120864 , SLCTR/2015/020 ; Pre-results.

Fixed Low-Dose Triple Combination Antihypertensive Medication vs Usual Care for Blood Pressure Control in Patients With Mild to Moderate Hypertension in Sri Lanka: A Randomized Clinical Trial

IMPORTANCE

Poorly controlled hypertension is a leading global public health problem requiring new treatment strategies.

OBJECTIVE

To assess whether a low-dose triple combination antihypertensive medication would achieve better blood pressure (BP) control vs usual care.

DESIGN, SETTING, AND PARTICIPANTS

Randomized, open-label trial of a low-dose triple BP therapy vs usual care for adults with hypertension (systolic BP >140 mm Hg and/or diastolic BP >90 mm Hg; or in patients with diabetes or chronic kidney disease: >130 mm Hg and/or >80 mm Hg) requiring initiation (untreated patients) or escalation (patients receiving monotherapy) of antihypertensive therapy. Patients were enrolled from 11 urban hospital clinics in Sri Lanka from February 2016 to May 2017; follow-up ended in October 2017.

INTERVENTIONS

A once-daily fixed-dose triple combination pill (20 mg of telmisartan, 2.5 mg of amlodipine, and 12.5 mg of chlorthalidone) therapy (n = 349) or usual care (n = 351).

MAIN OUTCOMES AND MEASURES

The primary outcome was the proportion achieving target systolic/diastolic BP (<140/90 mm Hg or <130/80 mm Hg in patients with diabetes or chronic kidney disease) at 6 months. Secondary outcomes included mean systolic/diastolic BP difference during follow-up and withdrawal of BP medications due to an adverse event.

RESULTS

Among 700 randomized patients (mean age, 56 years; 58% women; 29% had diabetes; mean baseline systolic/diastolic BP, 154/90 mm Hg), 675 (96%) completed the trial. The triple combination pill increased the proportion achieving target BP vs usual care at 6 months (70% vs 55%, respectively; risk difference, 12.7% [95% CI, 3.2% to 22.0%]; P < .001). Mean systolic/diastolic BP at 6 months was 125/76 mm Hg for the triple combination pill vs 134/81 mm Hg for usual care (adjusted difference in postrandomization BP over the entire follow-up: systolic BP, -9.8 [95% CI, -7.9 to -11.6] mm Hg; diastolic BP, -5.0 [95% CI, -3.9 to -6.1] mm Hg; P < .001 for both comparisons). Overall, 419 adverse events were reported in 255 patients (38.1% for triple combination pill vs 34.8% for usual care) with the most common being musculoskeletal pain (6.0% and 8.0%, respectively) and dizziness, presyncope, or syncope (5.2% and 2.8%). There were no significant between-group differences in the proportion of patient withdrawal from BP-lowering therapy due to adverse events (6.6% for triple combination pill vs 6.8% for usual care).

CONCLUSIONS AND RELEVANCE

Among patients with mild to moderate hypertension, treatment with a pill containing low doses of 3 antihypertensive drugs led to an increased proportion of patients achieving their target BP goal vs usual care. Use of such medication as initial therapy or to replace monotherapy may be an effective way to improve BP control.

TRIAL REGISTRATION

anzctr.org.au Identifier: ACTRN12612001120864; slctr.lk Identifier: SLCTR/2015/020.