BP goal achievement in patients with uncontrolled hypertension : results of the treat-to-target post-marketing survey with irbesartan

Abstract

Background and objective: Despite the fact that high BP is a leading risk factor for cardiovascular morbidity and mortality, BP goals are achieved in less than 10-30% of hypertensive patients. Irbesartan alone or in combination with hydrochlorothiazide has been shown to control BP in >70% of hypertensive patients in clinical trials. We set out to investigate the role in clinical practice of irbesartan in improving BP in uncontrolled hypertensive patients with a particular focus on patients with the metabolic syndrome through analysis of data from a post-marketing surveillance study.

Methods: A multicentre, prospective, post-marketing surveillance study was conducted over 9 months in 14 200 patients aged > or =18 years with previously uncontrolled hypertension (either receiving therapy or newly diagnosed), paying particular attention to a subgroup of patients receiving irbesartan/hydrochlorothiazide as first-line combination therapy. BP was measured by a sphygmomanometer. The main outcome measures were systolic BP (SBP) and diastolic BP (DBP) reduction, response rate (DBP reduction of > or =10mm Hg or to <90 mm Hg), and BP normalisation (SBP <140 and DBP <90 mm Hg) in patients treated with irbesartan alone or in combination with hydrochlorothiazide. Analyses per patient subgroup, previous medication and whether treatment was initiated by the treating physician as first-line combination therapy were conducted. The number and nature of adverse events were documented.

Results: Use of irbesartan 300 mg/day as monotherapy in previously uncontrolled patients resulted in a significant reduction in SBP/DBP (-26.8/-13.3mm Hg, p < 0.0001), which was comparable to the subgroup of patients with the metabolic syndrome (-26.3/-13.0mm Hg, p < 0.0001 vs baseline). Combination therapy (irbesartan 300 mg/hydrochlorothiazide 12.5mg once daily) lowered BP by -27.9/-14.2mm Hg (p < 0.0001) in previously uncontrolled patients; again the subgroup of patients with the metabolic syndrome achieved a comparable BP reduction (-27.5/-14.1mm Hg, p < 0.0001 vs baseline). Overall, no linear dose-response relationship was observed. Use of irbesartan/hydrochlorothiazide as first-line combination therapy was effective (BP normalisation rates between 65.7% and 78.6%) and safe. The mean number of antihypertensive tablets taken was reduced and after a mean period of 9 months, 92% of patients were still taking irbesartan therapy.

Conclusion: The study demonstrates that treatment with an irbesartan-based regimen for 9 months results in a strong BP reduction and is feasible as first-line combination therapy. Similar BP reductions were observed in the subgroup of patients with the metabolic syndrome. Compliance with treatment is particularly good, with >90% of patients continuing with treatment after 9 months.