Valsartan vs. other angiotensin II receptor blockers in the treatment of hypertension: a meta-analytical approach

OBJECTIVE

To compare the efficacy of valsartan in systolic (SBP) and diastolic blood pressure (DBP) reduction with other angiotensin II receptor blockers (ARBs) in essential hypertension.

METHODS

Systematic literature search of databases between October 1997 and May 2008. Meta-analysis of short-term, double-blind, parallel group, randomised controlled trials (RCTs) for treatment of adult hypertension (DBP: 90-115 mmHg). Random-effects meta-regression adjusting for baseline blood pressure (BP) was used to analyse the data. Mean change in SBP and DBP was estimated for each individual drug and dose combination.

RESULTS

In all, 31 RCTs (n = 13,110 patients) were included in the analysis. Six studies include trial arms with candesartan, six irbesartan, 13 losartan, two olmesartan, five telmisartan and 12 valsartan. The weighted average reduction in mean SBP and DBP for valsartan 160 mg was -15.32 mmHg (95% CI: -17.09, -13.63) and -11.3 mmHg (95% CI: -12.15, -10.52) and for 320 mg was -15.85 mmHg (95% CI: -17.60, -14.12) and -11.97 mmHg (95% CI: -12.81, -11.16); these are statistically significantly greater reductions compared with losartan 100 mg, which was -12.01 mmHg (95% CI: -13.78, -10.25) and -9.37 mmHg (95% CI: -10.18, -8.54) for SBP and DBP respectively. There is evidence that valsartan 160 mg reduces SBP and DBP more than irbesartan 150 mg and reduced DBP more than candesartan 16 mg. No other statistically significant difference in efficacy is demonstrated.

CONCLUSION

Valsartan administered at 160 or 320 mg is more effective at lowering BP than losartan 100 mg and shows comparable efficacy to other ARBs in patients with essential hypertension.

Treatment preferences and medication adherence of people with Type 2 diabetes using oral glucose-lowering agents

AIMS

Medication non-adherence is particularly common in patients with Type 2 diabetes. We constructed a discrete-choice experiment to examine the relative importance of oral glucose-lowering medication features and to estimate the likely effect of effectiveness and side effects on medication adherence in patients with Type 2 diabetes in the UK and the USA.

METHODS

Preferences were elicited using a cross-sectional, web-enabled survey. Patients with a self-reported physician-made diagnosis of Type 2 diabetes, who were currently taking oral glucose-lowering medications were recruited through an existing online chronic-disease panel. In each discrete-choice question, patients were asked to choose between two hypothetical medication alternatives, each defined by improvement in glycated haemoglobin, frequency of mild-to-moderate hypoglycaemia, water retention, weight gain, mild stomach upset and medication-related cardiovascular risk. Patients were also asked to indicate how likely they would be to miss or skip doses of each hypothetical medication.

RESULTS

Two hundred and four patients in the UK and 203 patients in the USA completed the survey. Preferences did not differ between the two countries. Overall, glucose control was the most important medication feature, followed by medication-related cardiovascular risk and weight gain, respectively. Water retention was not important to patients. Weight gain and cardiovascular risk had significant negative effects on likely medication adherence.

CONCLUSIONS

While patients with Type 2 diabetes believe glucose control is important, medication side effects and risks influence patients' treatment choices. Medication-related weight gain and cardiovascular risk are significant predictors of likely medication non-adherence.