Benefits of a fixed-dose combination of bisoprolol and amlodipine in the treatment of hypertension in daily practice: results of more than 4000 patients

Objective: The study objective was assessing patient adherence to a fixed-dose combination (FDC) of bisoprolol and amlodipine in daily practice in patients who had been switched from the free to the fixed-dose combination prior to recruitment. Material and methods: The non-investigational study was carried out in Poland. Patients over 18 years of age with essential hypertension were recruited if they had already been switched from a free combination to the FDC at least 4 weeks prior to recruitment. Exclusion criteria included pregnancy, lactation, any contraindication to the FDC, and other antihypertensive treatment. Adherence was measured by tablet count (tablets taken divided by tablets prescribed, times 100) and defined as follows: excellent >90%, good 76-90%, moderate 51-75%, bad <= 50%. Other patient data, clinical findings and laboratory values were recorded upon availability at study start, after 3 months (voluntary) and after 6 months. Results: Data of 4288 patients (mean age: 59 years; gender: 50% each) were documented. The average daily doses of the FDC were 5.8 mg bisoprolol and 6.4 mg amlodipine. These doses differ only slightly from those of the free combination. After 3 months' treatment with the FDC, a dose increase was carried out in 113 patients for bisoprolol and in 126 for amlodipine. After 6 months of FDC treatment, 82% of the participants of the study showed excellent adherence and for a further 15% the adherence could be considered good. This strong adherence may have led to the observed reduction in systolic and diastolic blood pressure of 11% (Cohen's D efficient size 1.23). In addition, pulse pressure decreased from 58.8mm to 52.2 mm. Also in diabetic patients (21% of the cohort), further reduction of systolic blood pressure values could be achieved (mean before 150 mm, after 133), wherein the initial differences compared to patients without diabetes had disappeared. The pulse rate also changed from 75 b/min to 68 b/min under the FDC. Conclusion: These study results clearly show that the FDC leads to excellent patient adherence and therefore may result in better blood pressure control. Blood pressure control is crucial in the risk reduction of cardiovascular events. The key limitation of this study is that the study design does not allow a direct comparison of patient adherence under the free and the fixed-dose combination.