Negative predictors of treatment success in outpatient therapy of arterial hypertension in Poland. Results of the CONTROL NT observational registry

Abstract

Background: Identification of factors interfering with adequate control of arterial hypertension (HT) in the course of antihypertensive therapy is necessary to reduce the incidence of cardiovascular disorders and optimise clinical practice guidelines. Aim: The study objective was to conduct a screening assessment of the rate of uncontrolled hypertension among hypertensive patients coming to a routine follow-up visit, and to characterise patients with inadequate control of HT in the aspect of their cardiovascular risk profile and therapeutic strategies used. Methods: The CONTROL NT registry was a nationwide observational study performed by physicians in the outpatient setting in Poland. Patient data were collected twice: between April and September 2011 and between January and August 2012. During screening, the physician completed a questionnaire with patient basic clinical information. The impact of the selected demographic and clinical parameters on treatment success defined as blood pressure (BP) lowering to < 140/90 mmHg when measured in the office at the second visit was investigated with univariate and multivariate logistic regression models. Results: In total 1288 outpatient physicians participated in the CONTROL NT registry. In the screened group of 34,919 patients with a history of HT, 66.9% had abnormal BP readings in the office. In 15,262 patients with inadequate control of hypertension included in further analysis, the mean age was 59.3 ± 11.9 years, 47.9% were women, the disease duration was 8.2 ± 6.5 years and antihypertensive therapy was used for 7.4 ± 6.0 years. At least three cardiovascular risk factors were found in 46% of patients, with the most common dyslipidaemia (77.4%) and abdominal obesity (74.8%). In 56.6% of patients at least one concomitant disease was diagnosed, the most common being diabetes (29.8%). At the time of enrolment 21.5% of patients received no antihypertensive drugs, one, two, three (or more) drug combinations and fixed-dose combinations were received by 16.8%, 28.5%, 31.5% and 4.0% of patients, respectively. The most commonly used drug class was angiotensin-converting enzyme inhibitors (50%), followed by beta-blockers (42%) and diuretics (39%). Significant negative predictors of BP control included: body mass index ≥ 30 kg/m2, heart rate ≥ 70 bpm, history of hypertension ≥ 7 years, and kidney disease (the odds ratios adjusted by age and gender - 0.61; 0.76; 0.79; and 0.76, respectively). Conclusions: The percentage of Polish outpatients with adequate HT control is unsatisfactory. Patients with diabetes, chronic kidney disease, dyslipidaemia, overweight or obesity, longer disease and treatment duration and poor treatment compliance require a particularly careful assessment of risk factors and comorbidities, appropriate therapy intensification, and more frequent use of antihypertensive fixed-dose combinations.