Purpose: The aim of our study was to evaluate the adherence to mineralocorticoid receptor (MR) antagonists and other antihypertensive therapy and blood pressure control in conservatively treated patients with primary aldosteronism (PA).
Materials and methods: Conservatively treated subjects with previously confirmed PA (n-50, 64.5 ± 9 years of age, 24% women) were investigated via our outpatient hypertension clinic. All subjects underwent regular examinations in our clinic. In addition to basic laboratory and clinical parameters, 24 h ambulatory blood pressure monitoring (ABPM) (Spacelabs) was evaluated. Unplanned blood sampling for assessment of serum antihypertensive drug concentrations by the means of liquid chromatography-mass spectrometry was performed in all patients. In case of spironolactone, its active metabolite canrenone was also evaluated. Total non-compliance was then defined as the absence of all measured antihypertensive drugs. Partial non-compliance was calculated as the absence of serum levels of at least one, but not all antihypertensive drugs prescribed.
Results: Good blood pressure control was detected (mean 24 h systolic/diastolic BP 130 ± 12/77 ± 9 mmHg). The average number of antihypertensive drugs was 3.9 ± 1.5. All subjects were treated by MR antagonists. 44% of patients received spironolactone (average daily dose 45 ± 20 mg) and in the remaining 56% of subjects eplerenone was administered (average daily dose 80 ± 30 mg) due to spironolactone side effects. Assessment of antihypertensive drug concentrations revealed full adherence in 80% of all subjects, partial nonadherence was noted in the remaining 20% of subjects. MR antagonist levels were detected in almost all subjects (49 out of 50).
Conclusions: Good blood pressure control and adherence to therapy were detected in conservatively treated patients with PA. Eplerenone had to be used quite often as male subjects did not tolerate dose escalation due to spironolactone side effects.
Keywords: Primary aldosteronism; adherence; antihypertensive treatment; blood pressure; chromatography–mass spectrometry.