PLASMA BETA BLOCKER LEVEL MEASUREMENT - THE DIFFERENCE IN TREATMENT ADHERENCE ACCORDING TO TYPE OF BETA BLOCKER

Objective: Beta-blocker treatment is commonly used in patients with arterial hypertension. Patients treated with more selective beta-blocker are believed to experience less frequently adverse effects of the drug. Suboptimal medication adherence is common in patients treated with beta-blocker, but there is little evidence about comparing the adherence between different beta blockers. The aim of our study was to evaluate non adherence rate among the patients taking beta-blockers for the treatment of arterial hypertension and to compare the adherence to different types of beta-blockers.Design and method: We analyzed 421 serum beta blocker levels in 261 patients. Minimal time interval between the two measurements was three months. We analyzed “first measurement” within the single patient (n = 261) and also repeated measurements in patients with more than one plasma level sample (“all measurements”, n = 421). Non-adherence to betaxolol, bisoprolol, metoprolol and nebivolol was analyzed separately and compared. Results: Non-ahrerence to beta-blocker based on the results of the “first measurement within the patient” was 25,30 % and based on the results of the “all measurement” was 23,3%. 46,3% patients varied in non-adherence status among 70 patients with two or more measurement available, 53,7% of patients were adherent or non-adherent in all measurements. The highest rate of non-adherence was in patients prescribed with nebivolol (30,9%), the lowest in patients prescribed with betaxolol (15,9%), p < 0,269. Non-adherence to treatment was most common in nebivolol also in “all measurements” (33,7%) and lowest in betaxolol (8,9%), p < 0,001. Association between adherence to the treatment and number of used antihypertensive drugs was not statistically significant (p = 0,416). Conclusions: Non-adherence to beta-blocker treatment in patients with arterial hypertension was lower than expected and is not equal in different types of beta-blockers. Adherence does not correlate with beta-1 selectivity of the beta-blocker. The variability of adherence is high among patients with repeated testing.