Masked uncontrolled hypertension not attributable to medication nonadherence
Poor adherence to blood pressure (BP)-lowering medications does not appear to be a cause of masked uncontrolled hypertension (MUCH), with a recent study showing that the levels of medication adherence is similar between patients with MUCH and those with true controlled hypertension.
The study included 167 individuals with controlled office BP and adequate 24-hour ambulatory BP recordings. Of these patients, 86 were controlled by in-clinic BP assessment (<135/85 mm Hg) but had uncontrolled ambulatory awake BP (daytime readings ≥135/85 mm Hg or 24-hour readings ≥130/80 mm Hg), indicative of MUCH. The remaining 81 had controlled in-clinic and ambulatory awake BP, consistent with true controlled hypertension.
After excluding nine individuals with missing medication adherence data, the final analysis included 81 patients in the MUCH group (mean age, 58.6 years; 44.4 percent female) and 77 in the true controlled hypertension group (mean age, 60.6 years; 45.5 percent female). The mean body mass index was not statistically different in both groups, but MUCH patients had a higher prevalence of diabetes (42.0 percent vs 23.4 percent; p=0.013).
In the MUCH group, 69 patients (85.2 percent) were fully adherent to their medications and 12 (14.8 percent) were partially adherent (fewer medications detected than prescribed). The corresponding numbers of patients in the true controlled hypertension group were 69 (89.6 percent) and eight (10.4 percent). Neither complete nor partial adherence significantly differed between the two groups (p=0.403). None of the patients in entire cohort showed complete nonadherence.
Results for urinary drug and drug metabolite levels showed comparably high levels of antihypertensive medication adherence in both MUCH and truly controlled hypertensive patients, suggesting that MUCH is not attributable to antihypertensive medication nonadherence.