Antihypertensive medication adherence in chronic type B aortic dissection is an important consideration in the management debate

Objective: Early aortic stenting in chronic type B aortic dissection (TBAD) may lead to long-term benefit, although the optimal treatment strategy is hotly debated. A robust comparison to outcomes seen in medically managed patients is challenging as the rate of antihypertensive medication adherence is unknown. The aims of this study were therefore to identify the rate of antihypertensive medication adherence and predictors of adherence in TBAD. Methods: This was a cross-sectional mixed methods study of patients with TBAD. Medication adherence was assessed by the eight-item Morisky Medication Adherence Scale together with an assessment of demographic, behavioral, and psychological variables and disease-specific knowledge. Results: There were 47 patients (mean age, 59 years; 81% male) who were recruited from a tertiary vascular unit. The mean total number of medications taken was 5.8 (2-14), and the mean number of antihypertensive medications was 1.9 (1-6). Of the 47 patients, 20 (43%) reported high levels of medication adherence, 17 (36%) reported moderate adherence, and 10 (21%) reported low adherence. Previous aortic surgery was associated with higher levels of adherence (beta = 0.332; P =.03), as was taking a greater number of medications (beta = 0.332; P =.026), perceived benefit from treatment (beta = 0.486; P <.001), good memory (beta = 0.579; P <.001), and low fears of side effects (beta = 0.272; P <.014). Conclusions: Medical management remains the mainstay of treatment in uncomplicated TBAD; however, the majority of patients are poorly adherent to their antihypertensive medications. The merits of thoracic endovascular aortic repair in TBAD are argued, and poor adherence is an important factor in the debate; one cannot robustly compare two strategies when half of a treatment group may not be receiving the stated intervention. To develop an evidence-based treatment strategy for TBAD, we must take into account the direct and indirect effects of medical therapy and thoracic endovascular aortic repair. Further work to improve medication adherence and to understand its impact on disease progression is vital to inform the debate and to deliver the best outcomes for patients.