Adherence and medication belief in patients with pulmonary arterial hypertension or chronic thromboembolic pulmonary hypertension: A nationwide population-based cohort survey.
BACKGROUND
Pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) are rare diseases with a gradual decline in physical health. Adherence to treatment is crucial in these very symptomatic and life threatening diseases.


OBJECTIVE
To describe PAH and CTEPH patients experience of their self-reported medication adherence, beliefs about medicines and information about treatment.


METHODS
A quantitative, descriptive, national cohort survey that included adult patients from all PAH-centres in Sweden. All patients received questionnaires by mail: The Morisky Medication Adherence Scale (MMAS-8) assesses treatment-related attitudes and behaviour problems, the Beliefs about Medicines Questionnaire-Specific scale (BMQ-S) assesses the patient's perception of drug intake and the QLQ-INFO25 multi-item scale about medical treatment information.


RESULTS
The response rate was 74% (n = 325), mean age 66 ± 14 years, 58% were female and 69% were diagnosed with PAH and 31% with CTEPH. Time from diagnosis was 4.7 ± 4.2 years. More than half of the patients (57%) reported a high level of adherence. There was no difference in the patients' beliefs of the necessity of the medications to control their illness when comparing those with high, medium or low adherence. Despite high satisfaction with the information, concerns about potential adverse effects of taking the medication were significantly related to adherence.


CONCLUSIONS
Treatment adherence is relatively high but still needs improvement. The multi-disciplinary PAH team should, together with the patient, seek strategies to improve adherence and prevent concern.