Medication non-compliance is identified as a major public health concern and leads to considerable morbidity, mortality and healthcare costs. This study was aimed to identify factors associated to patients’ non-compliance with antihypertensive treatment.Design and method:
A cross-sectional study was conducted with administrative databases (2012) of the third Belgian health insurer (Mutualités Libres - Onafhankelijke Ziekenfondsen) that covers about 2 million individuals including 16% of hypertensive patients. Non-compliance was measured using the medication possession ratio (MPR less than 80%). A multivariate logistic regression was employed to determine risk factors for non-compliance with antihypertensive medications, with a significance level of 5%.Results:
The rate of non-compliance to antihypertensive medications was 26.7% in the study population. A significant association has been found between non-compliance to treatment and younger and advanced age groups (adjusted odds ratio [OR] = 2.26 for 18–24, [OR] = 1.33 for 25–49, [OR] = 1.22 for 75 or older, compared to 50–74), female sex (OR = 1.19), single persons (OR = 1.10), number of comorbidity (OR = 1.15 for 1 or 2 comorbidities, OR = 1.33 for more than 2 comorbidities), patient cost for all medications (OR = 1.05 for 100–199 euros, OR = 1.19 for more than 199 euros), some antihypertensive drug classes (OR = 4.1 for beta-blockers and association, OR = 0.56 for calcium channel blockers, OR = 0.20 for angiotensin converting enzyme and angiotensin receptor blockers and association, compared to diuretics).Conclusions:
Despite the proven efficacy of antihypertensive treatment in preventing cardiovascular morbidity in clinical trials, our study showed a high rate of non-compliance. The association between non-compliance and the number of comorbidity, the cost for medications, some antihypertensive drug classes suggests that patient on poly-medication, lack of finances and side effects of medications (notably beta-blockers) are significant risk factors for non-compliance. Therefore, it is essential to pay particular attention to these factors to enhance medication compliance and to ultimately impact positively on cardiovascular outcome.