Background: Poor adherence is thought to be one of the major common causes of uncontrolled high blood
pressure over the world leading to useless drug dose or class changes which may lead to increased adverse effects and
medical costs. The current study aimed to investigate the relationship between knowledge about complications related to
hypertension and adherence to antihypertensive treatment.
Materials and Methods: A cross-sectional study was carried out between May and November 2013 on a representative
sample of 453 hypertensive patients at public primary care outpatients in the department of Tlemcen in Algeria. The
adherence was assessed with the adherence evaluation scale of Girerd which contains six items with closed dichotomous
responses (yes/no). The degree of adherence was calculated according to the score resulting from the sum of all "yes"
answers. A cut-off value of 80% was used to categorize patients as "adherent" or "non-adherent". To do so, a structured
questionnaire has been performed including patients’ knowledge about hypertension complications and the other factors
which may affect adherence therapy.
Results: Among the 453 patients included in the study, only 35.5% were adherents. Univariate analysis has shown a
positive relationship between knowledge about hypertension complications and adherence. However, comorbidities, and
number of antihypertensive drugs prescribed, were associated with poor adherence. In a multivariate analysis, a
significant difference was shown between adherents and non-adherents according to the factors mentioned above and the
Conclusion: This study has shown a positive relationship between patients’ knowledge about the hypertensive
complications and adherence. In contrast, increased number of antihypertensive drugs taken May affect negatively the
adherence to therapy.