Patient compliance in hypertension: role of illness perceptions and treatment beliefs.

Despite many years of study, questions remain about why patients do or do not take medicines and what can be done to change their behaviour. Hypertension is poorly controlled in the UK and poor compliance is one possible reason for this. Recent questionnaires based on the self-regulatory model have been successfully used to assess illness perceptions and beliefs about medicines. This study was designed to describe hypertensive patients' beliefs about their illness and medication using the self-regulatory model and investigate whether these beliefs influence compliance with antihypertensive medication. We recruited 514 patients from our secondary care population. These patients were asked to complete a questionnaire that included the Beliefs about Medicines and Illness Perception Questionnaires. A case note review was also undertaken. Analysis shows that patients who believe in the necessity of medication are more likely to be compliant (odds ratio (OR)) 3.06 (95% CI 1.74-5.38), P<0.001). Other important predictive factors in this population are age (OR 4.82 (2.85-8.15), P<0.001), emotional response to illness (OR 0.65 (0.47-0.90), P=0.01) and belief in personal ability to control illness (OR 0.59 (0.40-0.89), P=0.01). Beliefs about illness and about medicines are interconnected; aspects that are not directly related to compliance influence it indirectly. The self-regulatory model is useful in assessing patients health beliefs. Beliefs about specific medications and about hypertension are predictive of compliance. Information about health beliefs is important in achieving concordance and may be a target for intervention to improve compliance.