Invited review
Compliance with treatment in hypertension

Among the several factors responsible for suboptimal control rates in hypertension, patient adherence, i.e. patient compliance, and persistence have been identified as two of the main causes. Patient compliance, or synonymously, patient adherence, is the extent to which a person’s behavior – taking medication, following a diet, and/or executing lifestyle changes, corresponds with agreed recommendations from a healthcare provider, whereas medication persistence represents the accumulation of time from initiation to discontinuation of therapy. Persistence is measured in terms of time, whereas medication adherence is reported in terms of the percentage of prescribed doses taken per defined period of time. When monitored electronically, patients have been shown to be fully compliant (50-60% of total), i.e. those who follow at least 80% of the prescribed regimen; partially compliant (30-40% of total), i.e. patients with periods of poor adherence or “drug holidays”; or non-compliant (5-10% of total), i.e. those with levels of compliance less than 80% of the prescribed treatment. Compliance is a multidimensional phenomenon determined by the interplay of five sets of factors: patient related, condition related, therapy related, health system related, and social/economic related. Compliance is assessed by electronic monitoring devices, pharmacy refill rates, pill counts, and pharmacological methods. Compliance can be improved by patient education, simplifying the dosage regimen, selecting drugs that are well tolerated, patient self-monitoring, involving family members, electronic pill cap monitors, “alarm clocks”, computer based reminder systems, and remote home monitoring systems.