Electronic monitoring of adherence as a tool to improve blood pressure control. A randomized controlled trial.

BACKGROUND Poor adherence to antihypertensive drug regimens is believed to be a major contributor to treatment failure. Electronic monitoring of adherence may improve adherence and allow differentiation between those who are nonadherent and those who are pharmacologically nonresponsive. This study was designed to evaluate the effectiveness of electronic monitoring of adherence in lowering blood pressure (BP) in comparison with usual care. METHODS A total of 258 patients with high BP despite use of antihypertensive medication were randomly assigned to either continuation of usual care (with adjustment in antihypertensive medication if necessary) or to the introduction of electronic monitoring. Adherence to antihypertensive medication was monitored for 2 months without medication changes. The primary outcome measure was the proportion of patients who reached target BP levels after a 5-month follow-up period. RESULTS At 5 months, 50.6% of the patients in the usual care group reached adequate BP, v 53.7% in the electronic monitoring group (P = .73). The percentages of patients with drug additions or increases in dosage were higher in the usual care group compared with those in whom adherence was monitored (P < .01). CONCLUSION These data show that electronic monitoring in comparison to usual care results in similar BP control but leads to fewer drug changes and less drug use. This result is likely to be achieved by improving adherence. Hence a strategy that includes electronic monitoring has the potential to prevent unnecessary treatment escalation in patients with poor adherence.