An Evaluation of a Clinical Pharmacy-Directed Intervention on Blood Pressure Control

OBJECTIVE To compare short and long term blood pressure control with clinical pharmacy specialist involvement to traditional physician management. SETTING A non-profit health maintenance organization in the United States covering approximately 385,000 lives. METHODS This analysis utilized a prospective parallel design. Adult patients with a baseline Blood pressure>140/90 mmHg and receiving at least one antihypertensive medication were eligible for the study. Eligible hypertension management patients at one medical office were referred to the office's clinical pharmacy specialist (intervention cohort) while at another comparable medical office they received usual physician-directed care (control cohort). The primary outcome measure was achievement of a goal BP (<140/90 mmHg) during a six month follow-up. Medical records were also reviewed approximately 1.5 years post enrollment to assess long-term BP control after clinical pharmacy-managed patients returned to usual care. Multivariate analyses were performed to adjust for baseline cohort differences. RESULTS One hundred-thirteen and 111 subjects in the intervention and control cohorts completed the study, respectively. At the end of the follow-up period, clinical pharmacy-managed subjects were more likely to have achieved goal BP (64.6%) and received a thiazide diuretic (68.1%) compared to control subjects (40.7% and 33.3%, respectively) (adjusted p=0.002 and p<0.001, respectively). The proportion of clinical pharmacy-managed subjects with controlled BP decreased to 22.2% after returning to usual care (p<0.001). CONCLUSION Clinical pharmacy involvement in hypertension management resulted in increased BP control. Loss of long-term control after discontinuation of clinical pharmacy management supports a change in care processes that prevent patients from being lost to follow-up.