Effect of a clinical pharmacist-managed service on blood pressure in an underserved population with resistant hypertension

Purpose: To determine if a clinical pharmacist-managed resistant hypertension service has an effect on blood pressure (BP) in an underserved population.

Methods: This ongoing prospective, observational cohort study is evaluating patients enrolled in a pharmacist-managed resistant hypertension service with at least one post-enrollment encounter.  BP is measured in clinic and at home (monitors provided).  Patients enrolled in the service are followed at two week intervals alternating telephone and clinic encounters.  The primary outcome is mean change in home systolic blood pressure (SBP).  Secondary outcomes include change in home diastolic blood pressure (DBP), clinic BP, and BP from initial encounter to end of study.  Last observation is carried forward.

Results: Eight patients are included in this interim analysis over a mean duration of 54 + 24 days.  Baseline characteristics (mean + SD) include age 56 (+8) years, BMI 40 kg/m2 (+8), clinic SBP 155 mm Hg (+8), DBP 83 mm Hg (+11), treatment  including 4.25 (+1.2) anti-hypertensives, 87.5% African American, 12.5% Caucasian, 88% with diabetes mellitus, and 25% with chronic kidney disease.  The primary outcome of change in home SBP was -13 mm Hg (+18), p=0.099.  Change in clinic SBP was -9 mm Hg (+15), p=0.13.  Clinic BP goal has been achieved in 12.5% of participants and home BP goal has been achieved in 28.6%.  Change in initial clinic SBP to end of study home SBP was -25 mm Hg (+15), p=0.005.

Conclusion: A reduction in home SBP was observed in the pharmacist-managed service, but the change did not reach statistical significance.  The study is ongoing and statistical power has not been met.  Fifteen subjects are needed to meet power and it is fully anticipated that the project will be completed by the time of presentation.