Integrated Specialty Pharmacy Care and PAH Drug Adherence

Integrating pharmacists into specialty care proves its many benefits.

Integrated pharmacy practice models have been associated with improved management of diseases including high cholesterol, multiple sclerosis and hematologic malignancies. In these cases, integration of specialty pharmacists into clinical care teams improved patients’ medication adherence, drug education, and on-going monitoring, as well as reducing costs.

In a new study of integrated specialty pharmacy care for patients with pulmonary arterial hypertension (PAH), investigators at Vanderbilt University Medical Center found that patients realize many of these same benefits reported with other diseases.

“Patients, providers and clinic staff noted an improvement in coordination and quality of care.”

“In 2014, Vanderbilt Specialty Pharmacy (VSP) collaborated with the outpatient pulmonary clinic to incorporate a pharmacist and pharmacy technician as patient care partners. Following integration, patients, providers and clinic staff noted an improvement in coordination and quality of care. It was important for our team to quantify these benefits to better understand the impact of our service model,” said Nisha B. Shah, Pharm.D., a research pharmacist with VSP. Shah was lead author on the study, reported in PLOS One.

Sub-optimal Medication Adherence

Phosphodiesterase-5 (PDE-5) inhibitors, commonly sildenafil or tadalafil, can improve disease symptoms and quality of life for patients with PAH when taken consistently. However, adherence to these medications is far less than optimal. One study found fewer than half of patients with PAH prescribed PDE-5 inhibitor therapy were adherent at six months.

Elsewhere, researchers have suggested several factors that may influence medication adherence, including hospitalization, adverse events (AEs), out-of-pocket costs and frequency of dosing.

Testing the Integrated Model

VSP conducted a retrospective study of adult patients with PAH treated at Vanderbilt’s outpatient pulmonary clinic from January 2014 through December 2016, the first two-year period of the clinic’s integrated model. All 131 patients in the study received PDE-5 inhibitor therapy (sildenafil and/or tadalafil).

Overall, patients receiving care within the integrated pharmacy model achieved high medication adherence. The overall average proportion of days covered (PDC) was 96 percent, with 94 percent of patients achieving optimal adherence of ≥ 80 percent PDC. Also significant, previously identified predictors of low adherence including hospitalizations, out-of-pocket drug cost and dosing frequency did not negatively impact adherence within this high-touch model.

Nearly half (47 percent) of patients experienced an AE during the study period, which affected adherence. Patients reporting an AE were 4.2 times more likely to be non-adherent to PDE-5 inhibitor therapy. The most common AE was headache (24 percent of all patients reported headache).

Building on Success

Vanderbilt’s integrated specialty pharmacy model was first introduced in 2011 and has since expanded to 23 specialty clinics. As part of a multidisciplinary team, pharmacists and technicians assist patients in the clinics with a range of concerns, including on-going monitoring, medication education and medication access, as well as affordability.

“In our model, medication renewals are not auto-filled… providing a recurring opportunity to engage with patients.”

“There are many ways that an integrated pharmacy model can improve patient outcomes,” Shah said. “For example, in our model, medication renewals are not auto-filled. A pharmacist or pharmacy technician speaks with patients on a monthly basis, providing a recurring opportunity to engage with patients about ongoing appropriateness and safety of therapy, resolve their questions, and mitigate access barriers.”

For patients with PAH, Shah says their data only confirmed the tangible benefits seen in the pulmonary clinic. “Our integration into the pulmonary clinic has reduced provider and clinic staff burden. From ensuring patients are able to start and stay on treatment to monitoring for safety and effectiveness, our pharmacists have become essential to the care team.”