Open Access Research article

Does the presence of a pharmacist in primary care clinics improve diabetes medication adherence?

Beverly Mielke Kocarnik1, Chuan-Fen Liu23, Edwin S Wong23*, Mark Perkins2, Matthew L Maciejewski45, Elizabeth M Yano67, David H Au28, John D Piette109 and Chris L Bryson12

Author Affiliations

1 Division of General Internal Medicine, University of Washington, 329 Ninth Ave, Campus Box 359780, Seattle, WA, 98104, USA

2 Northwest Center for Outcomes Research in Older Adults, VA Puget Sound Health Care System, 1100 Olive Way, Suite 1400, Seattle, WA, 98101, USA

3 Department of Health Services, University of Washington, Box 357660, Seattle, WA, 98195, USA

4 Center for Health Services Research in Primary Care, Durham VA Medical Center, 508 Fulton St, Durham, NC, 27705, USA

5 Division of General Internal Medicine, Duke University Medical Center, 2301 Erwin Rd, Durham, NC, 27710, USA

6 Center for the Study of Healthcare Provider Behavior, Los Angeles VA 16111 Plummer St (152), Los Angeles, CA, 91343, USA

7 Department of Health Services, University of California, 650 Charles Young Dr. S. 31-269 CHS, Box 951772, Los Angeles, CA, 90095, USA

8 Department of Medicine, University of Washington, RR-512 Health Sciences, Box 356420, Seattle, WA, 98195, USA

9 VA Center for Clinical Management Research, VA Ann Arbor Healthcare System, 2215 Fuller Rd., Mail Stop 152, Ann Arbor, MI, 48105, USA

10 Department of Internal Medicine, University of Michigan School of Medicine, 1500 E. Medical Center Drive, Ann Arbor, MI, 48109, USA

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BMC Health Services Research 2012, 12:391  doi:10.1186/1472-6963-12-391

Published: 13 November 2012



Although oral hypoglycemic agents (OHAs) are an essential element of therapy for the management of type 2 diabetes, OHA adherence is often suboptimal. Pharmacists are increasingly being integrated into primary care as part of the move towards a patient-centered medical home and may have a positive influence on medication use. We examined whether the presence of pharmacists in primary care clinics was associated with higher OHA adherence.


This retrospective cohort study analyzed 280,603 diabetes patients in 196 primary care clinics within the Veterans Affairs healthcare system. Pharmacists presence, number of pharmacist full-time equivalents (FTEs), and the degree to which pharmacy services are perceived as a bottleneck in each clinic were obtained from the 2007 VA Clinical Practice Organizational Survey—Primary Care Director Module. Patient-level adherence to OHAs using medication possession ratios (MPRs) were constructed using refill data from administrative pharmacy databases after adjusting for patient characteristics. Clinic-level OHA adherence was measured as the proportion of patients with MPR >= 80%. We analyzed associations between pharmacy measures and clinic-level adherence using linear regression.


We found no significant association between pharmacist presence and clinic-level OHA adherence. However, adherence was lower in clinics where pharmacy services were perceived as a bottleneck.


Pharmacist presence, regardless of the amount of FTE, was not associated with OHA medication adherence in primary care clinics. The exact role of pharmacists in clinics needs closer examination in order to determine how to most effectively use these resources to improve patient-centered outcomes including medication adherence.

Pharmacist; Medication adherence; Diabetes mellitus; Oral hypoglycemic agent; Patient-centered medical home