Nonadherence to angiotensin-converting enzyme inhibitors and/or angiotensin II receptor blockers among high-risk patients with diabetes in Medicare Part D programs.
OBJECTIVE
To identify predictors of nonadherence to angiotensin-converting enzyme inhibitors (ACEIs) and/or angiotensin II receptor blockers (ARBs) and to assess the association between nonadherence to ACEIs/ARBs and potentially avoidable hospitalizations (PAHs) among elderly high-risk patients with diabetes.


METHODS
Medicare Part D enrollees from six states who had diabetes and coexisting hypertension and/or renal disease, were aged 65 years or older, and who had filled at least one prescription for ACEIs/ARBs in the first 6 months of 2006 were included in this retrospective cohort study. The primary outcomes of interests were patient nonadherence to ACEI/ARB therapy, which was defined as a proportion of days covered (PDC) less than 0.8 and PAH for diabetes during the patient follow-up period (July 1, 2006, to March 31, 2007).


RESULTS
A total of 599,141 patients (mean [+/-SD] age 75.6 +/-7.3 years, 66% women, 63% white, 15% black, and 9% Hispanic) were included. Among them, 46% were nonadherent to ACEI/ARB therapy and 6.3% had a PAH during the follow-up period. In multivariate logistic regressions, patients with diabetes and both hypertension and renal disease and patients with diabetes and renal disease only were 24% and 15% more likely, respectively, to be nonadherent to ACEI/ARB therapy compared with patients with diabetes and hypertension. Black and Hispanic patients were also more likely to be nonadherent to ACEI/ARB therapy. Nonadherence to ACEI/ARB therapy was associated with a 5% increase in the likelihood of PAH.


CONCLUSIONS
Adherence to ACEI/ARB therapy is suboptimal among elderly high-risk patients with diabetes enrolled in Medicare Part D programs from six states, and nonadherence to ACEIs/ARBs is associated with a slightly increased risk for PAH.
Yang
Yi
Y
School of Pharmacy, University of Mississippi, University, MS 38677, USA. yiyang@olemiss.edu
Thumula
Vennela
V
Pace
Patrick F
PF
Banahan
Benjamin F
BF
Wilkin
Noel E
NE
Lobb
William B
WB
D000368:Aged; D000369:Aged, 80 and over; D047228:Angiotensin II Type 1 Receptor Blockers / Q000627:therapeutic use*; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use*; D000959:Antihypertensive Agents / Q000627:therapeutic use; D048909:Diabetes Complications; D004359:Drug Therapy, Combination; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D006973:Hypertension / Q000150:complications* / Q000188:drug therapy*; D008297:Male; D054524:Medicare Part D; D014481:United States; D016903:Drug Monitoring
D047228:Angiotensin II Type 1 Receptor Blockers; D000806:Angiotensin-Converting Enzyme Inhibitors; D000959:Antihypertensive Agents