Medication adherence and associated hemoglobin A1c in type 2 diabetes.
BACKGROUND
Tight blood glucose control has been correlated with a reduction in diabetes complications. Adherence to antidiabetic medications is crucial to achieving blood glucose control.


OBJECTIVE
To assess the relationship between good glucose control [glycosylated hemoglobin (HbA1c) levels] and adherence to prescribed treatment in patients on a stable medication regimen for type 2 diabetes.


METHODS
The Morisky survey, a 4-item questionnaire that predicts patient medication-taking behavior, was used to assess adherence in 301 patients. The relationship of HbA1c to Morisky score was evaluated, controlling for other variables related to patient demographics and clinical characteristics. Data were analyzed using a general linear model on log (HbA1c).


RESULTS
Unadjusted mean HbA1c values (capped at 14.0%) for patients with Morisky scores of 0 or 1, 2, 3, and 4 were 8.92%, 8.67%, 7.74%, and 7.60%, respectively. Of all patients, 13.0%, 14.0%, 24.3%, and 48.8% had scores of 0 or 1, 2, 3, and 4, respectively. Good adherence (Morisky score > or = 3) was associated with a 10% lower total HbA1c (p = 0.0003) adjusted for all other factors in the model. Duration of diabetes (5-10 y) and presence of diabetes complications were also significantly associated with HbA1c (p = 0.026 and 0.002, respectively). Adherence was poor in 27% of patients.


CONCLUSIONS
This study found that patients with a higher score on the Morisky scale had a lower associated HbA1c measurement. The Morisky score may be an efficient tool for identifying patients with poor medication-taking behavior who can then be targeted for directed adherence counseling services.
Krapek
Kimberley
K
Diabetes Solutions, Aurora, CO, USA.
King
Kathleen
K
Warren
Susan S
SS
George
Karen G
KG
Caputo
Dorothy A
DA
Mihelich
Karen
K
Holst
Elizabeth M
EM
Nichol
Michael B
MB
Shi
Sheng G
SG
Livengood
Kevin B
KB
Walden
Steve
S
Lubowski
Teresa J
TJ
D000293:Adolescent; D000328:Adult; D000368:Aged; D001786:Blood Glucose / Q000032:analysis; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000188:drug therapy*; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis*; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D007328:Insulin / Q000627:therapeutic use; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D010349:Patient Compliance / Q000706:statistics & numerical data*; D010353:Patient Education as Topic; D011795:Surveys and Questionnaires
D001786:Blood Glucose; D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D007328:Insulin