Introduction: American Indians (AIs) have high rates of type 2 diabetes (T2D) and comorbidities. Mortality risk is increased by uncontrolled cardio-metabolic factors and significantly reduced by antihypertensive, glucose- and lipid-lowering medication adherence. Medication adherence is low among AIs living in non-Indian Health Services (IHS) healthcare settings, but little is known about medication adherence among AIs who primarily receive their medications from IHS/tribal facilities. The study aim was to identify cardio-metabolic control factors (hemoglobin A1c [HbA1c], low density lipoprotein [LDL-C], and systolic blood pressure [SBP]) and antihypertensive, glucose- and lipid-lowering medication adherence in adults with T2D who use Choctaw Nation of Oklahoma (CNO) Health Services.

Methods: Enrolled CNO tribal members with T2D over 18 years of age with at least one pharmacy visit and at least one HbA1c measure in 2017 (N=5,970, mean age 58.0±13.4, 52% female) were included in this descriptive pilot study. We used the earliest values of HbA1c, LDL-C and SBP in the measurement period. Medication adherence (proportion of days covered [PDC]) was calculated using 2017 CNO electronic health record (EHR) data. Medication classes included biguanides, statins, and ACE/ARBs.

Results: Fifty-six percent had HbA1c measurements above the target of 7%, 42% had LDL-C greater than 100mg/dL, and 63% had SBP above target of 130 mmHg. Thirty-six percent had both HbA1c and SBP levels above target. The percentage of patients with PDC ≥.80 was 63% for biguanides, 66% for statins, and 70% for ACE/ARBs.

Discussion/Conclusions: Previous studies have reported similar findings for cardio-metabolic control factors as well as higher medication adherence rates. Future studies should focus on examining prescription and pharmacy refill data longitudinally and should include a subgroup of patients to understand facilitators of and barriers to medication adherence not available within EHR data.


T.N. Nelson: None. Y. Yao: None. A. DeVaughan-Circles: None. D.J. Wilkie: Other Relationship; eNursing llc. L. Scarton: None.

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