Evidence map›Paper›PMID 41558762›Full record

ArticleBMJ open diabetes research & care2026

Zero Dollar Drug Copay program improves antidiabetic medication adherence and medication use patterns among Blue Cross and Blue Shield of Louisiana members with diabetes in Louisiana.

Tiange Tang, Charles Stoecker, Debra Winberg, Mingyan Cong, Miao Liu, Elizabeth Nauman, Yun Shen, Gang Hu, Hui Shao, Jian Li and 6 more

Abstract read
In one paragraph

Article in BMJ open diabetes research & care, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
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1 · What the graph read from it

What it found

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2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

16 authors.

Tiange TangHealth Management and Policy, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana, USA.ORCID http://orcid.org/0000-0001-6896-4576
Charles StoeckerHealth Management and Policy, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana, USA.
Debra WinbergHealth Management and Policy, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana, USA.ORCID http://orcid.org/0000-0003-2909-1455
Mingyan CongBlue Cross and Blue Shield of Louisiana, Baton Rouge, Louisiana, USA.
Miao LiuBlue Cross and Blue Shield of Louisiana, Baton Rouge, Louisiana, USA.
Elizabeth NaumanLouisiana Public Health Institute, New Orleans, Louisiana, USA.
Yun ShenLSU Pennington Biomedical Research Center, Baton Rouge, Louisiana, USA.
Gang HuLSU Pennington Biomedical Research Center, Baton Rouge, Louisiana, USA.ORCID http://orcid.org/0000-0002-6172-8017
Hui ShaoHubert Department of Global Health, Rollins School of Public Health, Atlanta, Georgia, USA.ORCID http://orcid.org/0000-0002-4088-546X
Jian LiHealth Management and Policy, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana, USA.
Alessandra N BazzanoUNC-Chapel Hill, Chapel Hill, North Carolina, USA.
Eboni Price-HaywoodOchsner Health System, New Orleans, Louisiana, USA.ORCID http://orcid.org/0000-0003-2901-3852
Brice Labruzzo MohundroBlue Cross and Blue Shield of Louisiana, Baton Rouge, Louisiana, USA.
Jason OuyangBlue Cross and Blue Shield of Louisiana, Baton Rouge, Louisiana, USA.
Mollie CarbyBlue Cross and Blue Shield of Louisiana, Baton Rouge, Louisiana, USA.
Lizheng ShiHealth Management and Policy, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana, USA lshi1@tulane.edu.

Funding

Tracking & Evaluation CoreU54GM104940 · NIGMS · LSU PENNINGTON BIOMEDICAL RESEARCH CTR · PI Peter Todd Katzmarzyk · 2012 to 2026
$69.1M
NCCDPHP CDC HHS U18 DP006523NIGMS NIH HHS U54 GM104940
6 · The paper itself

Abstract

objectiveBlue Cross and Blue Shield of Louisiana (BCBSLA) launched a zero-dollar co-pay (ZDC) pharmacy benefit on July 1, 2020, to reduce cost-related barriers to diabetes medications. This study evaluated the program's effect on antidiabetic medication adherence and use patterns. RESEARCH DESIGN AND

methodsWe conducted a retrospective cohort study using BCBSLA medical and pharmacy claims from 2019-2021. The study included 7,603 continuously enrolled members with diabetes: 3,045 fully insured members with ZDC coverage (ZDC group) and 4,558 administrative-services-only members without ZDC coverage (control group). Follow-up was July 1, 2020, to December 31, 2021. Outcomes included monthly proportion of days covered (PDC), drug counts, and monthly medication use. We applied propensity score odds weights and estimated weighted difference-in-differences models with individual and time fixed effects, adjusting for demographics, comorbidities, healthcare utilization, and spending. Subgroup analyses examined pre-ZDC users, pre-ZDC non-users, and complex users.

resultsMean age was 48.8 (SD 12.5) years in the ZDC group and 52.9 (SD 11.3) years in controls; 57.4% and 55.6% were female, respectively. The ZDC program increased PDC by 4.4 percentage points (p<0.001), monthly medication use by 6.2 percentage points (p<0.001), and drug counts by 0.090 (p<0.001). For ZDC-eligible medications, increases were 5.4 percentage points for PDC, 7.6 percentage points for monthly use, and 0.074 for drug counts (all p<0.001). Improvements were observed among pre-ZDC users and complex users, but not among pre-ZDC non-users.

conclusionA zero-dollar co-pay pharmacy benefit improved antidiabetic medication adherence and increased medication use among BCBSLA members with diabetes.

Indexed as

Blue Cross Blue Shield Insurance PlansDiabetes MellitusDrug MonitoringHypoglycemic AgentsAdherence InterventionsFemaleFollow-Up StudiesHumansLouisianaMaleMiddle AgedPrognosisRetrospective StudiesHypoglycemic AgentsMedication AdherenceProgram Evaluation

Identifiers

PMID41558762
PMCPMC12820829

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.