OBJECTIVES: The American Diabetes Association recommends a HbA1c target of 7% for most adults, while the Healthcare Effectiveness Data and Information Set (HEDIS) defines poor control as HbA1c > 9%. This study examines the relationship between HbA1c reduction and medical costs among patients with type 2 diabetes (T2D).

METHODS: The Truven MarketScan^® databases (2013Q1 - 2017Q4) were utilized to identify patients with T2D and a HbA1c result from 2013Q3 through 2016Q4, with first such date identified as the index date. Patients were excluded if they were < 18, pregnant, did not have a HbA1c result in the first-year post index date, or did not have insurance coverage from 6 months prior through 2 years post index date. General linear models examined the relationship between HbA1c and all-cause and diabetes-related medical costs, controlling for patient characteristics, general health, comorbidities, medication use, resource use and index HbA1c.

RESULTS: Multivariable analyses (N=79,393) revealed that all-cause total medical costs in the 2 years post index were significantly lower for patients with an index HbA1c < 7% or ≤ 9%, compared to patients with an index HbA1c ≥ 7% or > 9% ($27,197 v $29,093; $27,861 v $29,262; both P<0.0001). Similarly, diabetes-related costs were significantly lower for patients with an index HbA1c < 7% or ≤ 9%, compared to ≥ 7% or > 9% ($7,610 v $14,031; $9,178 v $18,923; both P<0.0001). Among patients with index HbA1c ≥ 7% (N=35,814) or > 9% (N=10,824), a 1% reduction in HbA1c was associated with a 3.9% or 1.5% reduction in all-cause total costs and a 7.7% or 2.5% reduction in diabetes-related total costs, respectively (all P<0.05).

CONCLUSIONS: Higher index HbA1c was associated with significantly higher all-cause and diabetes-related costs. Furthermore, for patients with index HbA1c above recommended target, there are significant economic benefits associated with reducing HbA1c.