Background: HbA1c is a primary measure of glycemic control and managing HbA1c may help reduce the risk of complications. This study aimed to describe trends in HbA1c by insulin regimen.

Methods: This was a retrospective analysis of cross-sectional surveys collected from the National Health and Nutrition Examination Survey between 2009-2018. Mean HbA1c and proportion achieving guideline- and HCP-recommended (i.e. personalized) HbA1c targets were evaluated in aggregate and over time in adults (18-64 years) with type 1 (T1DM) or type 2 (T2DM) diabetes using mealtime insulin (MTI) or basal insulin only. Trends over time between 2009-2018 were evaluated after adjusting for age, gender, race/ethnicity. The analysis included the strata, clusters, and weighting of the complex survey design.

Results: From 2009-2018, 26.1% of people with T1DM (weighted n=891,194; mean HbA1c [SE] 7.9% [0.2]) , 24.8% with T2DM MTI (weighted n=1,591,183; mean HbA1c [SE] 8.6% [0.2]) , and 11.2% with T2DM basal only (weighted n=1,087,895; mean HbA1c [SE] 8.6% [0.2]) achieved the ADA recommended HbA1c goal of <7%. Among those who reported personalized HbA1c goals, 28.7% (T1DM) , 9.5% (T2DM MTI) , and 17.1% (T2DM basal only) achieved their goals. After adjustment, the proportion of people achieving HbA1c <7% in the basal only group increased significantly over time (2009-2018; p=0.04) , driven by an increase in 2017-2018. Adjusted mean HbA1c for T2DM MTI significantly decreased during the 2009-2018 timeframe (p=0.003) , whereas no significant differences were seen in the other subgroups.

Conclusions: Across all insulin regimens based off the most recent NHANES data, ∼75-90% of individuals are not achieving ADA-recommended or personalized HbA1c goals. Emerging treatment tools (e.g. new technologies, advanced insulins, and time in range metrics) may facilitate improved diabetes outcomes.


E.R.Hankosky: Employee; Eli Lilly and Company, Stock/Shareholder; Eli Lilly and Company. D.Schapiro: Employee; Eli Lilly and Company. K.B.Gunn: Employee; Eli Lilly and Company. E.Lubelczyk: Employee; Eli Lilly and Company. J.Mitroi: None. D.R.Nelson: Employee; Eli Lilly and Company.


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