Introduction: Insulin remains a last line therapy for type 2 diabetes, and formulations have improved significantly over the past 30 years. It is unknown whether these advancements have translated into better glycemic control in persons with diabetes.

Methods: We conducted a trends analysis of cross-sectional data from the National Health and Nutrition Examination Survey (NHANES, 1988-2020) . Our analysis included 8,658 nonpregnant adults aged ≥20 with diagnosed diabetes. We examined trends in self-reported diabetes medication use (insulin or oral) and glycemic control (A1c<7.0%) , overall and by race/ethnicity.

Results: From 1988-1994 to 2013-2020, there was an increase in the proportion of US adults with diabetes using only oral glucose-lowering medications (43.5% to 55.2%, p=0.003) . The proportion of patients using insulin did not change over the same period (30.5% to 28.2%, p=0.81) . Glycemic control improved among users of oral medications (p<0.001) (Figure 1a) . Among insulin users, glycemic control was unchanged (p=0.87) . Mexican American insulin users had a decrease in glycemic control (25.1% in 1988-94 to 9.9% in 2013-20, p=0.004) and had poorer glycemic control, overall, as compared to their non-Hispanic White or Black counterparts (Figure 1b-1d) .

Conclusions: Despite improvements in insulin formulations, insulin users have not seen improved glycemic control.


S.Venkatraman: None. E.Selvin: Other Relationship; Wolters Kluwer. M.Fang: n/a.

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