Glycemic tests are an important tool in screening patients for diabetes and prediabetes but there is little literature describing changes in patterns of glycemic testing over time. Using claims data for Medicare Fee-for-Service (FFS) beneficiaries without diabetes, we examined trends and demographic variation in the use of glycemic screening tests. Beneficiaries with diabetes were identified by ICD diagnosis codes while tests were identified with HCPCS/CPT procedure codes.

The number of fully enrolled Medicare FFS beneficiaries without diagnosed diabetes ranged from 17.1 million in 2001 to 14.6 million in 2018. The total number of tests ranged from 2.7 million in 2001 to 4.8 million in 2018, and after 2009, the majority administered were HbA1c tests. The rate of glycemic testing was calculated as the percent of beneficiaries without diagnosed diabetes having at least one of any glycemic test per year. Testing rates were calculated by sex, age, race/ethnicity and state. The annual percentage of beneficiaries without diabetes who had any glycemic test increased from 10.6% in 2001 to 22.5% in 2018. Testing rate varied little across sex, age and race/ethnicity groups with 2 exceptions: beneficiaries age 85+ had a much lower testing rate (17.8% in 2018) than other age groups (23.6%); and beneficiaries of Asian or Pacific Islander descent had a much higher testing rate (31.7% in 2018) than other race/ethnicity groups (between 22.0–24.8%). However, testing rates did vary considerably among states: in 2018, ranging from a low of 11.1% in Wyoming to a high of 33.9% in Hawaii.

Glycemic testing for diabetes has increased steadily since 2010, largely due to increased use of HbA1c tests. However, fewer than 1 in 4 Medicare FFS beneficiaries were tested in 2018, suggesting that opportunities remain to improve screening and diagnosis of diabetes among older adults.


L.J.Andes: None. S.R.Benoit: None. D.B.Rolka: None. G.Imperatore: None. C.S.Holliday: None.

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