Individuals with anemias are often excluded from diabetes research when the population or outcome of interest is defined by HbA1c, as abnormal red blood cell turnover rates raise concern about the accuracy of measured HbA1c values. While racial/ethnic differences in the prevalence of certain anemias are well-known, the potential bias introduced by excluding individuals with anemias from research samples is less studied. We examined the prevalence of diagnosed anemias by race/ethnicity in a population of adults diagnosed with diabetes. Using data from a large healthcare system, we identified adults (≥21 years) diagnosed with type 2 diabetes from 2010-2016. We used ICD-9/codes to identify individuals diagnosed with anemia in the year prior to diabetes diagnosis and inherited hemoglobinopathies through follow-up. We used chi-square tests to compare the prevalence of these diagnoses by race/ethnicity. Among 78,2individuals, 5,434 (6.9%) had an anemia diagnosis in the 12 months prior to their diabetes diagnosis, with the most common being unspecified anemia (3.3%) and iron deficiency anemia (2.3%) . Black adults had the highest prevalence of any anemia (11% vs. Other race/ethnicity 8.8% vs. White 7% vs. Latino 6.1% vs. Asian 5.9%, p≤.0001) , unspecified anemia (5.4% vs. Other race/ethnicity 3.8% vs. White 3.5% vs. Latino 2.8% vs. Asian 2.4%, p≤.0001) , and iron deficiency anemia (3.6% vs. Other race/ethnicity 2.9% vs. White 2.2% vs. Latino 2.4% vs. Asian 1.9%, p≤.0001) . Black and Asian adults had the highest prevalence of inherited hemoglobinopathies (Asian 2.3% vs. Black 1.9% vs. Other race/ethnicity 1.3% vs. White 0.3% vs. Latino 0.3%, p≤.0001) .

In conclusion, among adults diagnosed with diabetes, Black adults had the highest prevalence of diagnosed anemias (>1 in Black adults had a diagnosis) . Excluding individuals from diabetes research based on diagnosis of anemia may disproportionately impact the relevance of the findings to Black adults.


C.Board: None. A.Gopalan: None. A.J.Karter: Research Support; Dexcom, Inc. R.W.Grant: None. O.Sofrygin: None.


National Institutes of Health (1R21DK130018-01)

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