Racial/Ethnic Minority Groups Have Higher Risk of Diabetes at Lower BMIs

Compared to white Americans, racial/ethnic minority groups have a higher prevalence of diabetes and prediabetes at a lower body mass index (BMI), reports a study in Diabetes Care.

The study included approximately 4.9 million adults aged 20 years or older in 2012–2013. Data were drawn from a consortium of three US integrated healthcare systems (Kaiser Permanente, HealthPartners Minnesota, and Denver Health). Race/ethnicity was classified as white in 50% of individuals, Hispanic in 21.6%, Asian in 12.7%, black in 9.5%, Hawaiian/Pacific Islander in 1.4%, and American Indian/Alaska Native in 0.5%.

Cases of diabetes and prediabetes were ascertained by diagnosis, laboratory results, and use of antihyperglycemic medications. Racial/ethnic disparities in prevalence were assessed across BMI levels. The analysis included adjustment for socioeconomic and/or environmental disparities.

Standardized for age, estimated prevalence was 15.9% for diabetes and 33.4% for prediabetes. Prevalence of diabetes increased along with BMI in all racial/ethnic groups, although prediabetes prevalence did not. Diabetes prevalence was 27.7% in Hawaiians/Pacific Islanders, 22.2% in Hispanics, 21.4% in blacks, 19.6% in American Indians/Alaska Natives, and 19.3% in Asians, compared to 12.2% in whites. For prediabetes, prevalence was 37.1% in Asians, 36.7% in Hawaiian/Pacific Islanders, 35.3% in Hispanics, 32.0% in blacks, 31.1% in American Indians/Alaska Natives, and 31.0% in whites.

Compared to whites, all racial/ethnic minority groups had a higher diabetes prevalence at a given BMI, with the differences being most marked at lower BMI levels. In the normal weight range, 5% of whites had diabetes, compared to about 10% of Asians and American Indians/Alaska Natives and 13% to 14% of Hispanics, blacks, and Hawaiian/Pacific Islanders. On adjusted analysis, the association between BMI and diabetes was strongest in whites and lowest in blacks.

Obesity and race/ethnicity are major risk factors for diabetes, but racial/ethnic disparities in diabetes do not correspond to differences in obesity. This study in a very large insured population finds that Americans of racial/ethnic minority groups have a higher prevalence of diabetes and prediabetes at lower BMI levels.

The findings suggest that factors other than obesity contribute to the disproportionately high burden of diabetes/prediabetes in racial/ethnic minorities, who are at increased risk even at relatively low BMI levels. The findings “highlight the importance of tailored screening, prevention, and intervention strategies to mitigate the risk of diabetes and prediabetes,” the researchers write [Zhu Y, et al. Racial/ethnic disparities in the prevalence of diabetes and prediabetes by BMI: Patient Outcomes Research To Advance Learning (PORTAL) multisite cohort of adults in the U.S. Diabetes Care 2019; DOI: 10.2337/dc19-0532].

December 2019 (Vol. 11, Number 12)