Ethnicity Can Affect Risk for Diabetes Complications 

A diabetes patient’s risk for chronic kidney disease or cardiovascular disease can be impacted by various factors, including their ethnicity. 

A new approach is needed to identify the risk of diabetes complications due to the heterogeneity and progression of diabetes. A few recent studies have shown diabetes can be categorized into smaller groups, thus improving treatment and preventing complications for patients by quickly identifying patients in the subgroups at risk. In prior studies, diabetes subgroups were formed among European, Japanese, and Asian-Indian participants based on phenotype characteristics. The studies had demonstrated that the risk of complication differed among the subgroups. However, it is unclear whether the data can be applied to the U.S. minority population.  

This analysis aims to classify diabetes into subgroups and to explore the connection between diabetes complications and ethnic background. Mediators of Atherosclerosis in South Asians Living in America (MASALA) and the Multi-Ethnic Study of Atherosclerosis (MESA) were two cohort studies utilized in this analysis. A total of 906 south Asian participants aged 40 to 84 years old with no cardiovascular disease history were included in the MASALA study. 6814 participants from white, Black, Hispanic, and Chinese American ethnicities aged 45 to 85 years without clinical cardiovascular disease were included in the MESA analysis. 

K- means clustering model was utilized in this analysis to classify subgroups for this study by using body mass index, HbA1c, age during diabetes onset, and homeostatic model assessment for beta-cell function and insulin resistance; participants taking insulin medication was not used in the K- means clustering model. Silhouette index was calculated to determine the uniformity of the subgroups. For this analysis, the silhouette index was 0.21. Cardiovascular risk factors, chronic kidney disease, and coronary artery calcium were assessed in this study. 

A total of 1293 participants with diabetes were included in both studies. 46% of participants were female. There were 17% south Asian participants, 16% non-Hispanic white participants, 10% Chinese participants, 30% African American participants, and 25% Hispanic participants. The researchers identified five subgroups in this analysis, including diabetes diagnosis at an older or younger age, the use of insulin, obesity, and hyperglycemia.  43% of participants were aged over 30 at diabetes onset, 26% had higher HbA1c levels, 20% had higher BMI levels, and  9% took insulin medications. Diabetes diagnosed at a younger age had the least number of participants, with 1%. 

In the older age diabetes onset subgroup, there were 17% south Asian participants, 38% white participants, 24% Chinese participants, 44% African American participants, and 34% Hispanic participants. In the younger age diabetes onset subgroup, there were 2% south Asian participants, 3% white participants, 0% Chinese participants, 2% African American participants, and 2% Hispanic participants. In the higher HbA1c levels subgroup, there were 25% south Asian participants, 8% white participants, 8% Chinese participants, 32% African American participants, and 31% Hispanic participants. There were 21% south Asian participants in the higher BMI subgroup, 23% white participants, 4% Chinese participants, 31% African American participants, and 26% Hispanic participants. For the participants who used insulin, 13% South Asians, 14% non-Hispanic whites, 2% Chinese participants, 38% African American participants, and 29% Hispanic participants.  

The hyperglycemia subgroup had the highest adjusted 10- year ASCVD score with 23.5, and the younger diabetes onset subgroup had the lowest score of 15.4. 34% of participants had a coronary artery calcium score greater than 100, and 60% had a score greater than 0. Being diagnosed at a younger age had a higher predictive overall coronary artery calcium score, >0 with 71.7% and >100 with 47.7%. Participants using insulin medication had a higher predicted probability for prevalent CKD with 18.8%. 

The highest risk ASCVD subgroup for all minority groups except south Asians was diabetes diagnosis at an older age. Among south Asian participants, higher HbA1c levels were the highest subgroup. 

The study demonstrated a difference in the risk of chronic kidney disease and cardiovascular disease risk factors amongst the subgroups. Also, the study noted that there was also a difference of minority groups found between the subgroups. Because the risk of complications was different among subgroups, the physician can personalize treatment and prevent diabetes complications by identifying patients from subgroups.  

Practice Pearls: 

• Diabetes onset at an older or younger age, the use of insulin, higher BMI, and higher HbA1c were the five subgroups identified in this study. 
• Diabetes diagnosed at an older age was the highest ASCVD risk subgroup among White, Chinese, Hispanic, and African American participants, while hyperglycemia was the highest subgroup among south Asians.  
• This study suggests that categorizing diabetes into subgroups may help physicians provide the best treatment and preventive approaches by correlating the risk of diabetes complications with the subgroups. 

Monostra, Michael. “Diabetes Complications Differ According to Ethnicity, Disease-Related Subgroups.” Healio, Jan 27, 2021. 

Bancks, Michael P et al. “Association of Diabetes Subgroups With Race/Ethnicity, Risk Factor Burden and Complications: The MASALA and MESA studies.” The Journal of clinical endocrinology and metabolism, dgaa962. 27 Jan. 2021, doi:10.1210/clinem/dgaa962 

Alexis Dunn, PharmD. Candidate, Florida Agricultural & Mechanical University, College of Pharmacy and Pharmaceutical Sciences 

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