By Israel Hodish, M.D., Ph.D., co-founder and clinical research lead
Type 2 diabetes affects about 10% of the general population in the United States. Yet, it occurs in nearly 15% of the Native-American population, nearly 12% of the non-Hispanic black population, and nearly 13% of the Hispanic population, according to the American Diabetes Association. Why does type 2 diabetes impact some ethnicities and races more than others?
Diabetes has three major risk factors: age, weight, and genetic predisposition. Genetic predisposition means that there are either specific genes that make a person more prone to develop diabetes, or there are genes that are more likely to be expressed.
Genetic predisposition has two main aspects. First, individuals who have one parent with diabetes are three times more likely to have diabetes, and individuals who have both parents with diabetes are five times more likely than those with no family history.
The second aspect related to genetic predisposition is racial or ethnic background. Individuals who are of African American, Native American, Native Hawaiian, Japanese or Hispanic descent have higher chances to have diabetes than whites. People in these groups are at an increased risk whether they have normal weight or are overweight.
But the disparity does not end there.
In the United States, people of Native American, Alaska Native, African American or Hispanic descent are at higher risk than whites to develop severe diabetes complications and are about twice as likely to die from diabetes. Unfortunately, this means that for a variety of reasons, it is harder for people in these demographic groups to manage their disease.
Likely one of the major reasons for the disparity is different rates of disease progression. Type 2 diabetes is a condition of progressive insulin deficiency. Over time individuals secrete less and less insulin. As a result, different medications are used in different stages. After about a decade with diabetes, most patients tend to need insulin therapy. They just stop secreting sufficient insulin for non-insulin medications to work. However, individuals of certain races or ethnicities progress much faster to become insulin deficient.
So, what is the connection between early insulin deficiency and developing complications? Once a person becomes overtly insulin deficient, they require insulin therapy to manage their type 2 diabetes. Most patients who use insulin therapy face major difficulties in bringing their diabetes under control. Insulin requirements are highly dynamic, and thus insulin doses need to be adjusted very frequently to achieve and maintain therapy goals in a safe way. In fact, insulin therapy is likely the most dynamic therapy in medicine.
Yet, due to limited availability, physicians can usually adjust patients’ insulin doses only a few times per year, which is not nearly enough. Since it is hard to keep one’s diabetes in good control once insulin therapy is needed, individuals who progress to insulin deficiency earlier are more likely to have a longer period of poor diabetes control.
With this much added risk, what should an individual do when they are diagnosed with type 2 diabetes? My recommendation is the same no matter one’s race, ethnicity or medications. The key to avoiding disease complications is to keep glucose levels, or hemoglobin A1c, optimal and stable at any stage of the disease. Since most patients will require insulin therapy at some point, frequent insulin therapy dose optimizations is critical.