There are concerns that doctors could misdiagnose diabetes in India due to higher rates of type 2 diabetes in younger and slimmer people. A new study has shown that an existing genetic test could accurately diagnose diabetes in people of Indian heritage.
Although people often use the word diabetes to describe one condition, there are actually two different types of diabetes.
Type 1 diabetes is an autoimmune disease that causes damage to the beta cells in the pancreas that produce insulin. A lack of insulin is the primary characteristic of type 1 diabetes.
Treatment involves regular injections with insulin.
Type 2 diabetes is the more common form of diabetes. It is not an autoimmune condition and typically involves resistance to rather than a lack of insulin.
Treatments include medications to increase insulin sensitivity and lifestyle changes, such as following a healthful diet.
Previously, experts have associated the two forms with different age groups:
- Type 1 diabetes tends to occur in younger people.
- Type 2 is more likely to occur in people over 45 years of age who have a high body mass index (BMI).
However, this view is shifting due to rising rates of childhood obesity and recent findings that type 1 diabetes can occur later in life.
This has led to concerns regarding misdiagnosis, particularly in Indian populations, where there is a higher prevalence of type 2 diabetes in younger and slimmer people.
Furthermore, scientists have carried out most research on type 1 diabetes in European populations, which means existing diagnostic tools may not apply.
Misdiagnosis in diabetes is a growing concern. One recent study of 583 participants from the population-based Exeter Diabetes Alliance for Research in England (DARE) in the United Kingdom found that almost 40% of adults with type 1 diabetes did not receive a correct initial diagnosis and received treatment for type 2 diabetes.
Diagnosing diabetes accurately is vital because administering the wrong treatment could have severe consequences, such as diabetic ketoacidosis.
“Diagnosing the right diabetes type is an increasingly difficult challenge for clinicians, as we now know that type 1 diabetes can occur at any age. This task is even harder in India, as more cases of type 2 diabetes occur in people with low BMI,” explains Dr. Richard Oram of the Institute of Biomedical and Clinical Science at the University of Exeter Medical School in the U.K.
A collaborative study between researchers in Hyderabad in India and the University of Exeter has looked at the effectiveness of current genetic risk scores for diagnosing type 1 diabetes in Indian populations.
The authors published the study in Scientific Reports.
The researchers assessed whether the genetic risk score can effectively discriminate between type 1 and type 2 diabetes in people from Pune in the west of India, who were of Indo-European ancestry.
They analyzed 262 people with confirmed type 1 diabetes, 345 people with type 2 diabetes, and a control group of 324 people who did not have diabetes. They then compared the outcomes with those of European people from the Wellcome Trust Case Control Consortium study.
The researchers found that the current genetic risk score is effective at diagnosing diabetes in Indian populations, even though the original data were from European people.
However, the team also identified new genetic differences between European and Indian populations, making the test more accurate for Indian people.
They found nine new genetic variants (single-nucleotide polymorphisms, or SNPs) that correlate with type 1 diabetes in both groups that doctors could use to predict the onset of the disease in Indian people.
“It’s interesting to note that different SNPs are more abundant among Indian and European patients. This opens up the possibility that environmental factors might be interacting with these SNPs to cause the disease,” explains Dr.G. R Chandak, the scientist leading the study at the CSIR-Centre for Cellular and Molecular Biology in Hyderabad, India.
The results are good news for doctors using this score to diagnose people in India.
“We look forward to using this test in diabetic patients from different parts of India, where the physical characteristics of diabetic patients differ from the standard description.”
– Dr. Chittaranjan Yajnik, KEM Hospital & Research Centre in Pune, India
However, India is a vast country with a lot of genetic diversity, so researchers must also validate this test in other ethnic groups.
Over time, the team hopes to develop a genetic test for type 1 diabetes specific to people with Indian ancestry.
A combined approach, including both genetic risk scores and clinical features, such as auto-antibodies indicative of type 1 diabetes), will be the most effective way to diagnose the disease.