A peer-reviewed study, published in The Lancet Medical Journal suggests there are five types of diabetes. Could diabetes be more complex than we once thought? Could diabetes be segmented into five separate diseases?

What is diabetes?

Diabetes is an incurable disease which prohibits the body’s ability to produce and respond to insulin.  Currently, diabetes is classified into two main forms, type 1 and type 2.

Type 1 diabetes is an autoimmune disease which manifests in childhood.  In type 1 diabetes, the body’s white blood cells attack the insulin-producing cells in the pancreas.  As a result, individuals with Type 1 diabetes rely on the injection of insulin for the remainder of their lives.

Type 1 diabetes affects 10 percent of individuals with diabetes.  96 percent of children diagnosed with diabetes have type 1.  Type 1 diabetes in children is commonly diagnosed between the ages of 10 and 14.  The prevalence of type 1 diabetes in children and young people (under the age of 19) is 1 in every 430-530 and the incidence of type 1 in children under 14 years of age is 24.5/100,000 (Diabetes UK, 2014).

Type 2 diabetes is the result of insulin resistance, meaning that the pancreas does not produce enough insulin or the body’s cells do not respond to the insulin produced.  As type 2 diabetes is a mixed condition, with varying degrees of severity, there are a few methods to manage the disease, including dietary control, medication and insulin injections.

Type 2 diabetes is the most common form of diabetes, affecting 90 percent of individuals with diabetes, and has now become a global burden.  The global prevalence of diabetes has almost doubled from 4.7 percent in 1980 to 8.5 percent in 2014, with a total of 422 million adults living with diabetes in 2014.  It is expected to rise to 592 million by 2035.  In 2012, diabetes accounted for 1.5 million deaths globally with hypertension causing a further 2.2 million deaths.  43 percent of these deaths occurred before 70 years of age.  Previously type 2 diabetes was commonly seen in young adults but is now commonly seen in children as well.  In 2017, 14% more children and teenagers in the UK were treated for diabetes compared to the year before (World Health Organization, 2016).

In both forms of diabetes, hyperglycemia can occur which can lead to number of associated complications including renal disease, cardiovascular disease, nerve damage and retinopathy.

The novel subgroups of adult-onset diabetes and their association with outcomes: a data-driven cluster analysis of six variables – peer-review study

This new research studied 13,270 individuals from different demographic cohorts with newly diagnosed diabetes, taking into consideration body weight, blood sugar control and the presence of antibodies, in Sweden and Finland.

This peer-reviewed study identified 5 disease clusters of diabetes, which have significantly different patient characteristics and risk of diabetic complications.  The researchers also noted that the genetic associations in the clusters differed from those seen in traditional type 2 diabetes.

Cluster One – Severe autoimmune diabetes (SAID)

SAID is similar to type 1 diabetes.  SAID manifests in childhood, in patients with a low BMI, have poor blood sugar and metabolic control due to insulin deficiency and GADA.  6% of individuals studied in the ANDIS study were identified with having SAID.

Cluster Two – Severe insulin-deficient diabetes (SIDD)

SIDD is similar to SAID, however, GADA is negative.  This means that the characteristics of SIDD are the same as SAID, young, of a healthy weight and struggled to make insulin, however, SIDD is not the result of an autoimmune disorder as no autoantibodies are present.  Patients have a higher risk of diabetic retinopathy.  18% of subjects in the ANDIS study were identified with having SIDD.

Cluster Three – Severe insulin-resistant diabetes (SIRD)

SIRD is similar to that of type 2 diabetes and is characterised by insulin-resistance and a high BMI.  Patients with SIRD are the most insulin resistant and have a significantly higher risk of kidney disease, and microalbuminuria, and non-alcoholic fatty liver disease.  15% of subjects in the ANDIS study were identified as having SIRD.

Cluster Four – Mild obesity-related diabetes (MOD)

MOD is a mild form of diabetes which generally affects a younger age group. This is not characterised by insulin resistance but by obesity as their metabolic rates are close to normal.  22% of subjects in the ANDIS study were identified as having MOD.

Cluster Five – Mild age-related diabetes (MARD)

MARD is the most common form of diabetes manifesting later in life compared to the previous four clusters.  Patients with MARD have mild problems with glucose regulation, similar to MOD.  39% of subjects in the ANDIS study were identified with having MARD.

This new sub-classification of diabetes could potentially enable doctors to effectively diagnose diabetes earlier, through the characterisation of each cluster, including: BMI measurements, age, presence of autoantibodies, measuring HbA1c levels, ketoacidosis, and measuring fasting blood glucose levels.  This will enable a reduction in the incidence of diabetes complications and the early identification of associated complications, and so patient care can be tailored, thus improving healthcare (NHS, 2018) (The Week, 2018) (Ahlqvist, et al., 2018) (Collier, 2018) (Gallagher, 2018).

The Randox diabetes reagents cover the full spectrum of laboratory testing requirements from risk assessment, using our Adiponectin assay, to disease diagnosis and monitoring, using our HbA1c, glucose and fructosamine assays, to the monitoring of associated complications, using our albumin, beta-2 microglobulin, creatinine, cystatin c, d-3-hydroxybutyrate, microalbumin and NEFA assays.

Whilst this study is valuable, alone it is not sufficient for changes in the diabetes treatment guidelines to be implemented, as the study only represents a small proportion of those with diabetes.  For this study to lead the way, the clusters and associated complications will need to be verified in ethnicities and geographical locations to determine whether this new sub-stratification is scientifically relevant.

References

Ahlqvist, E. et al., 2018. Novel subgroups of adult-onset diabetes and their association with outcomes: a data-driven cluster analysis of six variables. [Online]
Available at: http://www.thelancet.com/journals/landia/article/PIIS2213-8587(18)30051-2/fulltext?elsca1=tlpr
[Accessed 16 April 2018].

Collier, J., 2018. Diabetes: Study proposes five types, not two. [Online]
Available at: https://www.medicalnewstoday.com/articles/321097.php
[Accessed 16 April 2018].

Diabetes UK, 2014. Diabetes: Facts and Stats. [Online]
Available at: https://www.diabetes.org.uk/resources-s3/2017-11/diabetes-key-stats-guidelines-april2014.pdf
[Accessed 16 April 2018].

Gallagher, J., 2018. Diabetes is actually five seperate diseases, research suggests. [Online]
Available at: http://www.bbc.co.uk/news/health-43246261
[Accessed 16 April 2018].

NHS, 2018. Are there actually 5 types of diabetes?. [Online]
Available at: https://www.nhs.uk/news/diabetes/are-there-actually-5-types-diabetes/
[Accessed 16 April 2018].

The Week, 2018. What are the five types of diabetes?. [Online]
Available at: http://www.theweek.co.uk/health/92048/what-are-the-five-types-of-diabetes
[Accessed 16 April 2018].

World Health Organization, 2016. Global Report on Diabetes, Geneva: World Health Organization.