Diabetes is defined by too high a level of glucose (sugar) in the blood. Blood sugar levels are normally controlled by insulin, a hormone secreted by the pancreas. In healthy individuals, insulin promotes the absorption of sugar by cells so that it can be used later as a source of energy.

Key figures

INSERM study in 2019

3.5M

of French people affected
in 2019

451M

cases worldwide
in 2017

693M

of estimated cases
in 2045

5M

deaths attributed to type 2 diabetes
in 2017

850M$

in public health expenditure in relation to type 2
in 2017

77ans

Mean age of peak incidence

Symptoms / Severity

Diabetes develops silently over many years and remains asymptomatic for a long time. For these reasons, the diagnosis of diabetes is most often made during a blood test for another pathology.

The symptoms that may appear (apart from the symptoms specific to the complications of diabetes) are not very specific:

  • Feeling of hunger and thirst
  • Tired
  • Frequent need to urinate
  • Dry skin
  • Itching
  • Blurred vision

Causes / Risk factors

There are two types of diabetes whose causes and management are different:

  • Type 1 diabetes occurs in young subjects, often during childhood, and is due to an autoimmune destruction of the pancreatic islets which no longer secrete insulin.
  • Type 2 diabetes (90% of diabetes cases) occurs later, in adulthood, in relation to insulin resistance (hepatic, muscle and fat cells are less sensitive to the action of insulin; the result is increase in blood glucose levels and insulin secretion by the pancreas – hyper insulinemia, up to the exhaustion of pancreatic cells).

The main risk factors for type 2 diabetes are linked to lifestyle – too fatty and too sweet food, physical inactivity, obesity. Other factors that can intervene are certain medications (eg neuroleptics) or the unbalanced intestinal flora (microbiota).

Evolution / Consequences

The chronic complications of diabetes generally occur in the long term after 10 to 15 years of evolution and are essentially linked to multi-organ atherosclerosis:

  • CVA : cerebral vascular accident
  • Myocardial infarction : each year there are 1000 deaths among 10,000 diabetics hospitalized for a myocardial infarction
  • Lower limb amputations – arteriopathy : each year 9,000 diabetics are amputated
  • Dialysis – nephropathy : every year 3,000 diabetics are on dialysis or undergo a kidney transplant

Other diabetes-related complications are:

  • ocular – diabetic retinopathy
  • peripheral nerves – neuropathy
  • hepatic – diabetes is an independent risk factor for the accumulation of fat in the liver (“fatty liver disease” or NAFLD) and for liver cancer. Learn more.

How is it treated?

Lifestyle measures play a major role in the management of diabetes and aim to:

  • A balanced diet
  • an increase in physical activity
  • weight loss

The main drugs used are:

  • metformin, sulfonylureas to stimulate insulin secretion,
  • DDP4 inhibitors that block the degradation of GLP1
  • SGTL2, or iSGTL2 which inhibit glucose reabsorption in the kidney

Glucagon-like peptide-1 (GLP1) receptor agonists are now widely used and act by several mechanisms. They slow down gastric emptying, limit appetite and stimulate insulin secretion, but only in the event of a rise in blood sugar (thus avoiding the risk of hypoglycaemia).

Is there research on this pathology?

Research on the molecular bases of diabetes up to the improvement of the management of diabetic patients is very old and still extremely active. It has enabled considerable progress in the understanding and management of this condition, so that today diabetes is more of a condition than a disease.

ICAN's response

At the IHU, research on diabetes goes from the most fundamental aspects to helping patients on a daily basis. Thus, the teams are interested in the links between diabetes and other metabolic diseases such as non-alcoholic fatty liver disease (NAFLD) with original research avenues: role of lipids in cell membranes (sphingolipids) or certain liver cells in particular involved in inflammation.

They are also studying the relationship between the aging of adipose tissue and insulin resistance, a true pre-diabetic state.

The impact on insulin resistance of bariatric surgery, which aims to reduce fat mass, is also actively studied.

A new line of research to which the IHU is contributing has just opened up, it concerns the impact of diabetes on heart disease, in particular heart failure, and aims in particular to understand the beneficial effects on the heart of new antidiabetic drugs.

One of the feared complications of diabetes is the diabetic foot which can lead to amputation; the teams have implemented innovative treatment for this disease and, in collaboration with engineering students on campus, have developed a connected insole to prevent it.