Type 2 diabetes

What is type 2 diabetes?

Type 2 diabetes is a chronic metabolic disease characterized by a sustained elevation of blood glucose levels, known as hyperglycemia. This pathology results from a dual dysfunction within the body: insulin resistance at the level of peripheral cells and a progressive insufficiency in the secretion of insulin by the pancreas. Insulin plays an essential role in the regulation of blood sugar by facilitating the entry of glucose into cells to be used as a source of energy.

To illustrate this mechanism, imagine that insulin is a key that opens the doors of cells to allow glucose to enter. In type 2 diabetes, the lock (cell receptors) becomes less sensitive to the key (insulin), leading to an accumulation of sugar in the blood. This glycemic imbalance leads to a presence of excess glucose in the blood, which can cause serious damage in the long term.

What level of blood glucose is considered for the definition of diabetes?

The biological definition of diabetes is based on specific thresholds of fasting blood glucose. According to the recommendations of the Haute Autorité de Santé, a patient is considered diabetic if their fasting blood glucose is equal to or greater than 1.26 g/l (7 mmol/l) on two successive tests. A blood glucose measured at any time of the day equal to or greater than 2 g/l (11.1 mmol/l), associated with suggestive symptoms, also confirms the diagnosis of diabetes.

What screenings are available for diagnosing diabetes?

Screening for type 2 diabetes is primarily conducted through blood tests aimed at measuring the blood sugar levels. The fasting blood glucose test is the most commonly used: it involves measuring blood glucose after at least 8 hours of fasting.

The measurement of glycated hemoglobin (HbA1c) is also used to assess long-term glycemic control. An HbA1c level of 6.5% or higher is indicative of diabetes. Screening is particularly recommended for individuals with overweight, obesity, physical inactivity, an unbalanced diet, or family history of type 2 diabetes.

What causes type 2 diabetes?

Type 2 diabetes results from a complex interaction between genetic components and environmental factors. Among the main causes are:

1. Insulin resistance: the muscles, the liver, and the adipose tissue exhibit a decreased sensitivity to insulin, leading to an accumulation of sugar in the blood.
2. Decreased insulin secretion: over time, pancreatic beta cells become exhausted and no longer produce enough insulin to compensate for insulin resistance.
3. Genetic components: the presence of family history of type 2 diabetes increases the risk of developing the condition. Genetic variants may influence pancreatic function and insulin sensitivity.
4. Habits: an unbalanced diet, high in fast sugars and saturated fats, combined with physical activity that is insufficient, promotes overweight and obesity.
5. Gut flora: recent studies suggest that the gut flora plays a role in the development of type 2 diabetes. An alteration in the composition of the intestinal microbiota could influence the mechanisms of inflammation and insulin resistance.
6. Others: smoking, chronic stress, certain endocrine disorders, and the use of certain antidiabetic medications can also contribute to the development of diabetes.

Medical research continuously explores the underlying mechanisms to better understand the development of diabetes. Understanding these causes is essential to implement appropriate preventive measures and reduce the risk of developing this condition.

What are the symptoms and signs of diabetes?

Type 2 diabetes is often asymptomatic at the beginning, which complicates its early detection. However, certain clinical signs may appear:

• Polyuria: Frequent need to urinate, especially at night.
• Polydipsia: Increased thirst and increased fluid intake.
• Persistent fatigue or exhaustion.
• Blurred vision: Visual difficulties due to prolonged hyperglycemia.
• Slow healing: Delayed healing of wounds and infections.
• Unexplained weight loss: Despite a normal or increased appetite.
• Recurrent infections: Especially skin or urinary infections.
• Tingling or numbness: A sensation of decreased sensitivity in the extremities, resulting from nerve damage.

If you experience one or more of these symptoms, it is crucial to consult a healthcare professional for screening. An early diagnosis allows for effective management and helps prevent serious complications associated with diabetes.

How is type 2 diabetes diagnosed?

The detection of type 2 diabetes involves several key steps:

1. Medical history: Your doctor gathers information about your symptoms, personal and family history, as well as your habits.
2. Biological tests:
   • Fasting blood glucose: Measurement of the blood sugar level after fasting for at least 8 hours. A value equal to or greater than 1.26 g/l in two successive measurements indicates diabetes.
   • Glycated hemoglobin (HbA1c): Indicator of glycemic control over the past two to three months. A value greater than or equal to 6.5% suggests diabetes.
3. Additional tests: Depending on the results, your doctor may order further tests to screen for potential complications.

What treatments are available?

Changes in habits

Type 2 diabetes is strongly influenced by diet and lifestyle habits, so certain modifications daily can help to better manage the diabetes:

• Balanced diet: adopting a diet rich in fiber, fruits, and vegetables while limiting fast sugars and saturated fats helps control blood glucose levels and promotes weight loss.
• Regular physical activity : engaging in at least 30 minutes of moderate exercise per day enhances insulin sensitivity, aids in weight loss, and lowers the risk of cardiovascular disease.
• Weight loss: in overweight or obese patients, a weight reduction of 5 to 10% can significantly improve glycemic control.

Oral antidiabetic drugs

When lifestyle and dietary modifications are insufficient, antidiabetic medications are prescribed. The main classes include:

• Metformin: reduces hepatic glucose production and enhances insulin sensitivity.
• Sulfonylureas and glinides: stimulate insulin secretion.
• DPP-4 inhibitors and GLP-1 agonists: enhance incretin hormones, promoting insulin secretion in response to meals.
• SGLT2 inhibitors: increase the excretion of glucose through the kidneys.

The choice of treatment is individualized based on the patient’s characteristics, efficacy, side effects, and associated comorbidities.

Insulin therapy

If oral antidiabetic medications and lifestyle modifications are no longer sufficient to control blood glucose levels, insulin therapy may become necessary. When the pancreas is unable to produce adequate insulin, the administration of exogenous insulin aids in regulating blood sugar levels. Patients receive insulin injections to compensate for the deficiency, which is crucial to prevent complications associated with chronic hyperglycemia.

Therapeutic education

Therapeutic education is a fundamental component in the management of type 2 diabetes. It aims to:

• Inform the patient about their condition and treatments.
• Developing self-management skills, including blood glucose monitoring.
• Prevent complications by adopting health-promoting behaviors.
• Promote treatment adherence and improve quality of life.

Educational programs are often offered by specialized centers, hospitals, or patient associations. They help patients understand the mechanisms and encourage them to adopt a healthy lifestyle.

Is insulin treatment necessary for type 2 diabetes?

In type 2 diabetes, the use of insulin therapy is not routine. However, it may become necessary in certain situations:

• Failure of oral antidiabetic treatments: When medications can no longer maintain adequate blood glucose levels.
• Very high blood glucose levels at diagnosis: Requiring prompt intervention to prevent complications.
• Pregnancy: Some patients require insulin therapy to regulate blood glucose levels and prevent fetal risks.
• Acute or chronic complications: Affecting renal or hepatic function, thereby limiting the use of certain medications.

As the condition progresses, the pancreas may become exhausted, necessitating the use of insulin. This is administered via subcutaneous injections, following a dosage schedule tailored to each patient. Medical monitoring is essential to adjust doses and prevent episodes of hypoglycemia.

What are the potential complications and consequences?

Cardiovascular diseases

Elevated blood sugar levels promote atherosclerosis, increasing the risk of cardiovascular diseases such as:

• Myocardial infarction: obstruction of the coronary arteries supplying the heart.
• Strokes: disruption of blood flow in the brain.

Peripheral Artery Disease (PAD)

Peripheral artery disease (PAD) is a condition affecting the arteries of the legs, causing:

• Pain during walking, referred to as intermittent claudication.
• Ulcers and delayed healing.
• Increased risk of amputation in cases of severe ischemia.

Diabetic retinopathy

Retinopathy is a condition affecting the blood vessels of the retina, which can lead to:

• Decreased vision.
• Blindness in the absence of appropriate treatment.

Regular ophthalmological examinations are essential for preventing this condition.

Diabetic nephropathy

Nephropathy affects the kidneys, leading to:

• Chronic kidney failure.
• Need for dialysis or kidney transplantation at an advanced stage.

Diabetic neuropathy

Neuropathy results from damage to peripheral nerves, causing:

• Pain, tingling, numbness, primarily in the feet and hands.
• Perte de sensation, augmentant le risque de blessures et d’infections.
• Digestive disorders or cardiac issues in cases of autonomic nervous system involvement.

What is the difference between type 1 and type 2 diabetes?

Although type 1 and type 2 diabetes share the common feature of impaired blood glucose regulation, they differ in their mechanisms and management:

• Type 1 diabetes:
  • Autoimmune pathology where the immune system destroys the insulin-producing pancreatic beta cells.
  • Generally occurs in children and young adults.
  • Requires insulin therapy from the time of diagnosis.
  • Sudden onset with pronounced symptoms.
• Type 2 diabetes:
  • Results from insulin resistance associated with a progressive decline in insulin secretion.
  • Often occurs after the age of 40, but the average age tends to decrease due to lifestyle changes.
  • Initial treatment based on lifestyle modifications and oral antidiabetic medications.
  • Slow progression and often asymptomatic in the early stages.

How can prevention influence the risk of type 2 diabetes?

Prevention is essential in mitigating the risk of developing type 2 diabetes. Evidence suggests that embracing healthy lifestyle practices can delay or avert the onset of the disease:

• Maintaining a healthy weight: In overweight or obese patients, weight loss improves insulin sensitivity.
• Balanced diet: Focus on foods rich in fiber, fruits, vegetables, whole grains, and limit saturated fats and added sugars.
• Regular physical activity: At least 150 minutes of moderate exercise per week improves blood glucose regulation and cardiovascular health.
• Stress reduction: Chronic stress can affect blood glucose levels, so it is important to manage stress through relaxation techniques or meditation.
• Smoking cessation.
• Lifestyle modifications to reduce risks.

According to the WHO, these preventive measures can have a significant impact on the prevalence of the disease. Prevention is particularly important for individuals with a family history of type 2 diabetes or risk factors.

Why is early diagnosis of type 2 diabetes crucial?

An early diagnosis of type 2 diabetes is crucial for several reasons:

• Prevention of complications: Early treatment initiation can slow disease progression and reduce the risk of serious complications.
• Lifestyle adaptation: Behavioral changes are more effective when implemented at the onset of the disease.
• Improvement of quality of life: Optimal glycemic control reduces symptoms and enhances overall well-being.
• Therapeutic education: Early patient information allows for better management and autonomy.
• Reduction in healthcare costs: Preventing and reducing hospitalizations and long-term expensive treatments.

It is therefore recommended for at-risk individuals to undergo regular screenings to detect type 2 diabetes as early as possible.