Type 2 Diabetes (Sugar) Surgery: Who is it Suitable For?

Type 2 diabetes surgery, also known as metabolic surgery or bariatric surgery, is an effective treatment method that has become increasingly common in Turkey in recent years. So, who can benefit from this surgery, and how is patient selection conducted?

What is Type 2 diabetes surgery?

Metabolic surgery is a surgical method that regulates the body’s metabolism through changes made in the stomach and intestines, providing not only weight loss but also blood sugar control. Different techniques such as gastric bypass, sleeve gastrectomy, and mini gastric bypass can be applied. These surgeries help control type 2 diabetes by reducing insulin resistance and regulating metabolic hormones.

Who can have Type 2 diabetes surgery?

In Turkey, there are clear criteria determined by the Ministry of Health and SSI (Social Security Institution) for metabolic surgery:

Body Mass Index (BMI) Criteria: The lower BMI limit for metabolic surgery in Turkey is 30 kg/m². Surgery cannot be performed on patients with a BMI below 30. SSI coverage criteria are as follows:

• All patients with a BMI of 40 kg/m² and above are eligible for surgery.
• Patients with a BMI between 35-40 kg/m² who have obesity-related diseases such as type 2 diabetes, hypertension, and sleep apnea are suitable candidates.
• Patients with a BMI between 30-35 kg/m² who have uncontrolled type 2 diabetes can undergo surgery following a special evaluation.

Age Criterion: The accepted age range for surgery in Turkey is generally 18-65 years. A special evaluation is conducted for patients over 65, and general health status is critical. For adolescents under 18, the procedure can only be performed in very specific cases with pediatric endocrinology approval.

Diabetes Control Status: According to criteria set by the SSI, the patient must have received medical treatment for at least 6 months, and blood sugar must remain uncontrolled despite this treatment. An HbA1c value above 7%, failure to reach target values despite maximum-dose oral antidiabetic medication, or the requirement for insulin therapy are important indicators for surgery.

Duration of Diabetes: In practice in Turkey, it is expected that medical treatment has been attempted for at least 6-12 months after the diagnosis of diabetes. However, the success rate of surgery is higher in patients who have had diabetes for less than 10 years. In long-term diabetes, pancreatic functions may be more severely damaged.

What are the patient selection criteria?

A detailed pre-operative evaluation protocol is applied in hospitals in Turkey:

Multidisciplinary Team Evaluation: The patient must be evaluated by a general surgeon, endocrinologist, dietitian, psychiatrist or psychologist, and an anesthesiologist. This evaluation is mandatory for SSI approval.

Laboratory Tests: Comprehensive tests such as complete blood count, liver and kidney function tests, thyroid hormones, HbA1c, fasting blood sugar, insulin levels, and C-peptide levels are performed. The C-peptide test is especially important because it shows whether the patient is still producing their own insulin.

Imaging Procedures: Upper abdomen ultrasonography, and if necessary, upper gastrointestinal system endoscopy and chest X-rays are requested. If sleep apnea is suspected, polysomnography may be performed.

Psychological Evaluation: In the psychiatric evaluation mandatory for SSI approval in Turkey, it is investigated whether the patient has the mental capacity to adapt to lifestyle changes after surgery, as well as conditions like depression, anxiety disorders, or eating disorders.

Dietitian Follow-up: Dietitian follow-up for at least 6 months before surgery is mandatory. During this process, the patient receives nutritional education and prepares for the post-operative nutritional regimen.

Why is Type 1 diabetes not cured by surgery?

The natures of Type 1 and Type 2 diabetes are completely different, and this difference explains why metabolic surgery is only effective in Type 2:

Type 1 Diabetes is an Autoimmune Disease: In Type 1 diabetes, the body’s immune system completely destroys the insulin-producing beta cells in the pancreas. This process usually begins in childhood or young adulthood. Before surgery, the pancreas has already lost its ability to produce insulin.

Metabolic Surgery Cannot Restore Pancreatic Cells: No matter how successful the surgery is, it cannot recreate destroyed beta cells or stop the autoimmune process. Patients with Type 1 diabetes must take external insulin for life.

Basic Mechanism Difference: In Type 2 diabetes, the main problem is insulin resistance. The pancreas produces insulin, but the body’s cells do not respond adequately to this insulin. Metabolic surgery increases insulin sensitivity by providing weight loss and altering intestinal hormones. In Type 1, the issue is an insulin deficiency, not insulin resistance.

C-Peptide Level Difference: In patients with Type 1 diabetes, C-peptide levels are very low or undetectable, indicating the pancreas does not produce insulin. In Type 2, C-peptide is normal or high, indicating that surgery can be beneficial.

In Turkey, patients with Type 1 diabetes can only be evaluated for metabolic surgery due to obesity (not for the purpose of treating diabetes) if they meet the BMI criteria. However, even in this case, their diabetes will not improve; only weight control can be achieved.

Who is it not suitable for?

In Turkey, metabolic surgery is contraindicated or should not be performed in certain situations:

Patients with a BMI Below 30: According to Turkish regulations, surgery cannot legally be performed with a BMI below 30. No matter how severe the diabetes is, surgery is prohibited for patients below this limit.

Type 1 Diabetes Patients: For the reasons explained above, Type 1 diabetes patients do not benefit from this surgery in terms of diabetes control. It can only be considered if obesity is present and other criteria are met.

Uncontrolled Psychiatric Diseases: Uncontrolled psychiatric illnesses such as active psychosis, schizophrenia, severe depression, or bipolar disorder are absolute contraindications. These diseases must be treated first.

Alcohol and Substance Addiction: Patients with active alcohol or substance addiction cannot undergo surgery. They can be re-evaluated after overcoming the addiction and staying clean for at least 1 year.

Serious Heart and Lung Diseases: Conditions that greatly increase the risk of general anesthesia, such as severe heart failure, end-stage lung disease, or a recent heart attack, may prevent surgery. However, each patient is evaluated individually.

Advanced Liver Cirrhosis: The surgical risk is very high in patients with decompensated liver cirrhosis, and surgery is generally not performed.

Pregnancy: Metabolic surgery is strictly not performed on pregnant women. It is also recommended to avoid pregnancy for at least 12-18 months after surgery.

Cancer Treatment: Patients undergoing active cancer treatment or with a history of cancer within the last 5 years require special evaluation.

Patients Unable to Follow Post-Operative Care: Surgery is not suitable for patients who cannot attend regular hospital check-ups, take vitamin supplements, or follow nutritional recommendations.

Portal Hypertension and Esophageal Varices: These conditions associated with advanced liver disease pose significant surgical risks.