Molecular, Metabolomic and Nutritional Changes After Metabolic Surgery

Obesity is a major risk factor for Type 2 Diabetes (T2D) and cardiovascular diseases, such as hypertension and dyslipidemia. Recently, weight loss surgery (i.e., metabolic or bariatric surgery) has been shown to result in very good long-term glycemic control in patients with T2D and obesity. However, knowledge and data on molecular levels and metabolomics are still limited. This study will fill in these gaps and provide potential biomarkers for T2D. Lifestyle and dietary practices (LDP) influence the clinical outcome and metabolites in T2D. Although the roles of LDP is critical in ensuring optimal clinical outcomes, data is still limited especially on relating the LDP and metabolomics in T2D.

Study design

This is a prospective single centre study to explore molecular aspects and metabolomic changes among 102 obese individuals of different diabetes status, undergoing metabolic surgery, which is currently performed in Hospital Kuala Lumpur, Malaysia. Serial measurements of the selected markers will be made pre-operative (baseline), at 6 and 12 months follow up after surgery. Twenty (20) healthy individuals will be recruited as controls.

Study population

All subjects with obesity (Body Mass Index ≥ 30kg/m\^2 \[WHO classification\])) and diagnosed with pre-diabetes, T2D and non-diabetic (healthy) who are undergoing metabolic surgery at Hospital Kuala Lumpur will be recruited.

All patients referred by endocrinologists who are eligible and fulfill the inclusion and exclusion criteria for metabolic surgery will be included in the study until the sample size is achieved. Routinely, all patients will need to pay a visit to the clinic at 1, 2, 4 weeks after surgery, then 3, 6, 9, 12, 18, 24 months and after that, a life-long annual visit. Therefore, visit 6- and 12-month will be utilized for study follow-ups.

Metabolic surgery

The two most standard metabolic surgical procedures performed at Hospital Kuala Lumpur are laparoscopic sleeve gastrectomy and laparoscopic Roux en Y gastric bypass (RYGB). All the procedures are performed laparoscopically using 5-ports technique.

Eligibility Criteria:
Inclusion Criteria:

Patients' Inclusion Criteria

* BMI \> 30kg/m2
* Men and women
* Ages 18-65 years old
* Diabetes status (non diabetic, pre diabetes and diabetes)
* Patients who will undergo metabolic surgery

Healthy individuals' Inclusion Criteria

* BMI \< 30kg/m2,
* Men and women
* Ages 18-65 years old
* No diabetes
* No pre diabetes
* No other co-morbidities (high total cholesterol, high triglycerides, high blood pressure)

Exclusion Criteria:

Patients' Exclusion Criteria

* BMI \<30 kg/m2
* Use of medications that may affect body weight at screening or during a 3 month period prior
* Other medical conditions like Cushing's, acromegaly, Heart failure, Crohn's disease, etc
* Alcohol dependence

Healthy Individuals' Exclusion Criteria

* BMI \> 30 kg/m2 (obese)
* BMI \< 18.5 kg/m2 (underweight)
* Diabetes status (pre diabetes and diabetes)
* Use of medications that may affect body weight at screening or during a 3 month period prior
* Other co-morbidities (high total cholesterol, high triglycerides, high blood pressure, cancer)
* Other medical conditions like Cushing's, acromegaly, Heart failure, Crohn's disease, etc
* Alcohol dependence