Homocysteine After Laparoscopic Roux-enY Gastric Bypass

Study Overview
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Brief Summary
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Changes in homocysteine values after bariatric surgery remain controversially discussed. This is the first comprehensive summary to depict timeline changes in homocysteine levels following laparoscopic roux-en-Y gastric bypass.

Detailed Description
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Homocysteine is an independent risk factor for cardiovascular disease. Changes in homocysteine levels following bariatric surgery remain controversially discussed. 708 consecutive patients underwent laparoscopic roux-en-Y gastric bypass over a 6 year period. Throughout their routine follow-up, demographic data as well as homocysteine, folate and vitamin B12 were retrospectively collected at the timepoints: preoperatively, at 3, 6, 9, 12, 18, 24, 36, 48, 60, 72, 84, and 96 months postoperatively. In order to reveal clinical relevance of the results, patients were sent a special questionnaire accompanied by an informed consent form for participation and asked for cardiovascular disease events (myocardial infarction, stroke, deep venous thrombosis) or any other hospital stay after the surgery and cross checked with two region wide databases which account for approx. 80% of all hospital contacts in the region. Additionally, the database was networked with the statewide death registry in order to reveal deceased subjects and data about their demise through the beforementioned databases was collected.

Official Title
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Homocysteine After Laparoscopic Roux-enY Gastric Bypass: a Comprehensive Evalutation in 708 Patients

Conditions
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Obesity, Morbid, Homocystine; Metabolic Disorder, Bariatric Surgery Candidate, Folate Deficiency, Vitamin B 12 Deficiency

Intervention / Treatment
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* Procedure: laparoscopic long limb roux-en-Y gastric bypass


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: BMI > 40kg/m2 or BMI > 35 kg/m2 including relevant comorbidities Age between 18 to 75 years suitable for operation, consent no contraindications for the operation Exclusion Criteria: BMI < 35 kg/m2 age below 18 or above 75 years not able to consent to the operation severe medical conditions not applicable for general anaesthesia non compliance

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| RYGB Patients<br>Laparoscopic long limb roux-en-Y gastric bypass group. All consecutive patients eligible for bariatric surgery. | Procedure: laparoscopic long limb roux-en-Y gastric bypass<br>* standard laparoscopic roux-en-Y gastric bypass (biliopancreatic limb 40 to 60 cm, alimentary limb 150 cm)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Homocysteine in µmol/l assessed by CMIA technique. | Measured by Chemiluminescent microparticle immunoassay (CMIA) technique in µmol/l. Change of homocysteine over the timeframe at the timepoints: preoperatively, 3, 6, 9, 12, 18, 24, 36, 48, 60, 72, and 96 months postoperatively. | timepoints: preoperatively, 3, 6, 9, 12, 18, 24, 36, 48, 60, 72, and 96 months postoperatively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Weight in kg measured by a standard scale. | Change of weight in kg over the timeframe at the timepoints: preoperatively, 3, 6, 9, 12, 18, 24, 36, 48, 60, 72, and 96 months postoperatively. | timepoints: preoperatively, 3, 6, 9, 12, 18, 24, 36, 48, 60, 72, and 96 months postoperatively | 
| Folate in nmol/l assessed by ELCIA method. | ELCIA: electrochemiluminescent immunoassay Change of folate in nmol/l over the timeframe at the timepoints preoperatively, 3, 6, 9, 12, 18, 24, 36, 48, 60, 72, and 96 months postoperatively. | timepoints: preoperatively, 3, 6, 9, 12, 18, 24, 36, 48, 60, 72, and 96 months postoperatively | 
| Vitamin B12 in pmol/l assessed by CMIA technique. | Change of vitamin B12 in pmol/l over the timeframe at the timepoints preoperatively, 3, 6, 9, 12, 18, 24, 36, 48, 60, 72, and 96 months postoperatively. | timepoints: preoperatively, 3, 6, 9, 12, 18, 24, 36, 48, 60, 72, and 96 months postoperatively | 
| Number of cardiovascular events assessed by a questionnaire and cross checking with 2 state wide databases. | Assessed conditions: events of myocardial infarction, stroke, deep vein thrombosis and peripheral artery disease which were not preexistent. | Through study attendance the specific date of the incident was assessed and assigned to the timepoints: preoperatively, 3, 6, 9, 12, 18, 24, 36, 48, 60, 72, and 96 months postoperatively | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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bariatric surgery, gastric bypass, homocysteine, folate, vitamin b12