CHANGES IN SERUM HOMOCYSTEINE LEVELS AFTER ROUX-EN-Y GASTRIC BYPASS SURGERY IN SEVERE OBESITY

Homocysteine is a sulfur-containing amino acid that is formed after the demethylation of methionine. High levels of plasma homocysteine have been proposed as a major and independent risk factor for cardiovascular disease. It is well known that obesity is also a modifiable and independent risk factor for cardiovascular disease. Extensive research has shown that weight loss produced by both traditional methods (dietary restriction/exercise) and gastric bypass surgery can improve several well known cardiovascular risk factors. As the rates of morbid obesity have been rapidly growing, the number of gastric bypass surgeries has also drastically increased, with Roux-en-Y gastric bypass (RNYGBP) surgery being the most common. While it is relatively well known that gastric bypass and weight loss improve many other risk factors for cardiovascular disease, the literature has been very limited regarding the effect of gastric bypass surgery on plasma homocysteine concentrations. The purpose of this study is to examine the effect of this surgery on the emerging cardiovascular disease risk factor of high plasma homocysteine. Participants were recruited from patients scheduled to undergo gastric bypass surgery at the Wake Forest University Baptist Medical Center General Surgery Clinic. Men and women were eligible for the study if they had a BMI ≥ 40.0 kg/m2 or ≥ 35.0 kg/m2 with an obesity related comorbidity, such as hypertension, dyslipidemia, or diabetes. Participants (n=19 female; age=45.7 (±8.8) years; BMI=54.4 (±7.2) kg/m2 had blood drawn prior to, and at 3 weeks, 3 months, 6 months, and 12 months post-surgery. Blood serum was analyzed for homocysteine, as well as vitamins B-12 and folate because these water-soluble B vitamins are determinants of serum homocysteine levels. One-way repeated measure ANOVA determined effect of the surgery on homocysteine over time. Weight loss was -7.8 (±1.5)% at 3 weeks, -17.7 (±2.7)% at 3 months, -26.0 (±4.0)% at 6 months, and -33.8 (±7.1)% at 12 months. Serum folate and vitamin B-12 did not significantly change from baseline to 12 months. Serum homocysteine levels were 10.5 (±3.6) μM/L at baseline, 11.8(±3.9) μM/L at 3 weeks, 11.4(±3.9) μM/L at 3 months, 11.7(±2.9) μM/L at 6 months, and 10.4 (±2.4) μM/L at 12 months. Serum homocysteine levels did not significantly change during the study. At baseline and throughout the course of the study, 95% of the participants had normal homocysteine levels. Change in homocysteine at twelve months was significantly negatively correlated to change in BMI as well as change in weight between baseline values and other visits. Results indicate that when vitamin status is controlled, Roux-en-Y gastric bypass surgery will not significantly alter homocysteine levels in morbidly obese patients.

Grantor dc:publisher

Wake Forest University

Year dc:date.issued

2009

Author dc:creator

• Blank, Brandon

• Homocysteine

Language dc:language.iso

en_US

Handle dc:identifier.uri

http://hdl.handle.net/10339/14916

OAI identifier oai:identifier

oai:wakespace.lib.wfu.edu:10339/14916