Garrido-Sánchez L et al. (2008) Improved carbohydrate metabolism after bariatric surgery raises antioxidized LDL antibody levels in morbidly obese patients. Diabetes Care 31: 2258–2264

Oxidative stress increases oxidation of LDL and, thereby, influences the pathogenesis of diabetes mellitus. Garrido-Sánchez et al. conducted a study to determine whether the improvements in carbohydrate metabolism brought about by bariatric surgery affect levels of oxidized LDL (oxLDL) and antibodies against oxLDL.

Of the 73 morbidly obese patients enrolled in this study, 21 had a fasting glucose level suggestive of type 2 diabetes mellitus (≥7.0 mmol/l). At baseline, oxLDL levels were significantly higher and levels of IgM antibodies against oxLDL significantly lower in the 21 morbidly obese patients with diabetes mellitus than in 11 healthy, nonobese individuals with normal or mildly impaired fasting glucose (P <0.05).

Levels of both IgM and IgG antibodies against oxLDL had significantly increased from baseline values by 7 months after bariatric surgery in the morbidly obese patients with diabetes mellitus (P <0.05 for both comparisons), which was reflected in a significant drop in oxLDL levels (P <0.05). Improved carbohydrate metabolism (as demonstrated by intravenous glucose tolerance test results) was the main factor associated with the changes in the levels of antibodies against oxLDL and oxLDL in this group of patients.

The authors suggest that improved glycemic control after bariatric surgery might have a beneficial effect on the response to oxidative stress in morbidly obese patients with diabetes mellitus.