Impact of limb length on nutritional status in one-anastomosis gastric bypass: 3-year results

Background: Bariatric metabolic surgery is a well-established treatment option associated with significant weight loss and an improvement of metabolic co-morbidities. However, the changes in gastrointestinal anatomy frequently result in nutritional deficiencies.

Objective: To evaluate the impact of biliopancreatic limb length in one-anastomosis gastric bypass (OAGB) on micronutrient and protein deficiencies.

Setting: University hospital, Austria.

Methods: All patients that were (1) undergoing OAGB between 2012 and 2014, and (2) had at least 3 postoperative follow-up visits were retrospectively analyzed. Systemic levels of parathyroid hormone, vitamins (A, D, E, and B12), folic acid, magnesium, calcium, iron, albumin, and ferritin were correlated to biliopancreatic limb length as follows: short limb (150 cm), intermediate limb (200 cm), and long limb (250 cm).

Results: A total of 155 patients fulfilled inclusion criteria (female/male: n = 111/44). OAGB led to a mean percent excess weight loss of 79.9 (±24.2) and a reduction of mean body mass index from 45.4 kg/m² (±6.1 kg/m²) at baseline to 30.2 kg/m² (±9.9 kg/m²). Preoperative deficiencies were seen in 25-hydroxy-vitamin D (93.8%), folic acid (27.6%), ferritin (4.1%), vitamin A (5.5%), and vitamin B12 (2.3%). In patients with long limb, systemic folic acid levels were significantly lower after 24 months postoperatively compared with short and intermediate limb (P < .05). No difference was observed for vitamin D, A, E, B12, and iron and no patient suffered from severe protein malnutrition.

Conclusion: Nutritional deficiencies were common after OAGB without severe deficiencies in biliopancreatic limb lengths ranging from 150 to 250 cm. A trend can be observed with more pronounced deficiencies with intermediate and long limb lengths without significant differences for most micronutrients.