Background: We sought to identify the frequency and mechanisms of anemia after bariatric surgery in a bariatric surgery program at the Medical College of Wisconsin, (Milwaukee, WI). Anemia after bariatric surgery has often been attributed to iron deficiency, although an inflammatory component might be present, making the anemia after surgery mechanistically complex.Methods: The body mass index and hemoglobin (Hb), vitamin B-12 folate, iron, and ferritin levels were extracted from the records of 1125 patients for 4 years after Roux-en-Y gastric bypass. Anemia was defined using the World Health Organization criteria.Results: The mean body mass index. lib. and ferritin decreased after surgery. The body mass index decreased from 50.1 kg/m(2) (95% confidence interval [CI] 49.6-50.6) at baseline to 33.0 kg/m2 (95% CI 32.3-33.6) at 12 months and remained unchanged thereafter. The Hb level decreased from 13.4 g/dL (95% CI 13.3-13.5) to 12.8 (95% CI 12.6-13.1) and ferritin from 87.5 ng/mL (95% CI 75.2-99.7) to 55.4 (95% CI 42.9-68.0) at 24-48 months, and scrum iron increased from 68.4 mu g/dL (95% CI 66.8-70.0) to 82.8 (95% CI 76.4-88.7): all P values were <.01. Anemia was present in 12% (95% CI 10-14%) of patients at baseline and had increased to 23% (95% CI 16-30%) at 24-48 months. The changes in ferritin, Hb. and the percentage of patients with anemia were most pronounced in premenopausal women. Vitamin B,, and folate levels were unaffected.Conclusion: The baseline incidence of anemia was greater than expected and increased significantly after surgery. The percentage of those with anemia and low ferritin was most significant in premenopausal women: however, the overall iron bioavailability improved significantly with pronounced weight loss, suggesting a reduction in inflammation. These findings indicate that anemia after bariatric surgery cannot be explained on the basis of iron availability and suggest that other median isms. currently undefined, contribute to the development of anemia in these patients. (Surg Obes Relat Dis 2011:7: 151-156.) (C) 2011 American Society for Metabolic and Bariatric Surgery. All rights reserved.

Parathyroid hormone (Pth) maintains calcium homeostasis in hypovitaminosis D by resorption of calcium from bone. 30.2% of patients (pts) presenting for gastric bypass have secondary hyperparathyroidism, and are at risk of osteopenia after surgery due to malabsorption of vitamin D (Vit D) and calcium (Ca). Because hyperparathyroidism has deleterious effects on bone, we evaluated patients with elevated preoperative Pth levels for preoperative bone loss.

Bariatric surgery has become an important means to reduce obesity and its related morbidity. Bariatric surgeries in the US have increased from 14,000 in 1998 to 140,000 in 2004. Malabsorption and achlorhydria can complicate bariatric surgery and may lead to iron deficiency and anemia. In this setting, little is known about the prevalence and severity of anemia and the efficacy of oral iron replacement, a common part of post-surgical management. We reviewed the records at our institution of a large number (n=1125; 126 men; 999 women) of patients followed for up to 4 yrs post-procedure for the development of anemia and assessment of vitamin levels and iron stores.