Anemia After Gastric Bypass: Still a Risky Business?

Authors: Eldo E. Frezza, MD, MBA, FACS, Amber Moreland, MSII


Morbid obesity is one of the most common causes of morbidity and mortality in the United States. In the next 20 years, 40% of the population will be obese with a body mass index (BMI) greater than 30. Operations for morbid obesity (BMI >35), such as Roux-en-Y gastric bypass (RYGBP), are becoming more popular. An awareness of the potential complications and side effects of these operations has increased along with the increase in the number of procedures performed. Nutritional problems have been observed and reported at length.1–4 One of the effects of this malnutrition is anemia.

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1. Love AL, Billett HH. Obesity, bariatric surgery, and iron deficiency: true, true, true and related. Am J Hematol 2008;83:403–409.
2. Folope V, Coeffier M, Dechelotte P. Nutritional deficiencies associated with bariatric surgery. Gastroenterol Clin Biol 2007;31:369–377.
3. Perlman SE, Reinhold RB, Nadzam GS. How do family practitioners perceive surgery for the morbidly obese? Surg Obes Relat Dis 2007;3:428–433.
4. Mizon C, Ruz M, Csendes A, et al. Persistent anemia after Roux-en-Y gastric bypass. Nutrition 2007;23:277–280.
5. Brethauer SA, Chand B, Schauer PR. Risks and benefits of bariatric surgery: current evidence. Cleve Clin J Med 2006;73:993–1007.
6. Shah M, Simha V, Garg A. Review: long-term impact of bariatric surgery on body weight, comorbidities, and nutritional status. J Clin Endocrinol Metab 2006;91:4223–4231.
7. Clements RH, Katasani VG, Palepu R, et al. Incidence of vitamin deficiency after laparoscopic Roux-en-Y gastric bypass in a university hospital setting. Am Surg 2006;72:1196–1204.
8. Mason ME, Jalagani H, Vinik AI. Metabolic complications of bariatric surgery: diagnosis and management issues. Gastroenterol Clin North Am 2005;34:25–33.
9. Vargas-Ruiz AG, Hernandez-Rivera G, Herrera MF. Prevalence of iron, folate, and vitamin B12 deficiency anemia alter laparoscopic Roux-en-Y gastric bypass. Obes Surg 2008;18:288–293.
10. Parkes E. Nutritional management of patients after bariatric surgery. Am J Med Sci 2006;331:207–213.
11. Smith CD, Herkes SB, Behrns KE, et al. Gastric acid secretion and vitamin B12 absorption after vertical Roux-en-Y gastric bypass for morbid obesity. Ann Surg 1993;218:91–96.
12. Schiegel DM, Maglinte DD. The blind pouch syndrome. Surg Gynecol Obstet 1982;155:541–544.
13. Evers BM. Small intestine, in Townsend CM, Beauchamp RD, Evers BM, et al (eds): Sabiston Textbook of Surgery: The Biological Basis of Modern Surgical Practice. Philadelphia, Elsevier Saunders, 2004, ed 17, pp 1323–1380.
14. Vettoretto N, Poiatti R, Ghilardi G, et al. Blind pouch syndrome secondary to gastrojejunostomy. Report of a case. Chir Ital 2006;58:263–266.
15. Wylezol M, Gluck M, Zubik R, et al. Biliopancreatic diversion in Poland. J Physiol Pharmacol 2005;58:117–126.
16. Fabry H, Hendrickx L, Van Hee R. Blind loop syndrome after biliopancreatic diversion: a diagnostic challenge. Obes Surg 2001;11:643–645.
17. Lee WJ, Yu PJ, Wang W, et al. Laparoscopic Roux-en-Y versus mini-gastric bypass for the treatment of morbid obesity: a prospective randomized controlled clinical trial. Ann Surg 2005;242:20–28.
18. Frezza EE, Wachtel MS. A simple venous thromboembolism prophylaxis protocol for patients undergoing bariatric surgery. Obesity 2006;14:1961–1965.
19. Marinella MA. Anemia following Roux-en-Y surgery for morbid obesity: a review. South Med J 2008;1024–1031.
20. Simon SR, Zemel R, Betancourt S, et al. Hematologic complications of gastric bypass for morbid obesity. South Med J 1989;82:1108–1110.