Gastric stapling for
morbid obesity has been popularized, in part, because of an apparent lack of metabolic sequelae. Of our series of prospectively studied
gastric bypass patients, 74 patients have been followed for more than 1 year.
Anemia developed in more than one-third of the patients. Nearly two-thirds of the patients developed decreased levels of
vitamin B12, and other abnormalities were commonly seen (
folate, 38%;
iron, 49%;
potassium, 56%). While prompt recognition and treatment has prevented development of a clinical deficiency syndrome in most patients, 12 per cent became anemic most likely because of
micronutrient deficiency related to the bypass. More than 10,000 gastric restriction operations are carried out for
morbid obesity each year in this country. Previous reports of
thiamine deficiency-related neurologic sequelae, immune
paralysis, and marrow suppression, together with the
micronutrient deficiencies and
anemia herein reported make long-term frequent metabolic assessment of these patients essential.