Are vitamin B12 and folate deficiency clinically important after roux-en-Y gastric bypass?

Although iron, vitamin B12, and folate deficiency have been well documented after gastric bypass operations performed for morbid obesity, there is surprisingly little information on either the natural course or the treatment of these deficiencies in Roux-en-Y gastric bypass (RYGB) patients. During a 10-year period, a complete blood count and serum levels of iron, total iron-binding capacity, vitamin B12, and folate were obtained in 348 patients preoperatively and postoperatively at 6-month intervals for the first 2 years, then annually thereafter. The principal objectives of this study were to determine how readily patients who developed metabolic deficiencies after Roux-en-Y gastric bypass responded to postoperative supplements of the deficient micronutrient and to learn whether the risk of developing these deficiencies decreases over time. Hemoglobin and hematocrit levels were significantly decreased at all postoperative intervals in comparison to preoperative values. Moreover, at each successive interval through 5 years, hemoglobin and hematocrit were decreased significantly compared to the preceding interval. Folate levels were significantly increased compared to preoperative levels at all time intervals. Iron and vitamin B12 levels were lower than preoperative measurements and remained relatively stable postoperatively. Half of the low hemoglobin levels were not associated with iron deficiency. Taking multivitamin supplements resulted in a lower incidence of folate deficiency but did not prevent iron or vitamin B12 deficiency. Oral supplementation of iron and vitamin B12 corrected deficiencies in 43% and 81% of cases, respectively. Folate deficiency was almost always corrected with multivitamins alone. No patient had symptoms that could be attributed to either vitamin B12 or folate deficiency Conversely, many patients had symptoms of iron deficiency and anemia. Lack of symptoms of vitamin B12 and folate deficiency suggests that these deficiencies are not clinically important after RYGB. Conversely, iron deficiency and anemia are potentially serious problems after RYGB, particularly in younger women. Hence we recommend prophylactic oral iron supplements to premenopausal women who undergo RYGB.

Prophylactic iron supplementation after Roux-en-Y gastric bypass: a prospective, double-blind, randomized study.

OBJECTIVE: To determine whether prophylactic oral iron supplements (320 mg twice daily) would protect women from iron deficiency and anemia after Roux-en-Y gastric bypass. DESIGN: Prospective, double-blind, randomized study in which 29 patients received oral iron and 27 patients received a placebo beginning 1 month after Roux-en-Y gastric bypass. SETTING: Tertiary care medical center. PATIENTS AND INTERVENTIONS: Complete blood cell count and serum levels of iron, total iron binding capacity, ferritin, vitamin B12, and folate were determined preoperatively and at 6-month intervals postoperatively in 56 menstruating women who had Roux-en-Y gastric bypass. MAIN OUTCOME MEASURE: Incidence of iron deficiency and other hematological abnormalities in each treatment group. RESULTS: Hemoglobin, hematocrit, and vitamin B12 levels were significantly decreased compared with preoperative values in both groups. Conversely, folate levels increased significantly over time in both groups. Oral iron consistently prevented development of iron deficiency in the iron group. Ferritin levels did not change significantly in the iron group. However, in placebo-treated patients, ferritin levels 2 years postoperatively were significantly decreased compared with preoperative levels. There was no difference in the incidence of anemia between the 2 groups. However, the incidence of microcytosis was substantially greater (P=.07) in placebo-treated than iron-treated patients. CONCLUSIONS: Prophylactic oral iron supplements successfully prevented iron deficiency in menstruating women after Roux-en-Y gastric bypass but did not consistently protect these women from developing anemia. On the basis of these results we now routinely recommend prophylactic iron supplements to menstruating women who have Roux-en-Y gastric bypass.

Weight loss and dietary intake after vertical banded gastroplasty and Roux-en-Y gastric bypass.

OBJECTIVE: The purpose of this study was to learn whether preoperative eating habits can be used to predict outcome after vertical banded gastroplasty (VBG) and Roux-en-Y gastric bypass (RYGB). BACKGROUND SUMMARY: Several independent randomized and sequential studies have reported significantly greater weight loss after RYGB in comparison with VBG. Although the mechanism responsible for weight loss after both procedures is restriction of intake rather than malabsorption, the relationships between calorie intake, food preferences, and postoperative weight loss are not well defined. METHODS: During the past 5 years, 138 patients were prospectively selected for either VBG or RYGB, based on their preoperative eating habits. All patients were screened by a dietitian who determined total calorie intake and diet composition before recommending VBG or RYGB. Thirty patients were selected for VBG; the remaining 108 patients were classified as "sweets eaters" or "snackers" and had RYGB. Detailed recall diet histories also were performed at each postoperative visit. RESULTS: Early morbidity rate was zero after VBG versus 3% after RYGB. There were no deaths. Mean follow-up was 39 +/- 11 months after VBG and 38 +/- 14 months after RYGB. Mean weight loss peaked at 74 +/- 23 lb at 12 months after VBG and 99 +/- 24 lb at 16 months after RYGB (p < or = 0.001). Twelve of 30 VBG patients lost > or = 50% of their excess weight versus 100 of 108 RYGB patients (p < or = 0.0001). Milk/ice cream intake was significantly greater postoperatively in patients who underwent VBG versus patients who underwent RYGB after 6 months (p < or = 0.003), whereas solid sweets intake was significantly greater after VBG during the first 18 months postoperatively (p < or = 0.004). Revision of VBG was performed in 6 of 30 patients (20%) for complications or poor weight loss, whereas only 2 of 108 patients who underwent RYGB required surgical revisions (p < or = 0.001). CONCLUSIONS: These data show that VBG adversely alters postoperative eating behavior toward soft, high-calorie foods, resulting in problematic postoperative weight loss. Conversely, RYGB patients had significantly greater weight loss despite inferior preoperative eating habits. The high rate of surgical revision in conjunction with inconsistent postoperative weight loss has led us to no longer recommend VBG as treatment for morbid obesity.

Long-limb gastric bypass in the superobese. A prospective randomized study.

This study was designed to determine whether greater diversion of bile and pancreatic secretions away from the functional gastrointestinal tract would produce greater weight loss in superobese patients (greater than or equal to 200 pounds overweight) in comparison with conventional Roux-en-Y gastric bypass (RYGB). During the past 7 years, two modifications of RYGB were prospectively compared in 45 superobese patients: RYGB-1, in which the length of defunctionalized jejunum measured 75 cm, and RYGB-2, in which the defunctionalized jejunum measured 150 cm. Respective mean preoperative weight/body mass indexes were 393 pounds/63.4 for 22 RYGB-1 patients and 404 pounds/61.6 for 23 RYGB-2 patients. Two patients (5%) had nonfatal early complications. There were six late incisional hernias. There were no cases of protein deficiency, hepatic dysfunction, or diarrhea after operation. Mean follow-up was 43 +/- 17 months. Postoperative weight loss in pounds and daily calorie intake were compared at 6-month intervals. Weight loss stabilized by 24 months at a mean 50% excess weight lost in RYGB-1 patients and 64% excess weight lost in RYGB-2 patients. Nineteen of 23 RYGB-2 patients achieved at least 50% excess weight lost versus 11 of 22 RYGB-1 patients (p less than or equal to 0.03). Weight loss was significantly greater at 24 through 36 months in RYGB-2 versus RYGB-1 patients (p less than 0.02). There was no significant difference in either calorie intake or incidence of iron and vitamin B-12 deficiency between the two groups. These data show that gastric restriction and biliopancreatic diversion without intestinal exclusion resulted in significantly greater weight loss than conventional RYGB but did not cause additional metabolic sequelae or diarrhea. This long-limb modification of Roux-en-Y gastric bypass is a safe and effective procedure in patients who are 200 pounds or more overweight.

Multivitamin prophylaxis in prevention of post-gastric bypass vitamin and mineral deficiencies.

One hundred forty patients were followed for a mean 24.2 months after gastric bypass. Postop multivitamin (MV) prophylaxis was recommended for all patients and 90 of 140 patients (64 percent) were regularly compliant. Deficiencies in iron, vitamin B-12 or folate were recognized in 88 of 140 patients (63 percent). Thirty of 45 patients (67 percent) with iron deficiency developed anemia. Forty-three of the 52 patients who did not have deficiencies were regularly taking MV vs 47 of 88 patients who developed deficiencies (P less than 0.001). MV prophylaxis was successful in preventing folate (P less than or equal to 0.05) and vitamin B-12 deficiencies (P less than or equal to 0.02) but did not prevent development of iron deficiency or subsequent anemia. There was no correlation between taking prescribed supplements and resolution of either iron deficiency of anemia. B-12 and folate supplements corrected deficiencies in 73 percent of cases. We conclude that oral MV prophylaxis is useful in preventing folate and B-12 deficiency after gastric bypass. Additional prophylactic iron supplements should be provided for women to prevent iron deficiency and associated anemia.

Serum lipids after gastric bypass surgery for morbid obesity.

Thirty-eight of 151 consecutive patients (25 percent) undergoing bypass surgery for morbid obesity had increased serum levels of total cholesterol (TC), triglycerides (TG) or both preoperatively. Ten patients had isolated TC elevation, six had isolated TG elevation and 22 had both TC and TG elevation. High density lipoprotein-cholesterol (HDL-C) levels were subnormal in 28 of the 38 patients (74 percent). Fasting lipid profiles were determined in the 38 hyperlipidemic patients at 6-month intervals postoperatively. Mean follow-up period was 29 months. By 6 months postop, patients had a greater than or equal to 20 percent mean reduction in TC and greater than or equal to 50 percent mean reduction in TG which were significant in comparison with preop levels and correlated with weight loss (P less than or equal to 0.05). Mean HDL-C levels had increased significantly vs. preop levels by 12 months postop (P less than 0.05). Lipid profiles became normal in 32 of the 38 patients (84 percent). Improvements in lipid profile were sustained in all patients with satisfactory weight loss but regressed after 12 months in patients who did not lose greater than or equal to 50 percent of their excess weight. These results suggest that abnormal serum lipid profiles can be permanently improved with sustained weight loss after gastric restriction surgery for morbid obesity.

Changes in eating behavior after horizontal gastroplasty and Roux-en-Y gastric bypass.

Postoperative changes in eight dietary variables were compared at 6-mo intervals over 24 mo in 53 horizontal-gastroplasty (HGP) and 51 Roux-en-Y gastric-bypass (RYGB) patients; the variables included 1) calorie intake; percent intake of 2) protein, 3) carbohydrate, and 4) fat; 5) sweets and high-calorie beverages (SWS) and 6) milk and ice cream (MIC) as percent of calories; and 7) high-calorie liquids (HCL) and 8) nonliquid sweets (NLS) as percentage of dietary sugar. Weight and calorie intake were significantly less after RYGB than after HGP after 6 mo (p less than or equal to 0.01). Protein intake was significantly increased at all intervals after RYGB and at 6 and 12 mo after HGP (p less than 0.05). After RYGB, intakes of SWS, MIC, and HCL were significantly decreased at all intervals (p less than 0.05). SWS and MIC consumption was also significantly less after RYGB than after HGP (p less than or equal to 0.05). Decreased SWS and MIC consumption in RYGB patients suggests that food-preference differences are partially responsible for the lower calorie intake and greater weight loss after RYGB than after HGP.

The dilemma of outcome assessment after operations for morbid obesity.

Outcome of 56 patients who underwent horizontal gastroplasty (HGP) and 126 who underwent Roux-en-Y gastric bypass (RYGB) was assessed at 18 months postoperatively according to three definitions of successful weight loss; also, outcome was evaluated in the context of amelioration of obesity-related medical problems. Outcome definitions included the following: I, loss of 25% or more of preoperative weight; II, loss of 50% or more of excess weight; III, loss to within 50% of ideal body weight. To evaluate the impact of preoperative weight on success rate, patients were divided into two weight groups: "morbidily" obese patients, who were 100 to 199 pounds overweight (n = 146), and "super"-obese patients who were 200 pounds or more overweight (n = 36). Weight loss was significantly greater with RYGB versus HGP by each of the three definitions of success. Medical problems either improved or resolved with weight loss in 95% of cases. There were statistically significant differences in success rate depending on outcome definition in both HGP and RYGB patients. Success rate ranged from zero in super-obese HGP patients by Definition III to 97% in super-obese RYGB patients by Definition I. Although super-obese patients lost more pounds than the lighter morbidly obese patients, a significantly lower number of super-obese patients lost within 50% of ideal weight. Super-obese patients must lose more weight to reduce their actuarial risk. These results show that the definition of successful outcome may significantly influence the overall success rate in a large series of bariatric surgical patients.

Diagnosis-related group impact of nutrition support in cardiac surgery patients.

We studied the diagnosis-related groups (DRG) impact of nutrition support on 80 consecutive cardiac surgery patients operated upon during a 6-month period. Six of 80 patients were nutritionally depleted preoperatively. Seven received postoperative supplemental nutrition, all of whom had major postoperative complications. Patients were arbitrarily placed into three outcome groups: group I consisted of seven patients who received postoperative nutrition support; group II included 38 patients who received no nutrition support and did not develop complications; Group III consisted of 35 patients who received no nutrition support but developed postoperative complications. All group I patients were length of stay (LOS) outliers. Group I patients were significantly older than groups II and III (p less than 0.0003) and had a significantly longer average length of stay (ALOS) (p less than 0.001), ALOS in SICU (p less than 0.0001) and greater incidence of both septic complications (p less than 0.02) and mortality (p less than 0.02). Nutrition support in cardiac surgery patients warrants special DRG consideration in light of the significantly increased hospitalization and resource utilization as compared with all other patients in cardiac surgery.