Gastric Bypass in Chronic Renal Failure and Renal TransplantCenter for Surgical Weight Loss, University of Cincinnati, Cincinnati, Ohio Correspondence: J. Wesley Alexander, University of Cincinnati, 2123 Auburn Avenue, MOB Suite 315, Cincinnati, OH 45219. Electronic mail may be sent to jwesley.alexander{at}uc.edu. Background: Morbid obesity has reached epidemic proportions in developed nations worldwide, causing considerable mortality and increased healthcare expenditures. The use of gastric bypass surgery to achieve weight loss in morbidly obese patients with chronic renal failure (CRF) and postrenal transplant patients has not been studied adequately. Methods: Forty-one patients with different stages of CRF (25 already receiving dialysis) underwent a gastric bypass (GBP), and an additional 10 patients underwent a GBP after becoming morbidly obese after transplantation. Results: Of the 41 patients with CRF, 5 stabilized or resolved their kidney disease and 9 underwent successful transplantation. These patients had a loss of 68% excess body mass index (BMI) by 12 months after GBP. Of the 10 patients with GBP after transplant, the mean loss of excess BMI was 70.5%. There were no in-hospital or 30-day mortalities, but 8 of the 51 patients died from 112 to 2869 days postoperatively, 7 from cardiac or vascular events and 1 from an automobile accident. This compares with an approximate 10% mortality per year for patients receiving dialysis. Comorbid conditions associated with morbid obesity improved in all patients and permitted eligibility for transplantation. Conclusions: GBP for massive weight reduction in morbidly obese renal failure and transplant patients leads to a reduction in comorbid conditions that are associated with an increased risk for cardiovascular deaths. There was no operative mortality in this series, and all but 1 death were related to previously existing disease of the cardiovascular system.
Obesity has become an increasingly important cause of morbidity and
mortality worldwide. In the United States, >300,000 deaths per year are
caused by obesity and its related
comorbidities.1 This
is associated with more than $117 billion per year in healthcare
costs.2 Years of
life lost because of morbid obesity is as much as 20 years for African
American men with a body mass index (BMI)
Bariatric surgery has emerged as the most effective treatment for massive and sustained weight loss in patients with morbid obesity. More than 90% of the associated comorbid conditions are improved or resolved completely with gastric bypass (GBP), which has become the gold standard for bariatric surgical procedures. Very few studies are currently available regarding the improvement of survival in patients with GBP compared with those that do not receive bariatric surgery, but 1 large study from Canada reported a reduction of approximately 89% over a 5-year period in patients receiving bariatric surgery compared with those who do not.5 The benefit of GBP has been extended to patients with increasingly complex comorbidities, some of which have been felt to be a contraindication to surgery. We recently reported our initial experience with this procedure in 30 patients with chronic renal failure (CRF) or kidney transplant.6 The current report documents an additional 2-year follow-up and includes 18 more patients, representing the majority of the world's published experience.
Three groups of patients were analyzed: 32 patients with CRF who had GBP without transplant, 9 patients who had a GBP and then a kidney transplant, and 10 patients who had a prior transplant with a subsequent GBP because of significant weight gain. No patient referred for a GBP was denied according to the severity of their illness. A standard GBP modified for limb length, as previously described,6 was used for all patients. One GBP surgery was performed laparoscopically and 31 by an open procedure using double-layer hand-sewn anastomosis, which is associated with fewer serious complications. The first GBP in our series was performed March 16, 1993. Only 1 patient has been lost to follow-up. This study was approved by the institutional review board.
The median hospital stay was 4 days for the patients with CRF, 5 days for the patients with GBP then transplant, and 6 days for patients with transplant then GBP. This was longer than our median stay of 2 days because of the complexity of their disease and the need for dialysis in some patients. No patient required blood transfusions related to the surgery, and there were no surgical leaks or splenic injuries. A technique was used in which antibiotics were infused into the wound as previously described.7 One patient developed wound separation and secondary infection after the sutures were prematurely removed, but there were no other wound infections that started in the subcutaneous tissues. Eight patients have died in this series during the 13-year follow-up, all 3 months or more after GBP as described in Table 1. One-year patient survival was 92%.
CRF Patients
GBP and Then Transplant
Transplant and Then GBP Ten patients who had a transplant became morbidly obese afterwards and developed secondary complications. Their mean age was 44 years. All were receiving immunosuppression and 9 were taking corticosteroids. GBP occurred on average 5.3 years after transplant. Changes in BMI for up to 5 years are shown in Figure 3.
Resolution or Stabilization of CRF Five patients experienced resolution or stabilization of their CRF after GBP. Because of the particular interest in these cases, these patients are discussed individually. Patient 1 is a 42-year-old female with chronic membranous glomerulonephritis diagnosed by biopsy. She had proteinuria consistently >300 mg/L and had unsuccessful treatment with prednisone. Her BMI was 53.3 kg/m2 at the time of GBP on August 26, 1999, but dropped to a 1-year postoperative BMI of 32.3 kg/m2 and a 5-year postoperative BMI of 29 kg/m2. The proteinuria resolved completely, and repeat biopsy showed resolution of the glomerulonephritis. Her creatinine has remained stable at 0.7 mg/dL since her bypass. Patient 2 is a 48-year-old woman who had a GBP on January 16, 2003. Her BMI was 49.4 kg/m2, and she had hypertension, diabetes, hyperlipidemia, and sleep apnea. She had heavy proteinuria, with a diagnosis of focal segmental glomerulosclerosis. Her BMI had dropped to only 37.9 kg/m2 by 3 years post-GBP, but her creatinine has stabilized at 1.5 mg/dL, which is at the level when she was first diagnosed with renal insufficiency.
Patient 3 is a 21-year-old woman with a BMI of 44.5 kg/m2 when she underwent GBP surgery in August 2003. At that time, she had biopsy-proven glomerulonephritis, and her creatinine was 1.7 mg/dL. She continued to have proteinuria, but her creatinine dropped to 0.6 mg/dL at the end of the second year, associated with a drop in BMI to 28.4 kg/m2. Patient 4 is a 47-year-old woman who underwent GBP on August 5, 2003. Her initial BMI was 51.0 kg/m2, and creatinine was 2.6 mg/dL. With a reduction in BMI to 34.5 at 2 years postoperatively, her serum creatinine level had dropped to 2.2 mg/dL, and creatinine clearance increased from 23 to 35 mL/min. The original diagnosis was diabetic nephropathy. Patient 5 is a 25-year-old woman with an initial BMI of 39 kg/m2 who underwent GBP in November 2004. Her original diagnosis was glomerulonephritis, and she had been receiving dialysis for 9 months. Four months after her GBP, she was able to discontinue dialysis, and her creatinine is now stable at 5.1 mg/dL. She recently underwent an abdominoplasty, and her current BMI is 25 kg/m2. It is anticipated that she will eventually need preemptive transplantation.
Effects of Morbid Obesity on Outcome Patients requiring dialysis for CRF have been noted to have a paradoxic relationship between weight and mortality.8 This was first suggested by the Diaphane Collaborative Study in 1982.9 Subsequent studies have also shown that overweight and obese dialysis patients had a significantly greater 12-month survival than those of normal weight10 and suggest that for every unit increase in BMI, the relative risk for mortality was reduced by 6%. More striking, increasingly underweight patients had the highest mortality, and a loss in BMI in obese patients receiving dialysis was associated with increased mortality. Johansen et al11 examined data for 418,055 patients beginning dialysis between April 1, 1995, and November 1, 2000. A high BMI (highest reported  37) had increased survival over the
2-year average follow-up. Kalantar-Zadeh et
al12 reviewed the
subject in 2005 and also concluded that a high BMI was associated with
improved survival. This paradox seemed to be related primarily to improved
nutrition status. However, additional reports did not find a positive
influence of high BMI on 2-year
survival.13
Contrary findings were also shown by Caravaca et
al,14 who studied
376 patients with advanced CRF, not yet receiving dialysis. Obese patients
(BMI 30 k/m2) had a worse survival, notably in patients without
significant comorbidities. Unfortunately, most studies have been relatively
short term, and only a small number of patients with BMI >35
kg/m2 have been studied.
The paradoxic beneficial effect of obesity in dialysis patients has not
been found to apply to transplant patients. The most extensive study on this
topic was presented by Meier-Kriesche et
al,15 who analyzed
the data from the United States Renal Data System (USRDS) database between
1988 and 1997 involving 51,927 adult transplant recipients. In their study,
the relative risk for graft loss was approximately 1.4 in patients with a BMI
>36 kg/m2. Similar risk ratios were found for death censored
graft loss (RR = 1.45 for BMI
From the current data, it seems clear that extremely obese patients fare better with a transplant compared with similar patients who continue to receive dialysis.19 It is also clear that the comorbid conditions in dialysis patients related to cardiovascular disease can be markedly decreased by GBP, to a similar amount that occurs in morbidly obese patients who are not receiving dialysis.22
Resolution and Stabilization of Renal Function
Bariatric Surgery in Preparation for Transplantation One of the major reasons for performing a GBP in morbidly obese dialysis patients is to improve their comorbidities and prepare them for transplantation. Meier-Kriesche et al29 provided clear evidence that progression of vascular disease is ameliorated by kidney transplantation. By reversing the comorbid conditions leading to cardiovascular disease, it is felt that GBP will achieve the same reduction in risk as for nontransplant patients. However, this remains to be verified by larger studies. Pischon and Sharma30 compared overall reported mortality in obese compared with nonobese transplant patients. The 5-year mortality in obese patients was 23%–45% vs 10%–11% in nonobese patients, and the mortality was caused primarily by an increase in cardiac events. Infections, wound complications, and delayed graft function were also more common in obese vs nonobese patients, but acute rejection was not different. In their review, hypertension, dialysis, death with a functioning graft, and worsening of long-term allograft survival were all higher in obese patients.
Srinivas and
Meier-Kriesche31
concluded that it was unclear whether dialysis patients should be made to lose
substantial amounts of weight before kidney transplantation. They did
acknowledge, however, that obesity clearly had adverse effects on outcome
after transplantation. Data provided by UNOS indicated that 5-year patient
survival was 80% for patients with BMI In our series of patients, nutrient deficiencies were not limiting, although nutrition modifications needed to be made for dialysis, transplantation, and GBP. Protein supplementation is sometimes difficult in GBP because of loss of appetite, aversion to certain protein-containing foods, and distasteful protein supplements. In dialysis patients with a GBP, particular attention should be given to supplementation with calcium with vitamin D, water-soluble vitamins, and iron. Careful monitoring can easily prevent significant dietary deficiencies. It is clear that patients with GBP may have changes in the pharmacokinetics of immunosuppressive drugs as we have previously reported (unpublished data). However, immunosuppression is usually driven by drug levels, making this less important. The literature is silent on the pharmacokinetics of most other drugs after GBP. We conclude that GBP is a highly effective procedure for achieving long-lasting weight loss and resolution of serious comorbid conditions in dialysis/transplant patients with an acceptable morbidity/mortality. Nutrition deficiencies occur infrequently with appropriate supplements. Weight loss after GBP also seems to stabilize or improve renal disease in some patients, suggesting additional benefits for GBP early in CRF. Early GBP may also allow preemptive transplantation.
Nutrition in Clinical Practice, Vol. 22, No. 1,
16-21 (2007) This article has been cited by other articles:
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Materials and Methods
Results
