Gastric bypass is not associated with protein malnutrition in morbidly obese patients.
BACKGROUND
Patients undergoing bariatric surgery with a gastric bypass lose about 66% of excess weight. Although this procedure induces weight loss, it is unknown whether it leads to protein malnutrition, which is studied here.


METHODS
One hundred ten obese patients (body mass index, 47.9 +/- 8.6 kg/m(2)) undergoing gastric bypass had a measurement of plasma albumin and transthyretin (formerly prealbumin) and a calculation of nutritional risk index (NRI) before and throughout the 2 years following the surgery.


RESULTS
All but five patients lost more than 15% of initial weight; the mean loss of excess weight was 65.2 +/- 26.4% at 2 years. Plasma concentrations of albumin and transthyretin decreased after surgery, but while albumin returned to initial values after 12 months, transthyretin remained low. Only one patient had an albumin below 30 g/l; another one had a transthyretin lower than 110 mg/l. All NRI scores were lower than 83.5 (62 +/- 5, ranging 44-70), qualifying patients for severe malnutrition.


CONCLUSIONS
Malnutrition is difficult to diagnose in obese patients undergoing surgery. The large weight loss is most often not associated with protein malnutrition. Whether gastric bypass induces protein malnutrition remains to be established.
Ritz
Patrick
P
Inserm UMR 694, Angers, France. Patrick.ritz@wanadoo.fr
Becouarn
Guillaume
G
Douay
Olivier
O
Sallé
Agnès
A
Topart
Philippe
P
Rohmer
Vincent
V
D000328:Adult; D005260:Female; D015390:Gastric Bypass / Q000009:adverse effects*; D006801:Humans; D008297:Male; D044342:Malnutrition / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D009752:Nutritional Status; D009767:Obesity, Morbid / Q000601:surgery*; D011228:Prealbumin / Q000032:analysis; D012709:Serum Albumin / Q000032:analysis; D015431:Weight Loss
D011228:Prealbumin; D012709:Serum Albumin