Clinicians may find this scoring system helpful when counseling patients considering bypass surgery.
One deterrent to gastric bypass surgery is the relatively high incidence of perioperative complications — some life-threatening — in this patient population. Earlier this year, researchers described an "obesity surgery mortality risk score," developed at a single institution with 2075 patients (Surg Obes Relat Dis 2007; 3:134). Now, the researchers have validated their scoring system using gastric bypass surgery databases at four other institutions (involving about 1000 patients at each center). Open and laparoscopic procedures were considered together.
The scoring system assigns one point to each of
five preoperative factors: body-mass index 
50 kg/m2, male sex,
hypertension, risk factors for pulmonary embolism (including previous
thromboembolic disease), and age 45. Nearly half the patients were at
low risk (scores of 0 or 1), nearly half were at intermediate risk (scores of 2
or 3), and only 3% were at high risk (scores of 4 or 5). Ninety-day mortality
after gastric bypass surgery was 0.2%, 1.1%, and 2.4% in the three risk groups,
respectively.
Comment: This scoring system may be useful for clinicians discussing the merits and possible complications of gastric bypass surgery with patients. Whether the results would apply to centers with lower volume and less experience is unclear. Moreover, the mortality risk calculation for the high-risk group had a wide confidence interval, given the small number of patients (125) in that group.
Published in Journal Watch General Medicine October 11, 2007
DeMaria EJ et al. Validation of the obesity surgery mortality risk score in a multicenter study proves it stratifies mortality risk in patients undergoing gastric bypass for morbid obesity. Ann Surg 2007 Oct; 246:578.