The study also revealed a trend towards higher risk in older patients, especially those over 50 years old. The oldest group (65+ years) had a mortality rate of about 0.22 percent compared to no deaths in youngest group (18-30 years). Older patients had a significantly higher complication rate (12.82% vs. 4.89%), more than twice the ICU admissions (11.07% vs. 4.93%), a hospitalization period that was longer by a full day (3.47 vs. 2.37 days) and costs that were higher by almost $4,000 ($17,260 vs. $13,637).

Across all demographics, disease severity was found to have a significant impact on gastric bypass outcomes. For those with the highest severity, compared to those with the lowest, the complication rate was 15 times higher (51.33% vs. 3.23), the mortality rate was 1.57 percent versus 0.01 percent, and costs were $20,000 higher ($13,630 vs. $33,286). Researchers suggest that different levels of disease severity within the demographic groups may help account for differences in outcomes. For example, higher illness severity in males may be a reason for gender differences in post-surgery outcomes and higher illness severity among African-American patients may help explain poor outcomes in this group. They noted more research into the causes of these disparities is needed.

"Despite the differences in outcomes that we see in some demographic groups, laparoscopic gastric bypass procedures have been shown to be safe with excellent outcomes across race, gender and age," said Dr. Tiwari. "What's important to note is that many patients may delay medical intervention, which may lead to higher levels of illness severity. Patients should seek treatment earlier for the best chance at favorable post-surgery outcomes."

People who are morbidly obese are generally 100 or more pounds overweight, have a BMI of 40 or more, or a BMI of 35 or more with an obesity-related disease, such as Type 2 diabetes, heart disease or sleep apnea. According to the ASMBS, more than 15 million Americans are considered morbidly obese and in 2009 an estimated 220,000 people had some form of bariatric surgery. The most common methods of bariatric surgery are laparoscopic gastric bypass and laparoscopic adjustable gastric banding.

SOURCE American Society for Metabolic & Bariatric Surgery (ASMBS)