WASHINGTON (FRONTLINE MEDICAL NEWS) – Readmissions after bariatric surgery are significantly higher among black patients than among whites.

The reasons aren’t entirely clear, but since long-term morbidity and mortality are equivalent, they are probably more related to socioeconomics than clinical factors, Matthew Whealon, MD, said at the annual clinical congress of the American College of Surgeons.

“I think they are multifactorial,” said Dr. Whealon of the University of California, Irvine. “Some of it may be related to comorbidities, but other factors could be socioeconomic status, insurance status, access to primary care and follow-up care, even home support systems and patient expectations after surgery. I think it’s incumbent upon us to try and identify some of these risk factors and address them before surgery to reduce this disparity in readmissions.”

Dr. Whealon looked at morbidity, mortality, and readmission rates among almost 62,000 bariatric surgeries that were included in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database. These were almost equally split between Roux-en-Y and vertical sleeve gastrectomy. About 80% of each cohort were white and 20% were black.

Black patients undergoing Roux-en-Y bypass were significantly younger (43 vs. 45 years), and more often women (86% vs. 78%). They also had significantly higher body mass index than did white patients (48 vs. 46 kg/m2). More black individuals had a BMI of 50 kg/m2 or higher.

There were no significant differences in the severity of comorbidities. About 70% of each group had severe comorbidities as classified by the American Anesthesiologists Society risk assessment profile.

However, those comorbidities were different. Among black patients, steroid use, heart failure, hypertension, and end-stage renal disease were significantly more common. Among white patients, chronic obstructive pulmonary disease and bleeding disorders were more common.

There were no differences in 30-day mortality (less than 1% of each group); serious morbidity (3%) or any morbidity (5%); length of stay (2.4 days); or reoperation (2.6%).

However, readmissions were significantly more likely among black patients (8% vs. 5.6%). This translated to a 29% increased risk of readmission (OR 1.29).

Compared to whites, blacks who had a laparoscopic vertical sleeve gastrectomy were also significantly younger (42 vs. 45 years); more often women (87% vs. 76%); and heavier (BMI 47 vs. 45 kg/m2). Again, they were more likely to have a BMI of more than 50 kg/m2 (28% vs. 21%).

Significantly more were in the ASA class 3 of severe comorbidities (70% vs.66%). There were also differences in the comorbidities, with blacks more likely to have heart failure, hypertension, and end-stage renal disease, and whites more likely to have diabetes, smoking, dyspnea, and chronic obstructive pulmonary disease.

Among these patients, 30-day mortality was not different (less than 1%). Serious morbidity was also similar (about 2%), as was any morbidity (about 3%). The reoperation rate was the same (1.2%).

Length of stay was longer among black patients but this was not clinically significant, Dr. Whealon said: It still hovered right around 2 days.

But readmissions were significantly more common among blacks (5% vs. 3%). This difference translated to a 35% increased risk of readmission (odds ratio 1.35).

The nature of the NSQIP data makes it impossible to tease out any other factors that might have contributed to this finding. However, Dr. Whealon said, the equivalent findings on morbidity and mortality are very encouraging and represent a big improvement.

“We have done very well in driving down morbidity and mortality among these patients. Mortality rates are one tenth of what we were seeing a decade ago.”

This change hasn’t been well documented yet because many of the large studies showing racial and ethnic mortality disparities include data drawn from open bariatric surgery, which has been almost completely abandoned in favor of the much safer laparoscopic approaches.

Dr. Whealon had no financial disclosures.

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