Obese patients with private health insurance lose much more weight than those covered by Medicare or Medicaid after having gastric bypass surgery.
Researchers looked at 750 patients who had undergone the procedure and found those insured by the federal programs lost 57-percent of their excess weight.
In comparison, patients with private health coverage lost 82-percent of their extra weight.
Dr. John Morton worked with the Stanford University School of Medicine team that conducted the study and presented the findings at the Digestive Disease Week meeting in Chicago.
He said they also found the Medicare patients had more weight to lose than those with private insurance.
He said the Medicare patients were also more likely to be depressed, have high blood pressure, heart disease, diabetes and other health problems, so they might need extra exercise and nutrition support to succeed.
The Medicare group had a higher complication rate, but no deaths were reported.
Morton said more should be done to ensure everyone has the same chance for success after surgery.