Diabetics who undergo weight-loss surgery can often get off their drugs, according to a new study from Johns Hopkins researchers.

The large national study showed that three-quarters of obese diabetics can ditch the insulin and other sugar-controlling drugs within six months.

That not only frees them of daily shots but can save on medical spending. The study found three years after surgery, average costs dropped more than 70 percent annually.

 “The cost to care for the average obese diabetic person in America is $10,000 a year, which could be cut to $1,800 with a very safe operation that eliminates more than 80 percent of the medications these individuals have depended on,” said Dr. Marty Makary, an associate professor of surgery at the Johns Hopkins University School of Medicine and the study's leader, in a statement. “The results show that bariatric surgery has huge implications for public health and control of health care costs.”

For the study, published in the Archive of Surgery this month, the researchers followed 2,235 adults covered by Blue Cross-Blue Shield insurance who underwent bariatric surgery between 2002 and 2005. Half were taking metformin hydrochloride and 23 percent were on insulin.

They each had bariatric surgery, which makes the stomach smaller with staples. It carries risks – though they are smaller than those associated with diabetes. And it’s costly – about $30,000 – but could save money over the long run, the researchers said.

“Until a successful nonsurgical means for preventing and reversing obesity is developed, bariatric surgery appears to be the only intervention that can result in a sustained reversal of both obesity and type 2 diabetes in most patients receiving it,” Makary said.

Photo of a needle in a bottle of insulin/Los Angeles Times