Children diagnosed with type 2 diabetes face a high likelihood of developing complications before age 30, a new study suggests.

Researchers found that among 500 children and teenagers with type 2 diabetes, 60% developed at least one complication over the next 15 years — including nerve damage, eye disease and kidney disease.

Type 2 diabetes, which is often associated with older age and obesity, was once seen almost exclusively in adults. But as childhood obesity has climbed in recent decades, more kids are being diagnosed with the condition.

Type 2 diabetes arises when the body can no longer properly use the hormone insulin, which regulates blood sugar levels. As a result, those sugar levels can soar, and that can damage blood vessels and various organs over time.

The new findings -- published July 29 in the New England Journal of Medicine -- show just how rapidly complications can arise.

By the end of the study period, participants were 26 years old, on average. Yet 55% had kidney disease, one-third had nerve damage, and half had eye disease related to blood vessel damage.

"To some extent, this confirms what we'd suspected, but didn't know," said Dr. Philip Zeitler, one of the researchers on the study.

"There remains a question of whether kids develop complications any faster than adults do. But it doesn't happen more slowly," said Zeitler, a pediatric endocrinologist at Children's Hospital Colorado, in Aurora.

Even in children, he said, "the disease is potentially very aggressive. It needs to be taken seriously."

There is no simple solution, however. Oral medication, like metformin, as well as insulin can be used to control elevated blood sugar.

But even in young people, diabetes commonly goes hand-in-hand with elevated blood pressure and unhealthy levels of LDL ("bad") cholesterol, which are themselves risk factors for the complications seen in this study.

At the outset, when study participants were 14 years old, on average, about 20% had unhealthy blood pressure or cholesterol levels. By their late 20s, 67% had high blood pressure and just over half had high cholesterol.

A healthy diet, regular exercise and weight loss, if needed, are central to managing all those problems. But, Zeitler said, that's easier said than done for families who can't afford healthy foods, or have no safe place for their kids to exercise.

"This is really a social problem," he said. "It's a reflection of the breakdown in our social safety net."

Among his team's findings: Black kids and Hispanic kids were 80% and 57% more likely, respectively, to develop complications than white kids were.

Dr. Molly Regelmann is a pediatric endocrinologist at Children's Hospital at Montefiore in New York City.

She said that kids with type 2 diabetes fare best when families are able to make changes to the whole household's diet and exercise habits. And that can be a challenge.

"Rates of obesity and type 2 diabetes tend to be higher in 'food deserts' — areas with limited access to fresh and healthful foods in grocery stores and farm stands," said Regelmann, who was not involved in the study.

Those same areas may lack safe places for exercise, too. And the pandemic likely compounded that problem, she added.

"School closures during the COVID-19 pandemic have led to fewer opportunities for organized sports and physical education classes," Regelmann said. "The pandemic has also caused gym closures, and in areas where public transportation is necessary to reach open spaces, families have had to weigh risks and benefits of exercise with potential exposures to infection."

As for medication, Zeitler said, there is often hesitancy to use it to manage kids' blood pressure and cholesterol.

But at his center, he said, they are "more aggressive" in prescribing those medications to kids with type 2 diabetes.

Regelmann agreed that the "threshold" for starting medication is lower for kids who have diabetes than for those without.

There also are fewer options for controlling kids' blood sugar, compared with adults. At the time of the study, Zeitler said, the only approved treatments for patients under 18 were metformin and insulin.

Some newer medications approved for adults, Regelmann said, have been shown to not only lower blood sugar, but also curb the risk of complications.

"This study highlights the need to test these medications in younger patients," she said.