NASHVILLE, Tenn. (WTVF) — Tennessee is one of 14 states where lawmakers have not approved any kind of plan to expand Medicaid coverage to residents. New research suggests failure to expand that coverage is having detrimental impact on some of the state's most vulnerable residents.

There are currently more than 380,000 people in Tennessee who don't have healthcare coverage. Most either don't qualify for TennCare or can't afford coverage through the Affordable Care Act. Lawmakers in Tennessee turn down about $26 billion a year in federal funding that could help expand TennCare coverage.

New research from Vanderbilt University Medical Center has found that the state's failure to expand Medicaid means residents without coverage aren't as healthy as those in states where Medicaid coverage has been expanded.

For those without insurance, the impacts are devastating.

"To me something needs to be done for those who can't help themselves," says 65-year-old Joanne Sonnenblick.

Sonnenblick is a diabetic who has spent the last five years without health insurance coverage. If the state were to expand Medicaid, she would be covered but as a result, this type 1 diabetic often finds herself skipping doctors appointment or even worse, running out of medication.

"It makes it so you don't want to go to the doctor even though you need to go," she said.

Earlier this month researches at Vanderbilt University Medical Center released a new study which found that in states where Medicaid coverage has been expanded residents, "experienced lower rates of decline in both physical and mental health."

"The evidence is becoming clear that health insurance plays a role in shaping people’s health," said Dr. John Graves who helped publish the findings.

However, its up to lawmakers to to decide the future of Medicaid in Tennessee. NewsChannel 5 has spent the least year reporting on medical debt and the rural healthcare crisis. You can see our series here.