Tens of thousands of Minnesotans gained health coverage between 2013 and 2015, pushing the state's uninsured rate to an all-time low as federal health reform took hold across the state.

A biannual survey released Monday by the Minnesota Department of Health and the University of Minnesota showed that 213,000 more residents had health insurance last year compared to 2013. The share of Minnesotans lacking coverage plummeted from 8.2 percent to 4.3 percent, with progress in virtually all demographic groups.

State officials hailed the role of MNsure, despite vexing technical problems for the online marketplace, for connecting more Minnesotans with coverage they previously lacked or couldn't afford. Expanded eligibility for the state's Medicaid program helped as well, along with new rules allowing young adults to remain on their parents' health plans.

The results were "an unprecedented advance for the health and security of Minnesota families — particularly those who had previously been lost in the gaps of our system," said Dr. Ed Ehlinger, state health commissioner.

Given the millions of dollars invested in MNsure, anything less might have been seen as a disappointment. State health officials acknowledged that their own internal goal for 2015 was an uninsured rate below 5 percent.

Still, they cited several promising trends in the survey, which queried 11,178 Minnesotans last fall about their insurance status. Most encouraging was progress in the subgroups that historically have been tough to insure, said Stefan Gildemeister, state health economist.

People who lack health insurance for an entire year have caused more concern than Minnesotans who experience a temporary loss of coverage due to job changes or other life events, for example. And that rate of "long-term uninsured" dipped from 6.1 percent in 2013 to 2.2 percent last year.

"This is particularly important and great news," Gildemeister said, "because as individuals are without insurance for a longer period of time, their chance of requiring medical care with potentially substantial financial implications really increases."

Ken Avidor, 60, and his wife couldn't afford health coverage from their freelance artist business — which among other things provides courtroom sketches to the media — until they gained subsidies through MNsure.

Coverage allowed Avidor to receive his first colonoscopy, he said. "It was a good thing they did it, because they found a polyp and snipped it out."

Another sharp improvement came for adults ages 55 to 64, who have had higher uninsured rates in the past. Some have bided their time until qualifying for Medicare at age 65, while others had medical conditions that excluded them from plans for sale on the individual market.

But the federal Affordable Care Act of 2010 prevents health plans on the exchanges from excluding anyone based on prior medical conditions, and the state survey saw a sharp drop in the uninsured rate for this population.

Coverage by public programs such as Medicaid and MinnesotaCare accounted for about half the overall gains — they covered 33.6 percent of Minnesotans in 2015, up from 31.1 in 2013 — with the rest coming from private insurance.

Many still not insured

The results weren't all cause for celebration. Approximately 234,000 Minnesotans still lack coverage — most of them people who are eligible for public programs or tax credits but haven't applied. And while the uninsured rate among Hispanic Minnesotans dropped from 34.7 percent in 2013 to 11.7 percent last year, that's still far higher than the rate for non-Hispanic white Minnesotans.

Dania Aguirre, a 19-year-old nursing student and part-time cafeteria worker, is excluded from MNsure premium subsidies because of her immigration status. Her family came to the U.S. when she was 3, so while she lives in the country legally, Aguirre is in a special category of young Hispanic immigrants who are ineligible for subsidies.

Discounted medication for an enlarged thyroid gland has run out, so she isn't taking it until she can afford to see a specialist. The drug shrank her gumball-sized pituitary gland, relieving the pressure on her eyes that caused blurred vision.

"I'm starting to get it again," she said of her vision problem.

Other Minnesotans are eligible for a subsidy but are leaving "money on the table" by not applying for it, said MNsure chief executive Allison O'Toole. The exchange will continue to reach out to these people and to nonprofit agencies to help them enroll.

Whether state officials should try driving the uninsured rate to zero is an open question. Insurers could offer bargain plans with low premiums but few benefits, which would reduce the uninsured rate but wouldn't really help people afford care, Gildemeister said.

"Getting people into coverage at all costs at all points in time may not be the most important point," he said.

Whether the current crop of plans already forces consumers to take weak benefits for low premiums is unclear. Additional analysis of the survey data in the coming weeks will address whether people are using and gaining value from the benefits they have purchased.

Avidor and his wife chose a plan with low premiums but a high deductible that would sap their savings if either of them suffered a severe illness. It's a bit of a gamble, Avidor said, but they walk and bike everywhere and eat right to stay healthy and avoid illness.

"This is what we've got," Avidor said of his health plan, "and it's pretty darn good."