Year-end polls in the last couple of weeks all report that the rising cost of healthcare is among Americans' biggest worries.

Insurance coverage for prescription drugs has been decreasing as their prices have been increasing.

As pbs Wisconsin's Marissa Wojcik learned, not all health plans are created equal.

Marisa Wojcik: Cole schmidtknecht was just 22 years old when he was rushed to the e-r by his roommate.

Unable to breathe.

Bil schmidtknecht: When he arrived at the hospital, he was all lifeless.

He had no pulse.

And they had to resuscitate him.

Marisa Wojcik: By the time his parents bil and Shanon schmidtknecht got to Cole's bedside, doctors had shattering news.

Bil schmidtknecht: What we got told on it was a, you know, just simply that he would never wake up.

Shanon schmidtknecht: They had told us that essentially what we saw laying in the hospital of our son was all that he would ever be.

Marisa Wojcik: Cole had suffered a devastating asthma attack.

For his parents, the cause of death only added to their stunned disbelief.

Shanon schmidtknecht: Cole had had asthma his whole life.

He was on a great medication that stabilized his asthma for the past decade or more.

So we were like, this cannot be.

Marisa Wojcik: As they tried to piece together Cole's final hours, his roommate remembered that Cole did go to the pharmacy days before he died.

Shanon schmidtknecht: His roommate had said, I don't know.

We tried to get it a few days ago and he couldn't afford it.

It was like $500.

Marisa Wojcik: That price shocked Cole's parents since his copay had always been less than 70 dollars.

But what they didn't realize was that a recent shift in how his company provided health coverage would cause, without any notice, the out-of-pocket price of the inhaler he needed to skyrocket 800% - well beyond his budget.

What was the shift?his employer had moved from traditional health insurance to a form of coverage known as a self-funded health plan.

Millions of Americans get their coverage this way.

But health advocates say patient confusion and ignorance about the subtle differences between these two types of coverage can have devastating impacts for patients like cole.shanon schmidtknecht: I will never forget that leaving that pharmacy and being like, my god, that this is what happened to Cole.

>> It gets old after a while.

Marisa Wojcik: Kevin Voltz ran into similar problems with his self-funded health plan.

In his case, he was battling chronic lymphocytic leukemia - a type of blood cancer.

Kevin Voltz: All of a sudden my numbers were at like 167,000 compared to like 4 or 5000.

Marisa Wojcik: He was in urgent need of treatment.

His oncologist had a prescription that was promising• but would come at a price.

Kevin Voltz: She said, we need.

We need $13,000 before we can ship this.

And I said, $13,000.

Yes, that's what this drug costs to be delivered withoutinsurance.

Marisa Wojcik: 13-thousand dollars• per month.

Kevin's self-funded health plan wouldn't cover a dime of the medication, calling it a non-preferred specialty drug - which meant he was on the hook for 100 percent of the cost - nearly 100 thousand dollars.

Kevin Voltz: Nobody could do that.

I don't care who you are.

Marisa Wojcik: His medical care team sent appeal after appeal pleading with his health plan to cover some portion of his medicine.

Kevin Voltz: They got lots of denial letters and stuff over the months saying that there was nothing they could do.

And I'm running low on my month's supply.

And what am I going to do next month?

Marisa Wojcik: Traditional, fully insured health plans are supposed to ease those kinds of fears.

They must follow all federal and state laws.

Including notifying patients of changes to their prescription coverage, and limiting how much a patient can be forced to shoulder out of pocket.

By contrast, self-funded plans like Cole schmidtknecht's and Kevin Voltz's, are regulated only under federal law - not state insurance laws, which are usually more stringent.

Sarah Davis: A self-funded plan is not insurance.

>> Sarah Davis is the cor of -- a research and advocacy program at the university of Wisconsin Madison.

She says it's often difficult for people to even know what kind of plan they have.

It takes advocates and patients sometimes quite a bit of time to parse out and figure out that it is not insurance.

If there are claims being denied, the protections that that consumer has are reduced in self-funded plans.

Marisa Wojcik: In recent years, these self funded plans have become the most predominant form of employer-provided health coverage in the United States.

Some 63% of plans are self-funded.

Why the growth?

As health care costs rise, these plans save employers money by offering greater cost control and flexibility compared to traditional insurance.

Mike Roche: Self-funding lets the employer take control of the second or third biggest line item on their budget.

The last few years, that's been a double-digit increase.

>> Mike Roche is director of development at the alliance and helps design self--funded plans for companies across T midwest.

What employees need to know is that your employer has now become the insurance company.

Marisa Wojcik: After exhausting nearly every possible avenue to pay for his cancer medicine, Kevin Voltz received good news from his clinic's drug insurance specialist.

Kevin Voltz: She kept calling me and calling me and calling me.

And she couldn't tell me the news fast enough that they had come through.

Marisa Wojcik: The drug manufacturer informed the clinic they would provide the remaining dosage of his treatment, at no cost, but did not provide an explanation.

>> Don't let another parent stand where we are today.

One year after their son's passing, bil and Shanon schmidtknecht are still searching answers, and advocating for change.

Shanon schmidtknecht: The fact that someone has to pass away because he can't afford his medication in the United States of America is unacceptable.

Bil schmidtknecht: No matter what happens, it was totally preventable.

I mean, like it was preventable.

Shanon schmidtknecht: This can not happen.

This cannot happen to another family.

Marisa Wojcik: For pbs news weekend, I'm Marisa Wojcik in Madison, Wisconsin.