I'm going to change company names here to keep DU out of hot water, but the blanks are easy enough to fill in.
I have health insurance with a company we'll call "Insurer." I described some symptoms to my GP, who is part of a State University Medical Network. Normally, the State University Medical Network prefers an in-house sleep study, followed by prescribing any necessary equipment and then the patient picks a local provider -- usually someone with an RT (respiratory therapist) that helps with mask selection, sizing, etc. But Insurer uses a 3rd Party Administrator for all of the aspects of their Sleep Disorder patients. We'll call them "TPA." TPA immediately says "No!" to the in-house study, and instead has me do a home study. I do that. State University Medical Network reads the study, and says I have "Severe Obstructive Sleep Apnea." TPA works their deal like this: I can't select a provider or a durable medical equipment dealer. They have a deal with a well-known National DME Provider (DME = durable medical equipment) that I'm forced to use. TPA bills me monthly for the CPAP on a rent-to-own deal, and I have to agree to be spied on - to have the device wirelessly report that I'm using it for 4+ hours per night or Insurer won't cover. National DME Provider ships the CPAP right away - but no fittings; no choice of masks; no lesson from an RT. I'm directed to links to online instructional videos. As part of being spied on, there is a phone app that reports on how you are doing. It kept saying I was having too many incidents during the night, and it was underreporting my use time. I had to call a lot of people to finally get to the local branch of National DME Provider and meat with a live RT. To be fair, she was helpful and got me a new mask that solved the problem. However, when it came time to order new masks (more on that presently), they wanted to send the old-style mask, not the one I'd been switched to.
So once you get the ResMed, you then see the full extent of how this scam works. For those that don't own a CPAP, there is the machine (lasts 5 years +/-), but there are also a lot of parts - a humidifier tank that holds water that humidifies the air you breathe; the tubing (which has a heating element); the mask; the stretchy cloth thing that holds the mask to your head. Everything that is not the machine gets replaced. National DME Provider makes its money by arranging frequent replacement intervals with Insurer and rates negotiated by TPA. So I get a call saying I am eligible to order new masks, new hose, new filters, etc. If I say "yes" (and why wouldn't I - it's getting billed to Insurer, right?) National DME Provider sends me the stuff. But then TPA bills me - generally for about 20% of what National DME Provider charges Insurer - and they robocall religiously. And they also send emails trying to sell me a SoClean (boy do they want to sell me a SoClean - ~350, in case you were wondering). I've come to find out some of this stuff is available on Amazon for about what my co-pays are. I also own the unit now, so if I want to go to a local DME shop, I am free to do so. The rub is I won't get reimbursed by insurance, but if I get to see an RT, get better advice on what masks to buy, etc. it's worth it to me.
Sanders talks about the Pharma companies and the For-profit insurers being the guilty parties for high health care costs. I have to disagree - it's the whole damn lot of them. The doctors, the drug stores (they just did a story here on CVS billing Medicare 10x what a local pharmacy was billing for the same drug), the hospitals, the DME providers, and the administrators (who are supposed to be controlling costs) all have their hands in our pockets.
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But I suppose we're all taxpayers anyway. 
