"Right now, we have substantial protections," said Wrobel, the Geisinger chief actuary. But in 2017, "It's a completely different game, because we have only one of the 3Rs," he said.
"Our big concern ... is that our membership has consistent premium increases from year to year," Wrobel said. "That's going to be where the real challenge is."
But if premiums are increased more dramatically, as a number of insurers have proposed for 2016, there's a risk that some healthy customers will opt not to enroll in those plans.That would leave them with costlier, less healthy customers.
"If you look at some of the premium increases, there is a potential for deterioration of the risk pool," he said.
Wrobel raised another concern, about the timing of risk adjustment payments to insurers, which he recently wrote about in the Morning Consult.
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The payments to and from insurers under the risk adjustment program for the 2014 plan year are due to be announced June 30—well after most insurers had to calculate their proposed premiums for 2016.
"We're flying blind," Wrobel said. "We still don't have clarity on 2014 and our true performance."
In his article, Wrobel wrote, "Depending on the circumstance for each plan, the risk adjustment information released on June 30 could be critical in developing accurate rates for 2016."
He also wrote that the information about payments released that day could affect how regulators review the proposed rates, "and result in significant changes to the originally submitted rates."
Wrobel said the disparity in timing between when insurers are supposed to file proposed rates for the coming year, and when the risk adjustment payments for the prior year are released, will continue unless CMS does something about it.
He noted that insurers will, in the first half of 2016, have to propose rates for 2017 knowing the reinsurance and risk corridor programs won't be in effect, and with data on risk adjustment payments only as recent as 2014.
"The risk pool could change substantially between these contract years," he wrote. As a result,"many health plans will be facing very substantial pricing risk, which will be especially challenging for smaller plans," Wrobel wrote.