Perhaps putting added pressure on insurers as they prepare to set rates for 2015, new evidence suggests that people enrolled in health plans under the Affordable Care Act have higher rates of serious health conditions than those with other coverage. As The Wall Street Journal reported, this analysis comes from health-technology firm Inovalon Inc, which examined medical claims of those enrolled in the health law’s exchanges in the first quarter of this year.

According to Inovalon’s data, among those health care exchange enrollees  who have seen a doctor or health care-provider during the first quarter, about 27% have serious medical conditions, including diabetes, heart issues, cancer, or psychiatric conditions. Among those who held on to their existing individual plans, the rate was much lower, with 12% experiencing significant health issues. The rate was also higher than the 16% figure for last year’s individual- consumer market over the same time frame.

These findings paint a picture of a sharply bifurcated consumer insurance market, with healthier people remaining with their previous coverage and sicker and costlier people enrolled through the health reform law. As the WSJ article points out, insurers have warned that this dynamic could potentially drive up premiums. “We’re seeing more chronic conditions than what we would have expected,” Patrick Getzen, chief actuary for Blue Cross & Blue Shield of North Carolina, said of the new health law enrollees, telling the WSJ that this development will “put pressure on the 2015 rates.”

Still, as the WSJ points out, Inovalon’s data does not include people who signed up for the exchange plans in the final weeks of the enrollment period, which was extended into April. Insurers have indicated that during those final weeks, they received younger and perhaps healthier enrollees. A spokesman for the Centers for Medicare and Medicaid Services also told the WSJthat the health law includes protections for insurers that enroll sicker people, and that more insurers are participating in the exchange next year, which should create “increased competition and provid(e) consumers with even more affordable coverage.”

Over 8 million people enrolled in the health law’s exchanges by mid-April, according to data reported by the Obama Administration. The second enrollment season is set to begin November 15.