A managed care giant says it has evidence that health reimbursement arrangements change the way individuals use health care.

Researchers at the company, UnitedHealth Group Inc., Minnetonka, Minn., looked at data for 2003, 2004 and 2005 for 40,000 individuals enrolled in high-deductible health insurance plans linked to HRAs and 15,000 individuals enrolled in traditional preferred provider organization plans.

The HRA holders and the PPO plan members worked for the same employers.

The HRA holders were somewhat more likely to seek preventive care than PPO plan members, but the HRA holders were 14% less likely to visit the emergency room and 22% less likely to be admitted to the hospital, according to UnitedHealth.

Chronically ill HRA holders were about as likely to visit their primary care doctors as chronically ill PPO plan members were, but they were 12% less likely to visit the emergency room and 8% less likely to be admitted to the hospital, UnitedHealth says.

Care costs per member fell about 3% to 5% for the HRA holders while rising about 8% to 10% for the PPO plan members, UnitedHealth says.

UnitedHealth says it tried to adjust for factors such as demographics, health status, plan design impact and geography when comparing HRA holder and PPO plan member cost statistics.

UnitedHealth researchers also looked at data for 130,000 plan members who have high-deductible health insurance from UnitedHealth units and have opened HSAs at UnitedHealth’s HSA bank.

HSA holders who opened accounts in early 2005 now have an average balance of $1,112, and about 60% of employers with HSA plans help fund the HSAs, UnitedHealth says.

At employers that help fund the HSAs, about 90% of the eligible employees open HSAs, UnitedHealth says.