Rising out-of-pocket costs could shut many middle-income Americans with health coverage out of the U.S. health care system.

Roughly 60% of the U.S. residents who have private health coverage in 2020 may be enrolled in high-deductible plans, according to consultants in the New York office of Booz Allen Hamilton Inc.

Only about 5% of privately insured U.S. residents have health savings accounts or health reimbursement arrangements, but 10% of enrollees in “conventional” plans also have deductibles exceeding $1,000, the consultants report.

Health account plans could cover about 20% to 25% of privately insured U.S. residents by 2020, and conventional plans with high deductibles and high out-of-pocket cost limits could cover 35% to 40% of privately insured U.S. residents, the consultants predict.

In some cases, states that establish universal health insurance programs may find that high deductibles will replace lack of health insurance as the main barrier keeping residents from getting health care, the consultants warn.