By Elise Viebeck - 08/27/13 08:02 PM EDT
Many in this population will have higher incomes than their younger counterparts, reducing the subsidies for which they are eligible in the new marketplaces.
This factor, combined with the already higher cost of healthcare for older patients, could result in fewer people from that group entering the new exchanges, researchers said.
"People who are not yet eligible for Medicare and hover near 400 percent of poverty are going to approach the individual market with trepidation," the study stated.
"While the public policy arguments are heavily focused on keeping prices low enough to attract younger, healthier applicants, the effect of the solutions will be to introduce a so-called 'rate shock' to many consumers in their late 50s and early 60s."
The uninsured will soon face a choice as ObamaCare's insurance marketplaces open for enrollment on Oct. 1.
Penalties for not carrying coverage will start in 2014 at $95 or 1 percent of household income. These fines will increase substantially to $695 per person or 2.5 percent of household income by 2016.
Tuesday's study was conducted in partnership with HealthPocket, a consumer resource on health insurance.