"Small and rural regions appear to attract fewer entrants. Insurers also charge higher premiums to rural residents," wrote Michael J. Dickstein, an assistant professor of economics at Stanford University, in a brief for the school's Institute for Economic Policy Research.
The study looked at the 33 states that use the federal health-care exchange amd did not include those with state-based exchanges, such as the Pacific Coast states, Colorado, Minnesota, Kentucky, New York and Massachusetts.
Part of the problem is that many states, in creating regions for insurance companies to set rates, segregated rural areas. "Bundling rural counties with larger, urban areas appears to increase the supply of plans available to rural residents," a Stanford news release says.