(Reuters Health) - Millions of Americans suffering from serious illness lack access to care that could improve their quality of life by relieving pain and other symptoms, a study finds.

Access to so-called palliative care is greatest in the New England, Pacific and mid-Atlantic regions of the U.S., researchers report in the Journal of Palliative Medicine. Far fewer hospitals have palliative care programs in the Southern states.

People who live near larger hospitals are also more likely to have access to palliative care – it's offered in 90 percent of hospitals with at least 300 beds but just 56 percent of hospitals with fewer beds.

While variation in access to palliative care isn’t surprising and mirrors what happens in many areas of medicine, the study findings help identify gaps in care that could be improved, said senior author Dr. Sean Morrison, a researcher in geriatrics and palliative medicine at Icahn School of Medicine at Mount Sinai in New York.

"Considerable data now demonstrates that when patients receive palliative care in addition to traditional medical care, they have improved quality of life, greater satisfaction with their medical care, are less likely to be re-admitted to the hospital or have to visit an emergency department, and in certain diseases (i.e. cancer) have greater survival," Morrison said by email.

Morrison and colleagues analyzed data from a variety of sources including the U.S. census and the American Hospital Association as well as from interviews with hospital administrators and program directors.

In addition to hospital size, they found institutions' tax status was also a significant predictor of access to palliative care.

Not-for-profit and public hospitals were, respectively, 4.8 times and 7.1 times more likely to have a palliative care program than for-profit hospitals, the study found.

Regional variation in palliative care was also pretty stark. In New England, 88 percent of hospitals had palliative care programs, as did 77 percent of hospitals in the Pacific and mid-Atlantic states. In the south-central regions, slightly more than 40 percent of hospitals had programs.

Overall, access is much better now than it was less than a decade ago, however.

At the end of 2014, 67 percent of hospitals with 50 beds or more had palliative care programs, up from 53 percent in a report published in 2008 and just 15 percent in a 2001 report.

One limitation of the study is that it only assessed whether or not hospitals had palliative care programs, and lacked detailed information on how these programs were structured or staffed, how many patients they treated or the quality of care provided, the authors acknowledge.

It's possible, also, that regional variation in palliative care reflects a larger problem with health disparities, said Joy Goldsmith, a palliative care and hospice researcher at the University of Memphis in Tennessee who wasn't involved in the study.

"Palliative care that is systematically engaged indicates resources that have been invested in this innovation," Goldsmith said by email. "The regions representing the least expansive growth in palliative care are regions that struggle the most in health disparities, obesity and comorbidities."

SOURCE: http://bit.ly/1LUkpQk Journal of Palliative Medicine, online September 29, 2015.