WARREN — Maine has the eighth highest percentage of prisoners in the country who are 55 years old or older, fueling an increase in state spending for prison health care, according to a national report released Tuesday.

A spokeswoman for the report said states that expand Medicaid coverage are likely to have opportunities for savings, and states that opt not to expand coverage will not.

Maine spent $17 million for prisoner health care in 2011, or $8,027 per inmate. That represents an increase of 16 percent from 2007, according to the report from the Pew Charitable Trust and the John D. and Catherine T. MacArthur Foundation.

Maine was one of 15 states where spending continued to increase throughout the five-year length of the study, according to the report. Most states saw health care spending decline for prisoners toward the end of the study.

Eight percent of people incarcerated in the Maine prison system in 2011 — not including county jails — were older inmates, according to the report. Nationwide, the percentages ranged from a low of 4 percent for Connecticut to a high of 12.4 percent in Oregon.

“Like senior citizens outside prison walls, older inmates are more susceptible to chronic medical and mental conditions, including dementia, impaired mobility, and loss of hearing and vision,” the report stated. “In prison, these ailments necessitate increased staffing levels, more officer training and special housing.”

Older people in prison typically experience the effects of aging sooner than the general population because of substance abuse, inadequate preventative care and inadequate primary care before incarceration, the authors of the report found. Violence and the stress that result from being in prison also contribute to the earlier aging effects, the report concluded.

Recent studies have found the cost of caring for an older, ill inmate is more than three times the average cost for younger, healthier prisoners.

The director of the projects for Pew, Maria Schiff, said during a conference call held Tuesday states that opted to expand their Medicaid programs have opportunities to save state money by enrolling several prisoners.

Efforts to expand Medicaid coverage in Maine have been vetoed by Gov. Paul LePage — vetoes that were upheld by Republicans in the Legislature.

For states that do not expand Medicaid, Schiff said, it will be “business as usual” in terms of paying for prisoners’ health care.

In terms of overall spending, Maine spent the eighth most in the country for health care per prisoner at $8,027. California spent the most at $14,495, while Oklahoma spent only $2,558.

“Health care and corrections have emerged as fiscal pressure points for states in recent years as rapid spending growth in each area has competed for scarce revenue. Not surprisingly, the intersection of these two spheres — health care for prison inmates — also has experienced a ramp-up, reaching nearly $8 billion in 2011,” the report stated.

Officials to the Maine Department of Corrections said they will comment after they review the report, spokesman Scott Fish said Tuesday afternoon.

In 2011, Joseph Ponte, who was commissioner at the time, said he considered enrolling several prisoners on Medicaid, which is partially reimbursed by the federal government.