Beginning April 1, the 128,000 Medicaid enrollees in the UPMC for You health plan will be charged co-payments ranging from $1 to $3 for hospital stays, doctor visits and X-rays. The payments do not apply to those under 18 years old, nursing facility residents or women who are pregnant or nursing.

The move puts UPMC for You, affiliated with the UPMC Health Plan, in alignment with Highmark and other insurers that already are charging similar co-pays. The maximum amounts are set at the federal level.

Still advocates for the disadvantaged say the co-payments, however small, can loom large for families already struggling with poverty.

"For low-income families -- you're talking about a family of three making $18,000 -- discretionary income is almost nonexistent," said Jennifer Sullivan, senior policy analyst for Families USA.

"So even though it may seem like a small amount, the research in states that have implemented co-payments shows that people drop off the rolls. They don't seek the services, and they delay care until they can't wait any longer, which increases the cost of treating them," she added.

"These things don't save money because they collect a lot of co-payments. They save money because people aren't accessing services."

Dorothy Young, advocate for the Pittsburgh Welfare Rights Organization based at UPMC Mercy, Uptown, said the co-payment could weigh particularly hard on senior citizens. "It could be a real hardship for people to pay that. If you're on a fixed income, it's very hard to get that," she said.

Highmark, the area's largest insurer, provides Medicaid coverage for 255,000 subscribers through the Gateway Health Plan, which has a $2 co-pay for physician visits by adults, except for obstetrical and gynecological exams. The co-payment for inpatient hospital stays is $3 per day. The co-payments "have been in place for several years," said spokeswoman Kristin Ash.

John Lovelace, president of UPMC for You, said the insurer had resisted instituting co-payments until now in part because they cost more money to administer than they brought in. But, without the co-payments, he said UPMC for You has attracted enrollees with more serious illnesses and disabilities.

The plan made $1 million last year, he said, but with $600 million in revenue, the fraction-of-a-percent margin puts them at a risk for future losses.

"We couldn't sustain another year of no co-payment," Mr. Lovelace said. "We're really trying to position ourselves so we don't seem unduly beneficial to people who are sicker. We decided we should look more like our competition. That's basically our rationale."

He said the state Department of Public Welfare pays the health plan about $130 monthly per Medicaid enrollee. If an enrollee requires care that costs more than that, the company absorbs the loss. If the enrollee requires no care, the insurer pockets the $130.

The state's rate did not increase last year, Mr. Lovelace said, while "our costs continue to escalate no matter what DPW decides to pay us."

The co-payment amounts are small. Among them: $3 per day for inpatient hospitalization with a $21 maximum; $2 for outpatient hospital visits; $3 for an emergency room visit; and $1 per visit for X-rays.

Rather than preventing people from getting care, he said, the co-payment "gives people something else to think about" before deciding what course of action to take.

Ms. Sullivan, though, cited studies by groups such as the Kaiser Commission that linked increased co-payments to decreased Medicaid enrollments, and a greater likelihood that people will delay or forgo care.

"There's a lot on their plate -- work expenses, putting food on the table, paying rent. Two or three dollars [for a co-payment] might be the first thing to go."

Medicaid funding and benefits likely will soon play a larger role in the United States as Medicaid eligibility would include an additional 17 million adults under the House and Senate health reform bills.

Coupled with persistent unemployment due to the poor economy, even more families may be edging toward Medicaid eligibility in coming years.

According to the Kaiser Family Foundation, Medicaid enrollment nationwide jumped 3.29 percent in 2009, the biggest jump since the 1960s. As of June 2009, it reported, there were 3.3 million more people enrolled in state Medicaid programs than one year earlier.

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