The cost of health benefits for large employers in the Baltimore-Washington area grew 12.6 percent this year, outpacing the national average of 11.5 percent, according to a survey released today by Mercer Human Resource Consulting, a company that advises businesses on benefits.

The news was even worse for small employers, those with fewer than 500 workers. Nationwide, premiums jumped 18.1 percent. The survey does not break out a Baltimore-Washington figure for small companies.

Further, the survey shows, while employers are paying the same share of the weekly premium, they have shifted more costs to their workers through increases in co-payments and deductibles.

"The first thing employers have done is look at where they can cost-shift," said Tracy Cassidy Watts, a senior consultant in Mercer's Washington-Baltimore office.

For example, she said, the survey nationally shows that the average deductible (the amount a patient must pay before insurance coverage kicks in) for out-of-network care in a preferred-provider organization grew to $350 this year from $300 the previous year.

Co-payments (the patient's share of the cost) for brand-name drugs, the survey shows, increased to an average of $35 per prescription this year, from $31 last year.

Watts, who works mostly with clients with 2,000 or more employees, said companies with which she worked have found even more ways to shift costs for the coming year.

Typically, she said, companies were getting bids for premium increases of around 18 percent. By shifting costs through increasing out-of-pocket charges, she said, they have been able to get premium increases down to 12 percent or 14 percent.

In addition to increasing some existing charges, Watts said, some employers have imposed out-of-pocket charges that hadn't existed before, such as for inpatient hospital stays.

In some cases, Watts said, the added out-of-pocket charges are designed to make people think carefully before using health services.

Raymond Brusca, vice president of benefits for Black & Decker Corp., said the power-tool maker had just raised the co-payment on emergency room visits from $50 to $75, after finding "a good half of the visits were for people using the emergency room for routine care."

Towson-based Black & Decker provides health coverage for 27,000 employees, retirees and dependents.

Watts said small employers' rates are going up more because it's harder for them to shift costs. They are not big enough to get customized benefits packages from insurers and, also, small employers offer fewer benefits, so they can't cut back much more.

While cost-shifting has helped reduce employers' premium increases, Watts said, other trends are working to drive up prices - inflation in the price of health care and an aging work force.

While general inflation last year was only about 2 percent, Watts said, medical inflation (reflecting higher use and new treatments as well as higher prices) was about 15 percent.

Brusca said that a soft economy has encouraged workers to postpone retirement. Over the past two years at Black & Decker, he said, the average age of the work force has jumped from 39 to 43.

While there are a number of surveys on health costs, Mercer's is the only one that measures actual growth of Baltimore-Washington employer health costs for the past year.

A survey of health insurers released last month by another benefits consultant, Aon Consulting, predicted premium increases in Maryland for next year of 15.1 percent for HMOs and 15.8 percent for preferred-provider plans, which use a network of doctors but do not require patients to use a "gate-keeper" physician to access services.

The Aon Consulting numbers are close to those in the Mercer's survey, in which employers projected a premium increase of about 14 percent for the coming year.