Health insurance premiums have been skyrocketing a little more slowly lately, and that may have eased pressure on workers’ efforts to prepare for retirement.

The medical costs underlying U.S. health coverage rates appear to be set to go up about 12% for conventional preferred provider organization plans in 2007 and about 11% for plans that incorporate personal health accounts, according to researchers in the Washington office of PricewaterhouseCoopers L.L.P.

But employers used changes in plan design and other techniques to hold the actual increase in 2006 health insurance rates to 7.7%.

The 2006 increase was down from 9.2% in 2005, and it’s the smallest increase since 2000 the PricewaterhouseCoopers researchers have recorded.

“The 7.7% average increase in health insurance premiums in 2006 was twice the rate of overall inflation and wage gains,” the researchers warn.

But even that partial respite, combined with a strengthening of the job market and retirement education programs, may have put workers in a slightly more optimistic mood about their ability both to pay for health care today and to save for retirement.

Researchers at Ameriprise Financial Inc., Minneapolis, have published statistics on the mood shift in a summary of a 2005 survey of 706 U.S. workers who get health coverage from their employers and participate in their employers’ 401(k) plans.

About 61% of the participants said they might reduce discretionary spending to offset the cost increase in their health care coverage, up from 59% in 2004.

But only 22% of the participants said they might cut back on spending on employer-sponsored benefits, such as 401(k) plans and group life insurance, down from 27% in 2004, the Ameriprise researchers report.

Similarly, although 29% of the participants said a significant increase in their health care costs would cause them to consider reducing 401(k) plan contributions, that share was down from 34% in 2004.