Health spending as share of GDP drops for first time since 1997 - CNBC.com

Martin said that 2012's rate was not due to "just one prominent trend that affected growth, it was a mixed bag of results."

In particular, a faster rate of growth in 2012 in spending on hospital services, and services from physicians and clinicians was offset by slower rates of growth in the prices of prescription drugs and nursing home services, CMS said. Hospital spending rose 4.9 percent, while physician and clinical services climbed 4.6 percent.

Also up was out-of-pocket spending by consumers, which grew at a 3.8 percent rate in 2012, compared to 3.5 percent in 2011.

Martin said that increase included "increased cost-sharing" for physicians and clinical services, "and the increased enrollment in these high-deductible plans," which have become more prevalent in the private insurance market.

Spending on retail prescription drugs grew slightly, by 0.4 percent in 2012 compared to 2011, as a number of big-selling, high-use drugs including Lipitor, Plavix and Singulair lost patent protection in 2011 and 2012, opening up competition from cheaper generic versions.

Martin noted that so-called patent ciff, which kept down the spending rate of prescription drugs, was "largely a one-time effect."

Another one-time effect came in spending on nursing care facilities and continuing care retirement communities, which saw a 1.6 percent increase in 2012, compared to a 4.3 percent increase seen in 2011. That reduction in 2012 was mainly due to the reduction of Medicare payments to skilled nursing facilities to adjust for a large hike in such payments the prior years.

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While saying the effects of Obamacare on the spending rate were "minimal," the CMS report noted that a provision of the Affordable Care Act began reducing updates of Medicare payments to providers in 2012, which helped keep down the rate of growth in Medicare spending that year.