Consumer-directed health plans grew 25% last year, reports the American Association of Preferred Provider Organizations, Washington.

The number of Americans enrolled in a CDHP in 2007 grew to 12.5 million, from 10 million in 2006, according to a study conducted for AAPPO by the consulting firm Mercer Inc., New York.

The study found 97% of CDHPs are built on a preferred provider organization network, up 2% from 2006.

The fast growth of the plans is spurring employers to offer more health care information to employees, according to the study report.

Small employers are helping to fuel the growth of CDHPs, with 7% of employers with under 500 employees offering a CDHP in 2007, up from 5% the year before, the study found.