This news is discouraging, but hardly unexpected. According to a Marketplace report, a survey by the Transamerica Center for Retirement Studies (pdf here) finds that the share of workers borrowing from their 401(k) retirement funds increased from 11% in 2006 to 18% in 2007. Nearly half of those taking out such loans in 2007 cited the need to pay off debt, compared to a quarter in 2006.

Stagnant wages and salaries, most spouses already employed, rising health care and college tuition costs, higher mortgage debt loads, and falling home values mean lots of American households — including many middle-income ones — are pinched financially. The late 1990s economic boom lessened the strain for a while. Then home equity loans helped. More recently, credit card usage has jumped. Borrowing against retirement savings is the logical next step.

See more discussion here, here, and here.