Student loans sink Mom and Dad

This post comes from AnnaMaria Andriotis at partner site SmartMoney.

A growing number of middle-aged Americans are struggling with student loan debt -- not all of it from their college days.

While borrowers over 40 account for about a third of the nation's $900 billion in student debt, they appear to be struggling with their loan payments more than other age groups, according to a report in The Wall Street Journal. 

For example, the delinquency rate -- the percentage of debt on which a payment has not been made for 90 days -- for Americans aged 40 to 49 was 11.9% in March, compared with 8.7% for borrowers of all ages.

Experts say many of those borrowers over 40 are still paying off balances from their college years. But a growing number of parents are saddled with student loans they took out to pay tuition for their kids. Roughly 17% of parents whose children graduated from college this past spring held federal Parent PLUS loans. That's up from about 10% a decade prior, and less than 6% in 1993, according to FinAid.org. (Post continues below.)

The average balance on these loans: nearly $34,000, up 123% from a decade ago.

Meanwhile, more private lenders are demanding parent co-signers on their student loans. Because most students don't have a credit history, lenders say they turn to their parents' credit to determine whether to approve them, and at what terms. Both the parent's and the student's name appear on the loan, and the lender expects payment from either party.

Missed payments will affect both borrowers' credit scores. And if the student can't pay, the parent is on the hook for the payments.

• Smart Spending on the go: Get our app for Android or iPhone

Since the financial downturn, more than 90% of college loans from private lenders have co-signers, says Mark Kantrowitz, the publisher of FinAid.org, which tracks financial aid and student loans. That's up from roughly 50% prior to 2008.

The ballooning of student loan debt for older Americans highlights a key downside to student loans, say consumer advocates: There's no way out. Unlike all consumer loans, federal and private student loans cannot be wiped out after bankruptcy.

More on SmartMoney and MSN Money:

• 10 things student loan companies won't say
• College: Best investment or big risk?
• More job searches lead to grad school
• Can your student loans be forgiven?
• Over 60 and still paying student loans
• Dad overwhelmed by dead student's loans