U.S. hospital admissions for child abuse have risen in the past decade, and the increase may be related to the housing crisis of recent years, a study suggests.
Researchers found that between 2000 and 2009, admissions for physical abuse at U.S. pediatric hospitals peaked in 2008 - right about the time housing foreclosures were taking off in many parts of the country.
In general, as a local area's rate of delinquent mortgages and housing foreclosures rose, so did its rate of child abuse admissions, according to the findings reported in the journal Pediatrics. 
That doesn't prove the housing crisis is to blame. "This type of study can't demonstrate causation. It can only show an association," said lead researcher Dr Joanne Wood of Children's Hospital of Philadelphia.
She said it is possible that housing foreclosures signal the "serious end result" of families' economic hard times - when, for example, they've been out of work for a long time and their savings and "safety net" benefits have run out.
That could put more children at risk.
LESS SEVERE CHILD ABUSE DOWN
The findings are based on a database that tracks discharges from pediatric hospitals in major metropolitan areas.
Between 2000 and 2009, there were just over 11,800 admissions for physical abuse of children younger than six at 38 hospitals. That accounted for 0.28 percent of the nearly 4.2 million admissions in those hospitals overall.
Over the years that rate fluctuated, peaking at 0.3 percent in 2008.
The researchers then looked at each metropolitan area's unemployment rates and housing woes. They found that for each percentage increase in an area's foreclosure rate, admissions for physical abuse rose 6.5 percent the following year. There was a similar pattern when Wood's team looked at 90-day mortgage delinquency rates.
There was no link between unemployment and child abuse admissions. Wood speculated that unemployment is a less extreme marker of a family's economic problems than mortgage delinquencies and foreclosures.
The results appear to contradict some past research that has suggested child abuse is declining in the U.S., Wood and her colleagues say.
The reason may be the data source, Wood said. Those past studies have looked at reports to child protective services, which cover varying degrees of abuse. Children admitted to the hospital would be victims of only the most severe physical abuse.
There is "reasonable evidence" that other forms of child maltreatment are declining, said Dr Kristine Campbell, a pediatrician at the University of Utah in Salt Lake City, who has studied the issue.
"There are still huge problems in terms of kids who are being severely abused," said Campbell, who was not involved in the new study.
Like Wood, she said it is impossible to go beyond observing the correlation between foreclosures and mistreatment. "We don't know that economic stress causes child abuse," Campbell said.
There could be complex reasons for the relationship, according to Campbell. It's possible, for example, that when a family loses their home, they may end up living with someone else who is not used to having children around, and that's when the abuse occurs.
In any case, Campbell said, "This study adds to a large body of evidence that economic downturns are bad for families and bad for children."
That includes negative effects on kids' nutrition, school work and general health.
"Economic downturns are exactly the time when we should not be cutting services to families," Campbell said. She pointed to government programs like WIC, the supplemental program for women, infants, and children that offers nutrition assistance to low-income women who are pregnant or have young children.