The recent U.S. economic recession was the longest and most severe since World War II. During this period, personal spending on health care grew at the slowest rate in over 50 years, suggesting that Americans used less health care.

A new study finds that these cut backs were not limited to Americans who lost their health insurance, nor restricted to unnecessary services. Researchers at the University of North Carolina at Chapel Hill School of Medicine found that during the recession, continuously insured Americans underwent fewer screening colonoscopies, a cost-effective, recommended preventive service. The study appears in the March issue of the journal Clinical Gastroenterology and Hepatology.

The investigators estimated that during the recession period, dating from December 2007 to June 2009, roughly one- half million fewer Americans covered by commercial health insurance underwent colonoscopy screening for colorectal cancer than expected based on use in the preceding two years.

These time periods were defined by the National Bureau of Economic Research, the nation's leading nonprofit economic research organization and the official arbiter for dating recessions.

The study of 50 to 64 year olds also found a strong link between direct out-of-pocket (OOP) costs for this elective procedure and whether or not patients were more likely to get screened as their doctors recommended.

"We found that patients facing high out-of-pocket costs were less likely to undergo colonoscopy at any time point, especially during the recession," noted Spencer D. Dorn, MD, MPH, assistant professor of medicine in the division of gastroenterology and hepatology at UNC. "Before the recession, these individuals were less likely to get a screening colonoscopy, but the gap in use between those with high and low out-of-pocket costs was narrowing. But when the recession hit full force, the discrepancy in use widened again." Low OOP was defined $50 or less; high OOP, $300 or more.

The researchers led by Dorn analyzed data from 106 U.S. health plans that fed into the IMS LifeLink Health Plan Claims Database. Dorn points out that this is nationally representative of the commercially insured U.S. population, and does not include those served by Medicare or Medicaid.

"These findings reflect the intimate link between socioeconomic factors and health care use," the authors state. When faced with the stress of economic insecurity, otherwise healthy people who are covered by health insurance "may be unable to afford screening colonoscopy, or may perceive it to be less important than competing demands for limited resources."

The findings, say the authors add to the growing evidence that cost sharing is a disincentive for preventive health services. For example, requiring women to pay a $10 to $20 co-pay, has been shown to make them less likely to undergo screening mammography.

"Taken together, these studies argue for strategies to reduce patient cost sharing for colorectal cancer screening," the report states.

The new health care reform act has eliminated Medicare and Medicaid copayments and deductible requirements for all federally recommended preventive services, including colorectal cancer screening. The authors suggest that commercial insurers "follow suit" by exploring new ways to reduce patient cost-sharing.