Cancer among American workers costs the businesses where they work billions of dollars a year in lost productivity, new research finds.

A study led by Grant Skrepnek of the University of Arizona Cancer Center in Tucson revealed that cancer in U.S. employees results in more than 33 million disability days per year, which amounts to $7.5 billion in lost productivity. Based on data from 2004 to 2008, the researchers estimate that 3.3 million American workers are diagnosed with cancer annually.

The study shows smaller businesses are most affected. Of the workers with cancer that were analyzed, nearly 85 percent worked for companies with fewer than 500 employees. In addition, these small-business employees who had cancer were also more likely to be uninsured and had higher rates of other health problems, such as high blood pressure, depression and chronic obstructive pulmonary disease.

The research, one of the first to document the economic impact of cancer on the U.S. workforce, revealed that certain types of cancers, including women's cancers and melanoma, were associated with higher burdens of illness. For breast cancer, health care costs and hospitalizations were twice as high and disability days 55 percent higher than for other cancers.

The study's authors believe the true cost in terms of lost productivity is likely even higher than the disability days measured. Based on the results, they call for further efforts to reduce the burden of illness associated with cancer and its treatment.

The research was published in this month's edition of theJournal of Occupational and Environmental Medicine, the official publication of the American College of Occupational and Environmental Medicine.

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