The study used the burden of arthritis to examine these connections because 49 million U.S. adults have arthritis, and 21 million suffer activity limitations as a result. The condition is also relatively disabling and painful but not fatal. The researchers found that blue collar workers are much more likely to work past 65 than white collar workers and are much more likely to suffer from conditions like arthritis, reducing their quality of life and work productivity.

The study findings are reported online in the American Journal of Public Health.

The investigators calculated estimates and compared age-and occupational specific data for workers with and without arthritis, merging data from the U.S. National Health Interview Survey (NHIS), Medical Expenditure Panel Survey (MEPS) and National Death Index. They studied 17,967 individuals for the analysis out of 38,473 MEPS participants.

"Arthritis serves as a powerful lens for looking at these convergent phenomena," said Alberto J. Caban-Martinez, DO, PhD, MPH, Department of Epidemiology and Public Health at the University of Miami Miller School of Medicine and first author. "We found that blue-collar workers with arthritis are in much worse health than are all other workers, suggesting that they are struggling to stay in the workforce despite their health condition."

At all ages, blue-collar workers in the workforce are in worse health than white-collar workers. By age 65, 19% of white-collar workers with arthritis remain in the workforce compared with 22% of blue-collar workers. But employed blue-collar workers have more severe disease than employed white-collar workers, and look forward to fewer years of healthy life -- approximately 11 for blue-collar workers and 14 for white-collar workers.

The investigators reported that lower-income workers of older age in the service and farming sectors-- two job types that are unlikely to come with pension plans--are more likely to have arthritis than not, with 58% of service workers and 67% of farm workers continuing to work despite struggling with the painful health condition. Sixteen percent of all blue collar workers are over 65 and 47% report they have arthritis. By contrast, 14% of white collar workers work beyond the age of 65, and 51% of these workers reporting arthritis. Overall, approximately 15% of all workers remain in the workforce at or past retirement age, and 44% have arthritis.

"The increasing age of the U.S. workforce presents new challenges for government, employers and working families," observes Peter Muennig, MD, MPH, associate professor of Health Policy and Management and senior author. "It is estimated that by the year 2030 approximately 67 million adults aged 18 years and older will have arthritis. Because the 'graying' workforce will be disproportionately represented by people from middle and lower occupational classes that also suffer from a higher prevalence of arthritis and a shorter life expectancy than wealthier Americans, Dr. Muennig points out that additional enhancements to federal programs such as better disability, health and unemployment insurance will be needed to maintain a higher quality of life for all workers, particularly for those with chronic conditions such as arthritis. "As the population ages in the face of expanding budget deficits, we face politically difficult choices if the U.S. is to prevent significant declines in its standard of living."

This study was funded by in part the National Institute of Arthritis and Musculoskeletal and Skin Diseases and the National Institute for Occupational Safety and Health.