The study used a research database including nearly 230,000 employees from various industries. The analysis included four years' worth of data, including information on health, disability and workers' compensation costs.

Overall, 15.5 percent of workers were affected by arthritis and associated joint disorders. Workers with these disorders were more likely to be women and tended to be older than other workers. Osteoarthritis and rheumatoid arthritis were the most common diseases, but 70 percent of workers had other joint-related disorders.

Employees with arthritis and related disorders used three times more healthcare services than other workers. With adjustment for other factors, healthcare costs for arthritic workers were higher by about $1,000 per year. Prescription drug costs were nearly $200 higher per year.

Arthritis was also associated with increased costs in other categories. The odds of filing a claim for short-term disability were higher by 150 percent - much higher than for workers with other common conditions, such as asthma or depression. Rates of long-term disability and workers' compensation claims were higher as well. Where information was available, individual productivity was about four percent lower for workers with arthritis, equivalent to about $7,500 in lost productivity.

Including direct healthcare costs and lost productivity, economic losses due to arthritis and related disorders totaled more than $9,000 per person per year.

Arthritis and associated joint disorders are very common in the population and are expected to become even more so as the population ages. The new results confirm the previously reported figure of one in seven people affected. In the future, that proportion is expected to increase to almost one in five.