Study on arthritis-attributable work limitation

Mar 29 2007

Arthritis, a leading cause of disability among US adults, affects 46 million people. Arthritis-attributable work limitation (AAWL) can have substantial social and economic impacts including absenteeism, reduced productivity, work loss and lower income.

Some studies have examined work limitations for people with specific rheumatic conditions, but none have presented a complete picture for the entire spectrum of arthritis in the general population. A new study published in the April 2007 issue of Arthritis Care & Research estimated the prevalence of AAWL in adults between the ages of 18 and 64 and examined characteristics related to AAWL in this age group.

Led by Kristina A. Theis, MPH, of the Centers for Disease Control and Prevention in Atlanta, Georgia, researchers analyzed data from the 2002 National Health Interview Survey, which was administered to more than 31,000 adults over the age of 18. The survey included questions about whether respondents had been diagnosed with arthritis by a doctor and whether arthritis or joint symptoms affected whether they worked, and the type or the amount of work they did. Based on their answers, an estimated 6.9 million individuals have AAWL. Respondents were also asked about their physical activity, the presence of chronic co-conditions, limitations not related to work, the severity of their joint pain, their work status and disability payments, and their health access and utilization.

The results showed that among working age adults, 1 in 20 reported AAWL, and, among those with arthritis, 1 in 3 reported AAWL. Adults with arthritis and AAWL had multiple indicators of poor physical health and function, such as high body mass index, joint pain, physical limitations in several activities, and frequent doctor's office visits. AAWL was more common in older age groups and, when adjusted for age, was found to have a higher prevalence among women, non-Hispanic blacks, and individuals with lower education and income.

The authors point out that the findings of the study are subject to limitations typical of observational studies. The information was collected by self-report, which may reflect recall bias, and the presence of arthritis was not confirmed by a health professional; it may be difficult to attribute work limitation to arthritis, especially if the person is suffering from multiple chronic conditions; the wording of the questionnaire did not distinguish between those who could not work and those whose work was simply affected in some way.

Nonetheless the size of the study enabled the authors to develop US national prevalence estimates for AAWL, the results of which can be used as a benchmark for future studies and to help monitor progress in reducing the number of people with AAWL. In addition, by identifying characteristics associated with AAWL, the study may be useful in developing timely interventions for those at risk of work disability. This could have a major impact not just on these individuals, but on society at large. Indirect costs of arthritis have been estimated at $35.1 billion for 1997, and the authors note that "protecting workers from disability, injury, and prolonged negative effects of illness makes simple social and economic sense."

The authors note that future research on public health and arthritis management could address what types of work people with arthritis are unable to do, which groups are more affected and why, and how interventions can be tested, targeted and delivered. They point out that describing and addressing work limitations is an important part of preventing disability. They conclude, "This initial characterization of AAWL will aid in informing research and the development and evaluation of interventions to decrease work limitation experienced by individuals with arthritis."

Arthritis-attributable work limitation affects nearly 7 million U.S. adults, disproportionately affects minority groups, and presents opportunities to reduce arthritis impact by implementing effective interventions to preserve and improve function.