Arthritis is the most common form of joint disease. Several powerful risk factors are major trauma, repetitive joint use, and age. Arthritis is diagnosed according to a combination of clinical features and radiographic findings. Arthralgia, which is a self-reported symptom of arthritis, refers to painful joints. In the absence of other clinical features and radiographic findings, arthralgias are not necessarily diagnostic of arthritis.
Arthralgias were one of 12 primary health outcome measures studied by Eisen and colleagues (2005). They conducted medical evaluations in phase III of VA’s nationally representative, population-based study. From 1999-2001, 1,061 deployed and 1,128 nondeployed veterans were evaluated. They had been randomly selected from 11,441 deployed and 9,476 nondeployed veterans who had participated in the phase I questionnaire in 1995 (Kang et al. 2000). Researchers were blinded to deployment status. Arthralgias were defined as persistent and clinically significant bone or joint symptoms with or without joint effusion, and treatment with anti-inflammatory agents, narcotic pain medications, or nonnarcotic pain medications. There was no statistically significant difference in arthralgias between deployed and nondeployed veterans (OR 1.15, 95% CI 0.70-1.89).
One study limitation was that despite three recruitment waves, the participation rate in the 2005 study was low: only 53% of Gulf War veterans and 39% of nondeployed veterans participated. To determine nonparticipation bias, the authors obtained previously collected findings on participants and nonparticipants from the DOD Manpower Data Center and gathered sociodemographic and self-reported health findings from the 1995 VA study (Kang et al. 2000). Both deployed and nondeployed participants were more likely than nonparticipants to report arthritis of any kind. See Table 5.16 for a summary of the studies reviewed in this section.
Two other studies examined differences in prevalence of arthritis, but they relied on self-reporting. Kang et al. (2000), using a stratified random-sampling method, compared data from the DOD Defense Manpower Data Center on 693,826 Gulf War deployed veterans and 800,680 non-Gulf War veterans, and asked about arthritis as a self-reported condition. They found a significant difference in such reporting between Gulf War-deployed and non-Gulf War deployed veterans (22.5% vs 16.7%, rate difference of 5.87, 95% CI 5.74-6.00). Gray et al. (2002) looked at 3,831 Gulf War deployed veterans, 4,933 veterans deployed elsewhere, and 3,104 nondeployed Seabees. The authors found an increase in reporting of arthritis among Gulf War than among Seabees deployed elsewhere (5.87% vs 4.42%). The latter, in turn, were similar to other nondeployed Seabees (4.42% vs 4.38%). The OR for Gulf War veterans vs veterans deployed elsewhere was 1.44 (95% CI 1.17-1.76), and that for Gulf War-deployed vs non-deployed veterans was 1.63 (95% CI 1.29-2.08).