It turns out that patients with rheumatoid arthritis appear to have higher disease activity during the spring season relative to the fall season, based on subjective and objective disease measures.
To determine whether a seasonal fluctuation in disease severity exists among patients with rheumatoid arthritis (RA), researchers examined data from 1,665 patients with RA who participated in a large, observational cohort study conducted in Japan from October 2000 to April 2005. The majority of the patients (81.7%) were female, the mean age of the patients was 57.2 years, and the mean disease duration was 9.9 years.
Ten criteria were used to assess disease activity, including objective, subjective, patient-assessed, and physician-assessed measures. Evaluations were made each spring and fall during the study period.
The results showed higher disease activity in the spring for almost all measures.
In addition to clinical measures of disease, laboratory measures of disease activity including the erythrocyte sedimentation rate (sed rate), C-reactive protein, and rheumatoid factor were also significantly elevated in the spring compared with the fall.
The implications of the research are difficult to fully establish. However, it is clear that examining patients during different times of the year may lead to different results. Seasonal variations in symptoms should be taken into account when planning changes in treatment. Patients with RA should be warned about the possible seasonal variations that can occur.
(N. Iikuni, A. Nakajima, E. Inoue, E. Tanaka, H. Okamoto, M. Hara, T. Tomatsu, N. Kamatani and H. Yamanaka. What's in season for rheumatoid arthritis patients? Seasonal fluctuations in disease activity Rheumatology. January 2007).