Department of Rheumatology, Tokyo Medical University Hospital, 6-7-1 Nishi-Shinjuku, Shinjuku, Tokyo, 160-0023, Japan.
Rheumatic Disease Center, Kurashiki Medical Center, 250 Bakuro, Kurashiki, Okayama, 710-8522, Japan.
BMC Musculoskelet Disord. 2019 Jan 18;20(1):30. doi: 10.1186/s12891-019-2418-2.
Previous studies suggest that RA activity is sensitive to seasonal changes. This study explored the influence of season on RA activity, particularly the distribution of affected joints, using a nationwide database in Japan.
We investigated 12,839 patients whose RA activity was recorded in spring (n = 3250), summer (n = 916), fall (n = 1021), and winter (n = 7652). Disease activity score (DAS) 28-CRP, simplified disease activity index (SDAI), and clinical disease activity index (CDAI) were used as indices of disease activity. Disease activity was also assessed according to DAS28-CRP scores (remission, low, moderate, or high). The affected joint distribution was investigated using novel joint indices (x, y, z), where x and y are indices for the upper and lower joints, respectively, and z is the index for large joint predominance.
Mean DAS28-CRP and median SDAI and CDAI scores were highest in spring and lowest in fall. There was a significant difference in the DAS28-CRP for fall versus spring and winter. Fall was associated with a higher remission rate, and spring and winter with high and moderate RA activity, respectively. Significant differences in x, y, SDAI, and CDAI scores were found for spring versus summer, fall, and winter, in addition to fall versus winter (except in y). There was no seasonal difference in the z index.
RA activity in the upper and lower extremities may be highest in spring, followed by winter. Seasonal changes should be considered in patients with RA to better understand their symptoms.
先前的研究表明，类风湿关节炎（RA）的活动度对季节变化敏感。本研究利用日本全国性数据库探讨了季节对 RA 活动度的影响，特别是受累关节的分布。
我们调查了 12839 例 RA 活动度记录于春季（n=3250）、夏季（n=916）、秋季（n=1021）和冬季（n=7652）的患者。疾病活动评分（DAS）28- CRP、简化疾病活动指数（SDAI）和临床疾病活动指数（CDAI）被用作疾病活动的指标。根据 DAS28-CRP 评分（缓解、低、中或高）评估疾病活动。采用新的关节指数（x、y、z）评估受累关节分布，其中 x 和 y 分别为上肢和下肢的指数，z 为大关节优势指数。
春季 DAS28-CRP 均值和 SDAI 及 CDAI 中位数最高，秋季最低。秋季 DAS28-CRP 与春季和冬季比较有显著差异。秋季缓解率较高，而春季和冬季 RA 活动度分别为高和中。春季与夏季、秋季和冬季，以及秋季与冬季（y 除外）的 x、y、SDAI 和 CDAI 评分比较均有显著差异。z 指数无季节性差异。
上下肢 RA 活动度春季最高，其次是冬季。在评估 RA 患者时应考虑季节变化，以更好地了解其症状。
