Department of Orthopaedic Surgery, University of California, San Diego, La Jolla, California, USA
Department of Medicine, Division of Nephrology-Hypertension, University of California, San Diego, La Jolla, California, USA.
BMJ Open. 2021 Sep 14;11(9):e050883. doi: 10.1136/bmjopen-2021-050883.
Physical activity (PA) in preclinical rheumatoid arthritis (RA) is associated with lower RA risk and disease severity. As joint signs and symptoms of inflammatory arthritis serve as a barrier to PA in RA, it is important to consider whether they affect PA in the time prior to RA. Therefore, we investigated whether joint swelling, stiffness or pain were associated with PA in first-degree relatives (FDRs) of patients with RA, a population at higher risk for future RA.
Prospective study design.
We recruited FDRs of patients with RA from academic centres, Veterans' hospitals and rheumatology clinics or through responses to advertising from six sites across the USA.
We evaluated associations of joint stiffness, joint swelling and joint pain with PA time in 268 FDRs with ≥2 visits over an average 1.2 years. Clinicians confirmed joint swelling. Participants self-reported joint stiffness and/or pain.
PA during a typical 24-hour day was quantified via questionnaire, weighted to reflect metabolic expenditure, where 24 hours was the minimum PA time. Linear mixed models evaluated associations between symptoms and change in PA over time, adjusting for age, sex, race, body mass index, smoking and RA-related autoantibodies.
Average weighted PA time was 37±7 hours. In the cross-sectional analysis, PA time was 1.3±0.9 hours higher in FDRs reporting joint pain (p=0.15); and 0.8±1.6 and 0.4±1 hours lower in FDRs with joint swelling (p=0.60) and stiffness (p=0.69), respectively. Longitudinally, adjusting for baseline PA time, baseline symptoms were not significantly associated with changes in PA time. However, on average over time, joint stiffness and pain were associated with lower PA time (p=0.0002, p=0.002), and joint swelling was associated with higher PA time (p <0.0001).
Baseline symptoms did not predict future PA time, but on average over time, joint symptoms influenced PA time.
在临床前类风湿关节炎（RA）中，身体活动（PA）与较低的 RA 风险和疾病严重程度相关。由于炎性关节炎的关节体征和症状是 RA 中 PA 的障碍，因此重要的是要考虑它们是否会影响 RA 之前的 PA。因此，我们研究了 RA 患者的一级亲属（FDR）中关节肿胀，僵硬或疼痛是否与 PA 相关，该人群处于更高的未来 RA 风险中。
前瞻性研究设计。
我们从学术中心，退伍军人医院和风湿病诊所招募了 RA 患者的 FDR，或者通过在美国六个地点的广告回应招募。
我们评估了 268 名 FDR 的关节僵硬，关节肿胀和关节疼痛与平均 1.2 年期间的 PA 时间之间的关联，这些 FDR 至少有 2 次就诊。临床医生确认了关节肿胀。参与者自我报告了关节僵硬和/或疼痛。
通过问卷定量评估 24 小时内 PA 时间，通过加权反映代谢支出，其中 24 小时是 PA 时间的最小值。线性混合模型评估了症状与随时间变化的 PA 之间的关联，调整了年龄，性别，种族，体重指数，吸烟和 RA 相关自身抗体。
平均加权 PA 时间为 37±7 小时。在横断面分析中，报告关节疼痛的 FDR 的 PA 时间高出 1.3±0.9 小时（p=0.15）；关节肿胀（p=0.60）和僵硬（p=0.69）的 FDR 分别低 0.8±1.6 和 0.4±1 小时。纵向调整基线 PA 时间后，基线症状与 PA 时间的变化无显著相关性。然而，平均而言，随着时间的推移，关节僵硬和疼痛与较低的 PA 时间相关（p=0.0002，p=0.002），而关节肿胀与较高的 PA 时间相关（p<0.0001）。
基线症状不能预测未来的 PA 时间，但随着时间的推移，关节症状会影响 PA 时间。
