Clinic of Orthopaedics, Rheumatology and Dermatology, St Olavs University Hospital, Trondheim, Norway.
Department of Clinical and Molecular Medicine, NTNU - Norwegian University of Science and Technology, Trondheim, Norway.
RMD Open. 2021 Mar;7(1). doi: 10.1136/rmdopen-2020-001545.
Investigate if low cardiorespiratory fitness (CRF) was associated with and acted as a mediator of excess all-cause mortality rate in persons suffering from rheumatoid arthritis (RA) compared with the general population.
All-cause mortality was analysed using Cox regression modelling in patients with RA (n=348) and controls (n=60 938) who took part in the second (1995-1997) and third (2006-2008) waves of the longitudinal population-based Trøndelag Health Study in Norway. A mediation analysis was performed to investigate if excess relative risk of mortality in RA was mediated by low estimated CRF (eCRF).
During the follow-up until 31 December 2018 (mean 19.3 years), the mortality rate among patients with RA (n=127, 36.5%) was higher than among controls (n=12 942, 21.2%) (p<0.001). Among controls and patients with RA, 51% and 26%, respectively, had eCRF above the median for their age and sex (p<0.001). The final Cox model included RA status and eCRF, adjusted for hypertension, body mass index, smoking, cholesterol, diabetes and creatinine. eCRF below median for sex and age category was associated with increased mortality (p<0.001). The total excess relative risk of mortality in patients with RA was 28% (95% CI 2% to 55%, p=0.035), in which RA itself contributed 5% and the direct and indirect contributions of low eCRF accounted for 23%.
Low eCRF was an important mediator of the increased all-cause mortality rate found in RA. Our data indicate that patients with RA should be given advice to perform physical activity that increases CRF, along with optimised treatment with antirheumatic drugs, from the time of diagnosis.
研究与普通人群相比，患有类风湿关节炎（RA）的人群低心肺功能适应性（CRF）是否与全因死亡率过高相关，并充当其中介因素。
使用 Cox 回归模型分析了参加挪威特隆赫姆健康研究纵向人群研究第二（1995-1997 年）和第三（2006-2008 年）波次的 348 名 RA 患者和 60938 名对照者的全因死亡率。进行中介分析以研究 RA 患者的超额死亡风险是否由低估计 CRF（eCRF）介导。
在截至 2018 年 12 月 31 日的随访期间（平均 19.3 年），RA 患者（n=127，36.5%）的死亡率高于对照组（n=12942，21.2%）（p<0.001）。在对照组和 RA 患者中，分别有 51%和 26%的人的 eCRF 高于其年龄和性别中位数（p<0.001）。最终的 Cox 模型包括 RA 状态和 eCRF，调整了高血压、体重指数、吸烟、胆固醇、糖尿病和肌酐。eCRF 低于性别和年龄类别中位数与死亡率增加相关（p<0.001）。RA 患者的总超额死亡风险为 28%（95%CI 2%至 55%，p=0.035），其中 RA 本身占 5%，低 eCRF 的直接和间接贡献占 23%。
低 eCRF 是 RA 患者全因死亡率升高的一个重要中介因素。我们的数据表明，RA 患者应在确诊时就接受建议，进行能提高 CRF 的体力活动，并接受优化的抗风湿药物治疗。
