Icen Murat, Nicola Paulo J, Maradit-Kremers Hilal, Crowson Cynthia S, Therneau Terry M, Matteson Eric L, Gabriel Sherine E
Department of Health Sciences Research, Mayo Foundation, 200 First St. SW, Rochester, MN 55905, USA.
J Rheumatol. 2009 Jan;36(1):50-7. doi: 10.3899/jrheum.080091.
Features of systemic lupus erythematosus (SLE) are commonly observed in patients with rheumatoid arthritis (RA). However, their frequency and clinical significance are uncertain. We examined the frequency of SLE features in RA and their effect on overall mortality.
We assembled a population-based incidence cohort of subjects aged >or=18 years first diagnosed with RA [1987 American College of Rheumatology (ACR) criteria] between 1955 and 1995. Information regarding disease characteristics, therapy, comorbidities, and SLE features (1982 ACR criteria) were collected from the complete inpatient and outpatient medical records. Cox regression models were used to estimate the mortality risk associated with lupus features.
The study population comprised 603 subjects with incident RA (mean age 58 yrs, 73% women) with a mean followup time of 15 years. By 25 years after RA incidence, >or=4 SLE features were observed in 15.5% of the subjects with RA. After adjustment for age and sex, occurrence of >or=4 SLE features was associated with increased overall mortality [hazard ratio (HR) 5.54, 95% confidence interval (CI) 3.59-8.53].With further adjustment for RA characteristics, therapy, and comorbidities, the association weakened but remained statistically significant (HR 2.56, 95% CI 1.60-4.08). After adjustment for age, sex, RA characteristics, therapy, and comorbidities, thrombocytopenia (2.0, 95% CI 1.2, 3.1) and proteinuria (1.8, 95% CI 1.3, 2.6) were significantly associated with mortality.
SLE features were common in RA, given sufficient observation time. Subjects with RA who developed >or=4 SLE features had an increased risk of death. Proteinuria and thrombocytopenia were individually associated with an increased mortality risk.
类风湿关节炎（RA）患者中常可观察到系统性红斑狼疮（SLE）的特征。然而，其出现频率及临床意义尚不确定。我们研究了RA患者中SLE特征的出现频率及其对总死亡率的影响。
我们纳入了一个基于人群的发病队列，对象为1955年至1995年间首次诊断为RA（依据1987年美国风湿病学会（ACR）标准）且年龄≥18岁的受试者。从完整的住院和门诊病历中收集有关疾病特征、治疗、合并症及SLE特征（依据1982年ACR标准）的信息。采用Cox回归模型估计与狼疮特征相关的死亡风险。
研究人群包括603例新发RA患者（平均年龄58岁，73%为女性），平均随访时间为15年。至RA发病后25年时，15.5% 的RA患者出现了≥4项SLE特征。在对年龄和性别进行校正后，出现≥4项SLE特征与总死亡率增加相关 [风险比（HR）5.54，95%置信区间（CI）3.59 - 8.53]。在进一步对RA特征、治疗及合并症进行校正后，该关联有所减弱但仍具有统计学意义（HR 2.56，95% CI 1.60 - 4.08）。在对年龄、性别、RA特征、治疗及合并症进行校正后，血小板减少（HR 2.0，95% CI 1.2，3.1）和蛋白尿（HR 1.8，95% CI 1.3，2.6）与死亡率显著相关。
给予足够的观察时间后，SLE特征在RA中很常见。出现≥4项SLE特征的RA患者死亡风险增加。蛋白尿和血小板减少分别与死亡率增加相关。
