类风湿性关节炎患者静脉血栓风险增高

柏林——在欧洲风湿病大会(ECR)上展示的2项大型研究的结果提示，类风湿性关节炎(RA)患者面临静脉血栓栓塞(VTE)风险中度增高，并在患RA多年后风险仍不见降低。

美国布里格姆妇女医院的风湿病专家Seoyoung C. Kim医生及其同事开展了一项回顾性队列研究，共纳入22,143例RA患者和88,572名年龄及性别匹配的对照者。所有受试者基线时均无恶性疾病或VTE病史。数据来自美国一项大型商业保险计划。

结果显示，在平均2年的随访期间(开始于RA患者首次接受缓解疾病抗风湿药物处方治疗之时)，RA组和对照组深静脉血栓或肺栓塞的发生率分别为1.2%和0.5%。RA患者的发生率为6.1例/1,000人-年，是对照组的2.4倍。RA组肺栓塞发生率为对照组的2.7倍，深静脉血栓发生率为对照组的2.2倍。经校正已知的VTE风险因素(包括手术、住院和心血管疾病)后，RA仍与VTE风险中度增高相关，较对照组患者增高40%。

研究者认为RA患者的VTE风险中度增高可能与RA的全身性炎症状态有关。

瑞典卡罗林斯卡研究所的Marie Holmqvist博士展示了一项前瞻性、以人群为基础的队列研究，共纳入1997~2009年间新诊断为RA的8,077例患者和203,329名对照者。

结果显示，在总共43,178患者-年的前瞻性随访中，共有84例RA患者被诊断为肺栓塞。相当于1.9例/1,000患者-年，而对照组发生率为1.1例/1,000患者-年。在诊断RA后1年内，肺栓塞风险明显增加，以后风险增加保持不变。在诊断RA后的1~4年间，RA组的肺栓塞风险为一般人群对照者的1.8倍。在诊断RA后5~9年间，RA患者的风险为对照组的2倍，在诊断RA后的10~15年间，RA患者的肺栓塞风险为对照组的1.9倍，但仅有很少的受试者接受了如此长期的随访。

Holmqvist博士还指出，因任何原因住院的对照者在下一年中发生肺栓塞的风险为未住院对照者的5.4倍，住院RA患者下一年肺栓塞风险的增加程度与住院的对照患者相同。也就是说，RA未在住院之外进一步增加肺栓塞风险。

研究者总结认为，RA患者的肺栓塞风险中度增高，且多年保持不变。对于住院患者，RA不会额外增加肺栓塞风险。

Holmqvist博士和Kim医生均披露无相关利益冲突，且无一研究接受商业资助。

爱思唯尔  版权所有

By: BRUCE JANCIN, Internal Medicine News Digital Network

BERLIN– Rheumatoid arthritis patients face a moderately elevated risk of venous thromboembolism that continues unabated for many years, according to findings from two large studies presented at the European Congress of Rheumatology.

Dr. Seoyoung C. Kim offered a retrospective cohort study involving 22,143 patients with rheumatoid arthritis (RA) and 88,572 age- and sex-matched controls. None of the subjects had a baseline history of malignancy or venous thromboembolism (VTE). The data came from a large U.S. commercial insurance plan.

During a mean follow-up of 2 years (starting when the RA patients received their first prescription for a disease-modifying antirheumatic drug), deep vein thrombosis or pulmonary embolism occurred in 1.2% of RA patients and 0.5% of controls. The incidence among RA patients was 6.1 cases per 1,000 person-years, a rate 2.4-fold greater than in controls. The pulmonary embolism rate was 2.7 times higher than in controls, whereas the deep vein thrombosis rate was 2.2-fold higher, according to Dr. Kim of Brigham and Women’s Hospital, Boston, where she is a rheumatologist.

After adjustment for known risk factors for VTE, including surgery, hospitalization, and cardiovascular disease, the VTE risk associated with having RA remained moderately elevated, with a 40% increase compared with controls.

The mechanism underlying this increased risk is believed to hinge upon the systemic inflammation that is a central feature of RA. This inflammation is thought to predispose to thrombus formation, up-regulation of procoagulants, down-regulation of anticoagulants, and suppression of fibrinolysis, Dr. Kim noted.

Dr. Marie Holmqvist presented a prospective population-based cohort study including 8,077 patients who were newly diagnosed with RA during 1997-2009, as well as 203,329 controls.

In all, 84 RA patients were diagnosed with a pulmonary embolism during 43,178 person-years of prospective follow-up. That translated to an incidence of 1.9 cases per 1,000 person-years, compared with 1.1 cases per 1,000 person-years among controls.

The increased risk of pulmonary embolism was evident 1 year after diagnosis of RA and remained unchanged thereafter. In the period 1-4 years after diagnosis of RA, the RA group had a 1.8-fold greater risk of pulmonary embolism than did controls drawn from the general population. During years 5-9, the risk was increased 2.0-fold, and in years 10-15 the risk of pulmonary embolism in RA patients was 1.9-fold greater than in controls, although only a small number of subjects were followed that long.

Control subjects who were hospitalized for any reason had a 5.4-fold increased risk of pulmonary embolism for the next year, compared with nonhospitalized controls. The risk of pulmonary embolism in hospitalized RA patients was elevated for the next year to the same extent as in hospitalized controls. In other words, having RA didn’t pile on additional risk beyond hospitalization itself, according to Dr. Holmqvist of the Karolinska Institute, Stockholm.

Dr. Holmqvist and Dr. Kim reported having no financial conflicts. Neither study had commercial sponsorship.