Galarraga B, Khan F, Kumar P, Pullar T, Belch J J F
Institute of Cardiovascular Research, Vascular and Inflammatory Diseases Research Unit, University Division of Medicine and Therapeutics, Ninewells Hospital and Medical School, Dundee DD1 9SY, UK.
Rheumatology (Oxford). 2008 Dec;47(12):1780-4. doi: 10.1093/rheumatology/ken386. Epub 2008 Oct 14.
RA is a chronic autoimmune inflammatory condition associated with increased cardiovascular morbidity and mortality. Endothelial dysfunction, a marker of early atherosclerotic disease, occurs in some inflammatory diseases but this relationship has not been previously explored within the microvasculature of patients with RA. We therefore assessed forearm microvascular endothelial function in patients with RA and determined its relationship to RA disease activity and inflammation.
A total of 128 RA patients with no previous history of cardiovascular disease were evaluated. Endothelium-dependent and -independent forearm skin microvascular function was measured using laser Doppler imaging after iontophoretic delivery of acetylcholine (ACh) and sodium nitroprusside (SNP), respectively. Parameters of RA disease activity and inflammation were also checked.
There was a significant negative correlation between the level of inflammation measured by log(10)CRP and maximum vasodilatation measured by peak ACh response (r(2) = -0.209, P = 0.018, Pearson correlation test). In a multiple regression model, age (beta = -0.449, P < 0.0001) and log(10)CRP (beta = -0.193, P = 0.026) were independently negatively associated with ACh responses. When RA patients were sub-divided according to their systemic inflammatory status (CRP > 10 mg/l vs CRP </= 10 mg/l), the high CRP group showed lower vasodilator responses to ACh [P = 0.018, analysis of variance (ANOVA)] and SNP (P = 0.05, ANOVA) than the low CRP group.
In this large cross-sectional study, we found for the first time systemic inflammation (CRP) to be independently associated with microvascular dysfunction in patients with RA. This strong correlation was independent of other conventional vascular risk factors.
类风湿关节炎（RA）是一种慢性自身免疫性炎症性疾病，与心血管疾病发病率和死亡率增加相关。内皮功能障碍是早期动脉粥样硬化疾病的一个标志物，在一些炎症性疾病中会出现，但此前尚未在RA患者的微血管系统中探讨这种关系。因此，我们评估了RA患者的前臂微血管内皮功能，并确定其与RA疾病活动度和炎症的关系。
共评估了128例既往无心血管疾病史的RA患者。分别在离子电渗法给予乙酰胆碱（ACh）和硝普钠（SNP）后，使用激光多普勒成像测量内皮依赖性和非依赖性前臂皮肤微血管功能。还检查了RA疾病活动度和炎症的参数。
通过log(10)CRP测量的炎症水平与通过ACh峰值反应测量的最大血管扩张之间存在显著负相关（r(2)= -0.209，P = 0.018，Pearson相关检验）。在多元回归模型中，年龄（β = -0.449，P < 0.0001）和log(10)CRP（β = -0.193，P = 0.026）与ACh反应独立呈负相关。当根据全身炎症状态（CRP > 10 mg/l与CRP≤10 mg/l）对RA患者进行亚组划分时，高CRP组对ACh的血管扩张反应[P = 0.018，方差分析（ANOVA）]和对SNP的反应（P = 0.05，ANOVA）均低于低CRP组。
在这项大型横断面研究中，我们首次发现全身炎症（CRP）与RA患者的微血管功能障碍独立相关。这种强相关性独立于其他传统血管危险因素。
