Department of Rheumatology, Clinical Research Center for Rheumatic Disease, NHO Kumamoto Saishunsou National Hospital, 2659 Suya, Kohshi, Kumamoto, 861-1196, Japan.
Mod Rheumatol. 2011 Apr;21(2):164-73. doi: 10.1007/s10165-010-0376-5. Epub 2010 Dec 7.
This work was intended to evaluate the prevalence of obstructive small-airway disease in patients with rheumatoid arthritis (RA) and its association with clinical characteristics. Pulmonary function testing (PFT) and high-resolution computed tomography (HRCT) were performed on 189 consecutive RA patients. Each case was diagnosed based on abnormal HRCT findings. We defined obstructive dysfunction of small airways as a forced expiratory flow from 25% to 75% of vital capacity (FEF(25-75)) value >1.96 residual standard deviation (RSD) below predicted values. We found 19 patients (10.1%) with an interstitial pneumonia (IP) pattern and 15 (7.9%) with a bronchiolitis pattern; the other 155 (82.0%) had no abnormal HRCT patterns. In patients with neither abnormal pattern, median values of percentage predicted for carbon monoxide diffusing capacity (DL(CO)) and ratio of DL(CO) to alveolar ventilation (DLco/VA) were within the normal range, but median FEF(25-75), forced expiratory flow at 25% of vital capacity (V(25)), and V(25)/height were <70% of predicted values. Forty-seven patients (30.3%) in this group had obstructive small-airway dysfunction. Multivariate logistic regression analysis indicated that this type of abnormality is strongly associated with respiratory symptoms [odds ratio (OR) 5.18; 95% confidence interval (CI) 1.70-15.75; p = 0.012), smoking history (OR 2.78; 95% CI 1.10-6.99; p = 0.03), and disease duration >10 years (OR 2.86; 95% CI 1.27-6.48; p = 0.012). Parenchymal micronodules, bronchial-wall thickening, and bronchial dilatation on HRCT scans were also predictive factors for abnormal FEF(25-75), although these morphological changes were too limited for us to diagnose these patients with the bronchiolitis pattern. Obstructive dysfunction of small airways is apparently common among RA patients, even among those with neither the IP nor the bronchiolitis pattern on HRCT scans. Factors significantly associated with abnormal FEF(25-75) are respiratory symptoms, smoking history, and RA duration.
本研究旨在评估类风湿关节炎（RA）患者中阻塞性小气道疾病的患病率及其与临床特征的关系。对 189 例连续的 RA 患者进行了肺功能检测（PFT）和高分辨率计算机断层扫描（HRCT）。每个病例均根据异常的 HRCT 结果进行诊断。我们将小气道阻塞性功能障碍定义为用力呼气流量从 25%肺活量到 75%肺活量（FEF（25-75））值大于预测值的 1.96 残差标准差（RSD）。我们发现 19 例（10.1%）患者存在间质性肺炎（IP）模式，15 例（7.9%）患者存在细支气管炎模式；其余 155 例（82.0%）患者 HRCT 模式无异常。在无异常模式的患者中，一氧化碳弥散量（DL（CO））的百分比预测值和 DL（CO）与肺泡通气量（DLco/VA）的比值中位数均在正常范围内，但 FEF（25-75）、25%肺活量时的用力呼气流量（V（25））和 V（25）/身高中位数均<70%预测值。该组中有 47 例（30.3%）患者存在阻塞性小气道功能障碍。多变量逻辑回归分析表明，这种类型的异常与呼吸系统症状密切相关[比值比（OR）5.18；95%置信区间（CI）1.70-15.75；p=0.012]、吸烟史（OR 2.78；95%CI 1.10-6.99；p=0.03）和病程>10 年（OR 2.86；95%CI 1.27-6.48；p=0.012）。HRCT 扫描上的实质微结节、支气管壁增厚和支气管扩张也是异常 FEF（25-75）的预测因素，尽管这些形态学改变过于局限，我们无法诊断这些细支气管炎模式患者。RA 患者中，阻塞性小气道功能障碍显然很常见，即使在 HRCT 扫描未见间质性肺炎或细支气管炎模式的患者中也是如此。与异常 FEF（25-75）显著相关的因素是呼吸系统症状、吸烟史和 RA 病程。
