慢性阻塞性肺疾病的高分辨率CT分型及其与白细胞介素-6的关系

目的 探讨高分辨率CT评价COPD的方法,并依此判断COPD影像学分型及其与气道炎症的关系.方法 收集2007年11月至2009年3月上海交通大学医学院附属瑞金医院收治的84例COPD稳定期患者,其中男59例,女25例,年龄34～81岁,平均年龄(67±11)岁,进行胸部高分辨率CT扫描和肺功能检查,根据高分辨率CT影像中肺气肿程度和支气管管壁增厚情况进行分型,并测定其中30例的呼出气冷凝液中白细胞介素(IL)-6的水平.结果 根据胸部高分辨率CT表现,将COPD患者分为3种类型:(1)A型(34例):无或轻微肺气肿,合并或不合并支气管管壁增厚;(2)E型(23例):有肺气肿,无支气管管壁增厚;(3)M型(27例):有肺气肿和支气管管壁增厚.A型患者的平均体重指数为(25.1±4.4)kg/m~2,明显高于E型和M型[(22.5±4.1)和(21.3±3.4)kg/m~2],差异有统计学意义(F=6.732,P＜0.01).A型中轻度呼吸困难者(15/34例)明显多于E型(2/23例)和M型(6/27例),差异有统计学意义(χ~2=9.097,P＜0.05).E型的中、重度咳痰者(均为0/23例)明显少于A型(2/34)和M型(4/27),差异有统计学意义(χ~2=8.702,P＜0.05).A型患者的FEV_1/FVC和FEV_1占预计值%分别为(67±11)%和(72±24)%,明显高于E型[(53±14)%和(52±26)%]和M型[(53±14)%和(51±25)%],差异均有统计学意义(F值分别为10.252和6.508,均P＜0.01).A型患者的深吸气量/肺总量为(41±17)%,明显高于E型和M型[(33±13)%和(28±13)%],差异有统计学意义(F=5.964,P＜0.01).A型患者的残气容积/肺总量为(37±9)%,明显低于E型和M型[(44±10)%和(45±8)%],差异有统计学意义(F=6.954,P＜0.01).M型患者的呼出气冷凝液中IL-6水平为(25.6±4.4)ng/L,明显高于A型和E型[(19.9±6.3)和(16.7±2.1)ng/L],差异有统计学意义(F=7.749,P＜0.01).结论 COPD高分辨率CT3种分型的临床特征不同,且与肺功能及气道炎症相关.

Characteristics of chronic obstructive pulmonary disease phenotypes based on high-resolution CT and the relationship with interleukin-6

Objective To classify the high-resolution CT (HRCT) phenotypes of COPD,and to investigate the clinical characteristics of various phenotypes and the relationship with airway inflammation.Methods Chest HRCT and pulmonary function tests were performed in 84 COPD patients.The patients were classified into 3 phenotypes according to the visual HRCT findings.Exhaled breath condensate was gathered from 30 patients and the interleukin (IL)-6 level was measured by ELISA.Results The COPD patients were classified into 3 phenotypes:Phenotype A,absence of emphysema,with or without bronchial wall thickening (n = 34);Phenotype E,emphysema without bronchial wall thickening (n = 23);and Phenotype M,emphysema with bronchial wall thickening (n = 27).The 3 phenotypes of COPD showed different characteristics in several aspects.Patients with phenotype A showed a higher body mass index [(25.1±4.4) kg/m~2 vs phenotype E (22.5±4.1) kg/m~2 and phenotype M (21.3±3.4) kg/m~2,F =6.732,P ＜ 0.01].The prevalence of patients with milder dyspnea was lower in phenotype A compared with others (15/34) vs phenotype E (2/23) and phenotype M (6/27),X~2 = 9.097,P ＜ 0.05.The patients who complained of severe expectoration in phenotype E were fewer than those in other groups (0/23) vs phenotype A (2/34) and phenotype M (4/27),X~2 =8.702,P＜0.05.The FEV_1/FVC and FEV_1 % in phenotype M[(53±14)% and (51±25)%]were significantly lower as compared with those in other phenotypes[(67±11)% and (72±24)% in phenotype A,and (53±14)% and (52±26)% in phenotype E],F =10.252,F=6.508,P ＜ 0.01.The ratio of inspiratory capacity to total lung capacity (IC/TLC) in phenotype A was higher[phenotype A (41±17)%,phenotype E (33±13)%,pheuotype M (28±13) %,F = 5.964,P ＜ 0.01],while the ratio of residual volume to total lung capacity (RV/TLC)was lower[phenotype A (37±9) %,phenotype E (44±10) %,phenotype M (45±8) %,F = 6.954,P ＜0.01].Patients with different phenotypes showed various levels of IL-6 in exhaled breath condensate [phenotype A (19.9±6.3) ng/L,phenotype E (16.7±2.1) ng/L,phenotype M (25.6±4.4) ng/L,F =7.749,P ＜0.01].Conclusion Various morphological phenotypes of COPD based on HRCT showed different clinical characteristics and airway inflammation.