Clinical characteristics and significance of COPD patients with frequent and non-frequent exacerbations in stable stage in Third class and Grade-A hospitals of Shanghai area

Objective To investigate and compare the clinical characteristics of stable chronic obstructive pulmonary disease (COPD) patients in the frequent exacerbation (FE) and non frequent exacerbation (NFE) groups from the several Third class and Grade-A hospitals of Shanghai area, and analyze their clinical significance. Methods The clinical symptoms score, pulmonary lung function results, serum markers and the distribution of comorbidities of 113 patients diagnosed of stable COPD from October 2018 to June 2019 were analyzed and summarized in a retrospective, multicenter and cross-sectional survey.The patients were divided into FE group(n=60) and NFE group (n=53) and compared the differences between the two groups. Results (1)General characteristics: The mean age was (67.84±8.66) years old.There was no significant difference in age, course of disease and smoking exposure between the two groups.BMI in FE group was lower than that of in NFE group [(22.49±3.32) kg/m2 vs (24.07±3.58) kg/m2, t=2.431, P=0.017]. The CAT score[(17.30±7.59) vs (11.38±6.38), t=-4.458, P<0.001], SGRQ score[(37.29±14.82) vs (23.18±12.57), t=-5.288, P<0.001], BODE index[(3.96±1.97) vs (3.05±2.25), t=-2.061, P<0.042], HAMA score[14(12) vs 9(8), Z=-2.183, P=0.029], and the morbidity of GOLD3-4 patients (63.6% vs 43.1%, χ2=4.473, P=0.034) in FE group were all higher than those of in NFE group, there were significant differences in those results.(2)Pulmonary function: The results of FEV1, FEV1%pred, FVC%pred, FEF25-75, FEF25-75% pred, FEF50, FEF50% pred, DLCO%pred before bronchodilator inhalation in FE group were lower than those of NFE group[(1.14±0.47) L vs (1.39±0.64) L, t=2.314, P=0.023; (43.82±16.50)% vs (53.13±20.88)%, t=2.534, P=0.013; (69.06±17.85)% vs (76.65±19.14)%, t=2.110, P=0.037; (0.49±0.29) L vs (0.66±0.40) L, t=2.569, P=0.012; (16.50±8.69)% vs (21.81±12.58)%, t=2.723, P=0.008; (0.60±0.41) L vs (0.84±0.58) L, t=2.374, P=0.020; (15.97±9.72)% vs (22.14±13.91)%, t=2.652, P=0.009; and (54.35±21.90)% vs (65.20±25.67)%, t=2.133, P=0.036 respectivly]. The results of FEV1/FVC, FEV1, FEV1%pred, FEF25-75, FEF50%pred after bronchodilator inhalation in FE group were all lower than those of NFE group[(49.38±12.16)% vs (55.57±11.71)%, t=2.508, P=0.014; (1.32±0.52) L vs (1.57±0.65) L, t=2.059, P=0.042; (50.12±17.18)% vs (60.22±20.57)%, t=2.591, P=0.011; (0.59±0.37) L vs (0.75±0.42)L, t=2.026, P=0.046; and (19.99±12.12)% vs (26.23±14.81)%, t=2.242, P=0.027 respectivly], there were statistically significant difference in above results.(3) Serum markers: the results of hemoglobin concentration (HGB) in FE group was lower than that of in NFE group[142(21) g/L vs 148(18) g/L, Z=-2.159, P=0.031], and the result of serum total IgE was higher than that in NFE group[166 (339) U/ml vs 71 (141) U/ml, Z=-2.041, P=0.041], the difference was statistically significant.(4)Distribution characteristics of comorbidities: There were 33 kinds of comorbidities in the 113 patients, and the proportion of COPD patients with comorbidities was 87.6%(n=99). The top three of the percentage of the comorbidities werecardiovascular system diseases (52.2%), allergic diseases (48.7%) and metabolic diseases (24.8%) separately.The incidence of malignant tumors in FE group was lower than that of in NFE group (11.7% vs 30.2%, χ2=5.955, P=0.015), the difference was statistically significant. Conclusions The patients in FE group of COPD have poor nutritional status and severe clinical symptoms, which may be associated with high BODE index, high value of total IgE and more severe impairment of lung function. Key words: Pulmonary disease, chronic obstructive; Acute exacerbation; Pulmonary function; Atopy; Comorbidity