Effects of smoking on serum levels of IL-6,IL-18,CC16,and nutritional status in stable chronic obstructive pulmonary disease patients

ZHONG Ping; FAN Xianming; JIANG Xuelian; HUANG Chengliang; XIONG Bin

doi:10.3969/j.issn.1002-266X.2017.25.008

Abstract：Objective To explore the effects of smoking on the serum levels of interleukin-6 (IL-6),IL-18,Clara cell secretory protein 16 (CC16),and nutritional status in stable chronic obstructive pulmonary disease (COPD)patients. Meth-ods Data of 200 patients (COPD group)and 100 healthy persons (control group)were collected,and the results of Mini Nutritional Assessment (MNA)were performed,the lung function for all subjects were tested. The serum levels of IL-6,IL-18,and CC16 in the two groups were detected by ELISA. According to the smoking history,smokers in the COPD group were selected as the COPD smoking subgroup,and the control group were divided into the normal smoking subgroup and nonsmok-ing subgroup. According to the smoking index (SI),the COPD smoking subgroup was further divided into SI <400 subgroup and SI ≥ 400 subgroup. Spearman correlation analysis was applied to analyze the correlations of SI and MNA with the serum levels of IL-6,IL-18,and CC16 in patients with stable phase of smoking COPD. Results There were no significant differ-ences in age,gender,and smoking index between the COPD group and the control group (all P >0. 05). Compared with thecontrol group,the forced expiratory volume in one second (FEV 1 )%,FEV 1 / forced vital capacity (FVC)%,serum CC16 level,and the MNA values were decreased and the serum IL-6 and IL-18 levels were increased significantly in the COPD group (all P <0. 01). Compared with the normal nonsmoking subgroup,the serum levels of IL-6 and IL-18 were increased significantly and the serum CC16 level was decreased in the COPD and the normal smoking subgroups. Compared with the normal smoking subgroup,the serum levels of IL-6 and IL-18 were increased significantly and the serum CC16 level was de-creased in the COPD smoking subgroup (all P <0. 05). Compared with the SI <400 subgroup,the serum levels of IL-6 and IL-18 were increased significantly and the serum CC16 level and the MNA values were decreased in the SI ≥ 400 subgroup (all P <0. 05). Correlation analysis showed that SI in patients with stable phase of smoking COPD was positively correlated with the serum levels of IL-6 and IL-18 (r =0. 443,0. 338;both P <0. 01),and negatively correlated with the serum CC16 level (r = -0. 423,P <0. 01). SI was negatively correlated with the MNA values (r = -0. 304,P <0. 05);the MNA val-ues were negatively correlated with the serum levels of IL-6 and IL-18 (r = -0. 485,-0. 291;both P <0. 05),but were not correlated with the serum CC16 level (r =0. 111,P =0. 289). Conclusions Smoking could increase the serum levels of IL-6 and IL-18 and decrease the serum CC16 level in stable COPD patients,and smoking could increase the risk of malnutrition in COPD patients which has a positive correlation with smoking capacity.