Effect of chronic obstructive pulmonary disease on mortality in patients with non-small cell lung cancer

Abstract

Objective To investigate whether chronic obstructive pulmonary disease (COPD) affects the mortality of patients with non-small cell lung cancer (NSCLC) and the clinical characteristics of COPD with NSCLC and the risk factors influencing survival. Methods The clinical data of 221 smokers diagnosed with NSCLC and their follow-up information were retrospectively analysed.Patients were divided into COPD group (n=111) and non-COPD group (n=110). The overall survival rate and clinical features of two groups were compared.Cox proportional hazards regression was used to analyze the prognostic risk factors. Results (1)Eight patients (7.2%) in the COPD group were aware of their own COPD disease.The body mass index in the COPD group was significantly lower than that in the non-COPD group (t=2.039, P=0.048). The smoking index of the COPD group was significantly higher than that of the non-COPD group (t=2.697, P=0.009). The forced expiratory volume in one second (FEV1) and FEV1%pred of the COPD group were significantly lower than those of the non-COPD group (t=3.782, 4.129, all P<0.05). (2)The COPD group had significantly more dyspnea symptoms than the non-COPD group (χ2=4.126, P=0.043). There was no significant difference in other clinical symptoms between the two groups.(3)The percentage of cases of COPD combined with other malignant tumour was significantly higher than that of non-COPD group (χ2=15.498, P=0.028). (4)There was no significant difference in the survival rate between the two groups (P=0.396). (5)COPD had no influence on the survival rate of patients with NSCLC.Age, body mass index, advanced stage (stages Ⅲ and Ⅳ), and squamous cell carcinoma, Eastern Cooperative Oncology Group score ≥2, weight loss, and interstitial lung disease were independent risk factors for poor prognosis of NSCLC. Conclusions COPD is a potential disease co-existing with NSCLC.There are no differences in clinical symptoms of NSCLC patients with or without COPD-based disease except dyspnea.COPD-based disease does not affect the overall mortality of NSCLC patients. Key words: Carcinoma, non-small cell lung; Pulmonary disease, chronic obstructive; Mortality