Risk factors of lung cancer complicated with symptomatic venous thromboembolism

Objective To seek risk factors of VTE in patients with lung cancer through analysis of clinical features of patients with lung cancer complicated with venous thromboembolism (VTE). Methods Retrospective investigation was performed on patients diagnosed with lung cancer and with complete clinical data who were hospitalized in Peking University People's Hospital from January 1, 2010 to December 31, 2014. According to the presence of symptomatic VTE, patients were distributed into two groups, VTE group and control group. Patients' clinical data and laboratory parameters were collected. Single factor analysis was applied to compare the differences between the two groups. t test or nonparametric test was applied for intragroup comparison of measurement data, and chi-square test was applied for the comparison of counting information. Logistic regression analysis was applied to explore risk factors of venous thromboembolism. For VTE patients with this diagnosis when they were hospitalized, D-dimer and PT were obtained after the occurrence of VTE, so D-dimer and PT were eliminated in the multiple factors analysis. SPSS 13.0 statistical software was applied for statistical management and analysis. Results 548 patients with lung cancer were include in the investigation, with male 357, female 191, average age of (63.8±10.9) years old, 46 patients in VTE group and 502 patinets in control group. According to the results of single factor analysis in gender, age, tumor pathologic type, tumor stage, WBC, Hb, PLT, CEA, ALT, FIB, D-dimer, PT, APTT, PT-INR, the tumor stage (χ2=14.177), CEA (t=2.129) and Hb (t=-2.424) were risk factors for lung cancer patients complicated with venous thromboembolism. Logistic regression analysis showed that tumor stage was the independent risk factor of lung cancer complicated with venous thromboembolism (OR 2.058, 95%CI 1.307-3.238, P=0.002) , and CEA (r=0.395, P<0.001) and Hb (r=-0.144, P=0.001) were associated with lung cancer stage. The area under the curve formed by D-dimer predicting VTE was 0.825 (95%CI 0.751-0.900, P<0.001). Conclusion Tumor stage is the only risk factor for lung cancer patients complicated with venous thromboembolism in the study. However, because this study is a retrospective study, other potential high risk factors causing VTE cannot be excluded. Key words: Lung neoplasms; Venous thromboembolism; Risk factor