Fasting blood glucose levels and prognosis in patients with non-small-cell lung cancer: a prospective cohort study in China

Purpose: Non-small-cell lung cancer (NSCLC) is the most diagnosed lung cancer and is associated with poor prognosis. This study aimed to analyze whether fasting blood glucose (FBG) levels could provide prognostic information in Chinese patients with NSCLC, using the Suzhou Lung Cancer Survival study. Patients and methods: A prospective cohort study of adult patients with primary NSCLC was performed. The patients who were hospitalized between January 2016 and April 2018 in two hospitals affiliated with Soochow University were recruited. Patient information, including lifestyle habits and clinical and laboratory data, were collected through face-to-face interviews and evaluation of medical records. Follow-up was initiated from the date of patient enrollment until May 8, 2018 or until patient death. The long-term survival of patients was assessed every 6 months. Patient vital status was confirmed by using hospital records, telephone interview, or local death registration system. Cox proportional hazards regression was used to estimate hazard ratio and 95% confidence interval (CI) for death, with adjustment for cancer stage, medical treatments, smoking, and other potential confounders. Results: A total of 387 patients were included in the analysis, and the numbers (percentages) of patients with stages I, II, III, and IV NSCLC were 53 (13.7%), 41 (10.6%), 64 (16.5%), and 215 (55.6%), respectively. The median duration of follow-up was 19.1 months. Compared with patients in the second tertile of FBG, the HRs for mortality were 2.16 (95% CI: 1.26-3.73) and 1.87 (95% CI: 1.03-3.42) for those in the lowest one and diabetic group, respectively. Subgroup analysis according to various patient characteristics confirmed these associations. Conclusion: Diabetes and low FBG could be important predictors of death in patients with NSCLC. Maintaining appropriate blood glucose levels may improve prognosis in patients with NSCLC.