OBJECTIVETo assess the value of neutrophil?to?lymphocyte ratio (NLR) for predicting type 2 diabetes mellitus (T2DM) in patients with chronic obstructive pulmonary disease (COPD).

METHODSA cohort of 404 non?diabetic patients diagnosed with stable COPD between January, 2010 and December, 2012 at Zhujiang Hospital were enrolled and followed up for 3 years, during which fast blood glucose (FBG) was monitored every 6 months. The primary endpoint was the occurrence of T2DM, and the cumulative incidence of T2DM in this cohort was calculated. The patients who developed T2DM and those without T2DM at the end of the follow?up were compared for clinical parameters to identify the potential predictors for T2DM in patients with stable COPD.

RESULTSAfter follow?up for a mean of 2.1 years, 41 (10.1%) patients with COPD developed T2DM, who showed significantly higher baseline NLR levels than those without T2DM (P<0.001). The receiver?operating characteristic (ROC) analysis revealed that the optimum cut?off value for NLR was 5.626. Spearman rank correlation analysis suggested that the incidence of T2DM in the patients was positively correlated with the number of hospital admissions for acute exacerbation of COPD in the past year (r=0.136, P=0.006), hypertension (r=0.151, P=0.002) and NLR (r=0.340, P<0.001). Logistic regression analysis identified triglyceride (TG) (P=0.047) and NLR (P<0.001) as the independent risk factors for T2DM in patients with COPD.

CONCLUSIONThe occurrence of T2DM in COPD patients is closely related to NLR level, which may serve as an early predictor for T2DM in these patients.