Objective To investigate the relationships of the monocyte to high-density lipoprotein cholesterol ratio (MHR), the neutrophils to lymphocytes ratio (NLR) and the red blood cell distribution width (RDW) with atrial fibrillation (AF) in elderly patients with severe chronic obstructive pulmonary disease (COPD).

Methods A total of 143 patients with severe COPD in stable phase were selected, and according to incidence and classification of non-valvular AFparoxysmal AF (PAF), persistent and long-standing persistent and sustained AF (SAF), they were divided into COPD group (n=50), COPD combined with PAF group (n=45), and COPD combined with SAF group (n=48). Levels of MHR, NLR and RDW in peripheral blood were detected in the three groups. A binary Logistic regression model was used to analyze whether MHR, NLR and RDW were independent predictors of PAF and SAF. Receiver operating characteristic (ROC) curve was used to analyze the diagnostic efficacy of independent predictors.

Results MHR (OR=1.438; 95%CI, 1.107 to 2.962, P=0.029) and NLR (OR=2.715; 95%CI, 1.066 to 8.537, P=0.042) were the independent predictors of PAF in elderly patients with severe COPD. MHR (OR=1.477; 95%CI, 1.091 to 2.951, P=0.031), NLR (OR=2.628; 95%CI, 1.017 to 7.063, P=0.036) and RDW (OR=1.149; 95%CI, 1.003 to 4.655, P=0.047) were the independent predictors of SAF in elderly patients with severe COPD. ROC curve analysis showed that MHRarea under the curve (AUC) was 0.644, 95%CI, 0.556 to 0.831, Youden index was 0.653, sensitivity was 73%, and specificity was 80%and NLR (AUC was 0.732, 95%CI, 0.575 to 0.829, Youden index was 0.791, sensitivity was 78%, and specificity was 88%) had high diagnostic efficacies in predicting PAF in elderly patients with severe COPD, and the diagnostic efficiency reached the best value when NLR was combined with MHR for prediction (AUC was 0.803, 95%CI, 0.619 to 0.897). ROC curve analysis showed that MHR (AUC was 0.693, 95%CI, 0.519 to 0.766, Youden index was 0.753, sensitivity was 83%, and specificity was 92%), NLR (AUC was 0.736, 95%CI, 0.549 to 0.822, Youden index was 0.651, sensitivity was 91%, and specificity was 87%) and RDW (AUC was 0.708, 95%CI, 0.642 to 0.873, Youden index was 0.738, sensitivity was 94%, and specificity was 80%) had high diagnostic efficacies in predicting SAF in elderly patients with severe COPD, and the diagnostic efficiency reached the best value when NLR was combined with MHR and RDW for prediction (AUC was 0.824, 95%CI, 0.738 to 0.916).

Conclusion The combined detection of MHR, NLR and RDW in peripheral blood has important clinical value in predicting the occurrence and severity of AF in elderly patients with severe COPD.