Relationship of chronic obstructive pulmonary disease severity with early and late mortality in elderly patients with hip fracture

Introduction: We conducted a comparative study to compare patients with and without chronic obstructive pulmonary disease (COPD) and to analyze the effect of COPD severity on mortality in elderly patients with hip fractures who were diagnosed by pulmonologists. The purposes of this study were to compare early and late mortality after hip fracture between COPD and non-COPD patients and to assess risk factors of mortality after hip fractures in elderly patients with COPD. Methods: This study included 1294 patients (1294 hips) who were diagnosed as having unilateral femoral neck or intertrochanteric fractures and who underwent surgery at two hospitals between 2004 and 2017. The patients were categorized into a non-COPD group (853 patients) and a COPD group (441 patients; mild-to-moderate [354 patients] and severe-to-very severe COPD subgroups [87 patients] ). The cumulative crude mortality rate was calculated, and 30-day, 60-day, 3-month, 6-month, and 1-year mortality rates were compared between the non-COPD and COPD groups. Logistic regression analysis was conducted to identify independent factors associated with mortality. Results: The 30-day, 60-day, 3-month, 6-month, and 1-year postoperative cumulative mortality rates were 1.3%, 2.5%, 3.5%, 6.6%, and 10.7%, respectively, in the non-COPD group, and 2.9%, 5.7%, 7.7%, 11.8%, and 16.6%, respectively, in the COPD group (p = 0.049, p = 0.004, p = 0.002, p = 0.002, and p = 0.004, respectively). The 30-day, 60-day, 3-month, 6-month, and 1-year postoperative cumulative mortality rates in the severe-to-very severe COPD group were 4.6%, 6.9%, 11.5%, 20.7%, and 26.4%, respectively. In elderly patients with hip fracture, COPD increased the risk of mortality for 1.6 times and 1.7 times at 3 months and 1 year postoperative, respectively. In subgroup analysis, severe-to-very severe COPD was associated with 1.55-fold and 1.65-fold increased postoperative mortality risk at 6 months and 1 year respectively, as compared with mild-moderate COPD. Conclusions: In elderly patients with hip fracture, the comparison between the COPD and non-COPD patients revealed that COPD was an independent factor of mortality at a minimum of 1-year follow-up, and COPD severity in patients with hip fracture was also a risk factor of 6-month and 1-year mortality. (C) 2019 Elsevier Ltd. All rights reserved.