OBJECTIVE:To investigate the impact that chronic obstructive pulmonary disease (COPD) has on postoperative complication rates, ambulation, and hospital length of stay for elderly spinal deformity patients after elective spinal fusion (≥3 levels). METHODS:The medical records of 559 elderly (≥60 years old) spine deformity patients undergoing elective spinal fusion (≥3 levels) at a major academic institution from 2005 to 2015 were reviewed. We identified 60 patients with COPD (10.7%) and 499 patients without COPD (89.3%). Patient demographics, comorbidities, postoperative complications, ambulatory status, and readmission rates were collected. The primary outcomes investigated in this study were complication rates and length of hospital stay. RESULTS:Demographics and comorbidities were similar between groups, with a difference in proportion of smokers (COPD group: 25.0% vs. no COPD group: 9.6%, P = 0.0004). The median number of fusion levels (P = 0.840), operative time (P = 0.842), estimated blood loss (P = 0.336), and incidences of durotomy (P = 0.258) was similar between both cohorts. The COPD cohort experienced a higher rate of postoperative fever (10.0% vs. 3.0%, P = 0.007) and pneumonia (5.0% vs. 0.4%, P = 0.0004), respectively. There was a significant difference in the number of feet walked on the first day of ambulation after surgery (COPD group: 58.6 ± 78.4 vs. no COPD group: 84.0 ± 102.8, P = 0.040). Length of hospital stay was significantly longer in the COPD cohort than the no COPD cohort (7.7 ± 6.4 vs. 6.0 ± 4.0 days, respectively; P = 0.0498). CONCLUSIONS:Our study demonstrates that elderly patients with COPD have increased lengths of stay and higher rates of postoperative pneumonia after spinal fusion. This determination identifies a potentially modifiable risk factor for increased utilization of health care resources.