Study design: Retrospective longitudinal cohort.
Objectives: To determine if former smokers undergoing lumbar spine surgery have distinct baseline and postoperative patient-reported outcomes (PROs) compared with never smokers and current smokers.
Summary of background data: Smoking has known deleterious effects on patients undergoing lumbar spine surgery. However, former smokers have not been extensively evaluated. There are few studies regarding the relationship between pack-years or duration of smoking cessation, and subsequent clinical outcome.
Methods: Patients undergoing lumbar spine surgery at three Quality Outcomes Database participating sites were identified. Demographic, surgical and PRO data including pre-op and 12-month post-op back and leg pain scores, Oswestry Disability Index (ODI) and EuroQOL-5D were collected. Smoking status was assessed from individual medical records. Three cohorts, never smokers, former smokers and current smokers, were compared. Association between PROs and quantitative smoking history and duration of pre-op smoking cessation were evaluated in the former smokers.
Results: Of 1187 eligible cases, 843 (71%) had complete data, with 477 never, 250 former, and 116 current smokers. Among patients who had a fusion, baseline and 12-month post-op PROs were significantly different between cohorts, with former smokers having intermediate scores between current and never smokers. In the decompression only group, 12-month ODI was worse in the Current smokers, but overall the effects were much less pronounced. There was a significant negative correlation between smoke-free days before surgery and baseline back pain, ODI, 12-month leg pain and ODI and improvement in ODI. However, the correlation coefficients were small.
Conclusion: Former smokers have distinct baseline and 12-month post-op PROs that are intermediate between those of never smokers and current smokers. Smoking cessation does not entirely mitigate the negative effects of smoking on baseline and postoperative PROs for patients undergoing lumbar fusion surgery. This effect is less pronounced in patients undergoing decompression alone.
Level of evidence: 2.