Tobacco Smoking Independently Predicts Lower Patient-Reported Outcomes: New Insights on a Forgotten Epidemic.

Background: Although smoking is a well-accepted risk factor for surgical complications, the effect of smoking on patient-reported outcomes (PROs) has not been previously investigated. Prompted by an increasingly value-conscious healthcare environment, the purpose of this study is to investigate the association between smoking and PROs in total joint arthroplasty (TJA).

Methods: A retrospective review of 713 primary total hip and knee replacements was performed. Two cohorts were compared: (1) current smokers and (2) previous/never smokers at the time of TJA. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and the Short Form-12 Physical Composite Summary (SF-12 PCS) and Short Form-12 Mental Composite Summary were assessed preoperatively and again at 6 and 12 months postoperatively. The primary outcomes were the net changes and absolute outcome scores at final follow-up. Postoperative patient satisfaction was also assessed as a secondary outcome. Linear mixed-effects regression analysis was performed.

Results: There were significant demographic and preoperative health disparities as measured by PROs among smokers. After adjusting for baseline differences, smokers achieved significantly lower improvements in WOMAC (P = .002) and SF-12 PCS (P = .03) compared to nonsmokers. For each unit increase in packs per day smoked, the WOMAC scores increased (worsened) by 7.7 points (P = .003) and SF-12 PCS decreased by 4.8 points (P = .001). At final follow up, nonsmokers had significantly better absolute scores for all outcomes (except for mental health) and were more likely to be satisfied with surgery (89% vs 82%, P = .052).

Conclusion: Tobacco smoking is an independent predictor for lower PROs after TJA and this relationship is dose-dependent. The negative impact of smoking does not appear to be related to impaired psychological health. As we transition to value-based care delivery models, this study provides further evidence that smoking cessation should be strongly recommended as a modifiable risk factor before embarking on elective TJA. Studies are still needed to define the optimal window for smoking cessation.