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).

CONCLUSIONS

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.