Johnsen Marianne Bakke, Hellevik Alf Inge, Småstuen Milada Cvancarova, Langhammer Arnulf, Furnes Ove, Flugsrud Gunnar Birkeland, Nordsletten Lars, Zwart John Anker, Storheim Kjersti
Research and Communication Unit for Musculoskeletal Health, Oslo University Hospital, Oslo, Norway.
Faculty of Medicine, University of Oslo, Oslo, Norway.
PLoS One. 2017 Dec 28;12(12):e0190288. doi: 10.1371/journal.pone.0190288. eCollection 2017.
To investigate the total effect of smoking on total hip or knee replacement (THR/TKR) due to primary osteoarthritis (OA) and to quantify the indirect effect of smoking through body mass index (BMI). Participants from the Nord-Trøndelag Health Study (the HUNT Study) were linked to the Norwegian Arthroplasty Register to detect the first THR or TKR due to primary OA. A mediation analysis was used to decompose the total effect of smoking into a direct and indirect effect. BMI was considered a mediator in the analysis. All effects were estimated as hazard ratios (HRs) with 95% confidence intervals (CIs). The indirect effect of smoking mediated through BMI was expressed as a percentage (proportion*100). In total 55 188 participants were followed up during 17.2 years (median). We identified 1322 THRs and 754 TKRs. For men, the total effect of current vs. never smoking revealed a decreased risk of THR (HR 0.59, 95% CI 0.46-0.76) and TKR (HR 0.47, 95% CI 0.32-0.66). For women, current smoking increased the risk of THR (HR 1.34, 95% CI 1.11-1.60). For men, 6% and 7% of the risk reduction for THR and TKR, respectively, was mediated by BMI. We found a negative association between smoking and THR or TKR for men. On the contrary, smoking was associated with increased risk of THR for women. Most of the effect of smoking on joint replacement risk remained unexplained by BMI.
为了研究吸烟对原发性骨关节炎（OA）所致全髋关节或膝关节置换术（THR/TKR）的总体影响，并量化吸烟通过体重指数（BMI）产生的间接影响。来自北特伦德拉格健康研究（HUNT研究）的参与者与挪威关节成形术登记处进行关联，以检测首次因原发性OA进行的THR或TKR。采用中介分析将吸烟的总体影响分解为直接影响和间接影响。在分析中，BMI被视为中介变量。所有影响均以风险比（HRs）及95%置信区间（CIs）进行估计。吸烟通过BMI介导的间接影响以百分比（比例*100）表示。在17.2年（中位数）期间，总共对55188名参与者进行了随访。我们确定了1322例全髋关节置换术和754例全膝关节置换术。对于男性，当前吸烟者与从不吸烟者相比，全髋关节置换术风险降低（HR 0.59，95% CI 0.46 - 0.76），全膝关节置换术风险降低（HR 0.47，95% CI 0.32 - 0.66）。对于女性，当前吸烟会增加全髋关节置换术风险（HR 1.34，95% CI 1.11 - 1.60）。对于男性，BMI分别介导了全髋关节置换术和全膝关节置换术风险降低的6%和7%。我们发现男性吸烟与全髋关节置换术或全膝关节置换术之间存在负相关。相反，女性吸烟与全髋关节置换术风险增加有关。吸烟对关节置换风险的大部分影响仍无法用BMI解释。
