Health Services Research and Development (HSR&D) Northwest Center of Excellence, Department of Veterans Affairs Puget Sound Health Care System, Seattle, WA 98101, USA.
Respir Med. 2012 Jul;106(7):1055-62. doi: 10.1016/j.rmed.2012.03.018. Epub 2012 Apr 25.
Smoking increases the risk of hospitalization for pneumonia, yet it is unknown if smoking cessation changes this risk. We sought to determine if smoking cessation and the duration of abstinence from tobacco reduce the risk of pneumonia hospitalization.
We performed secondary analysis of data collected from male United States Veterans participating in a randomized trial. We used Cox proportional-hazard models to estimate risk of hospitalization for pneumonia within one year of enrollment. We adjusted for confounders, including: demographics, comorbidity, alcohol use, prior pneumonia, inhaled corticosteroid use, and intensity of tobacco exposure. Among a restricted cohort excluding never smokers, we assessed for effect modification by a diagnosis of chronic obstructive pulmonary disease (COPD).
Of the 25,235 participants, we identified 6720 current, 13,625 former, and 4890 never smokers. Compared to current smokers, never smokers had a decreased (adjusted HR 0.48, 95% CI 0.31-0.74), while former smokers had no difference in (adjusted HR 0.83, 95% CI 0.63-1.09) risk of hospitalization for pneumonia. Among participants without COPD, former smokers had a lower risk of hospitalization (adjusted HR 0.65, 95% CI 0.45-0.95). However, this lower risk was isolated to those who quit tobacco more than 10 years previously (adjusted HR 0.62, 95% CI 0.41-0.93). Among those with COPD, there was no difference in risk with smoking cessation or duration of remaining tobacco-free.
Tobacco cessation is likely important in reducing hospital admissions for pneumonia, but its benefit depends on duration of smoking cessation and is likely attenuated in the presence of COPD.
吸烟会增加肺炎住院的风险，但目前尚不清楚戒烟是否会改变这种风险。我们旨在确定戒烟和戒烟时间是否会降低肺炎住院的风险。
我们对参与随机试验的美国男性退伍军人的数据进行了二次分析。我们使用 Cox 比例风险模型来估计一年内肺炎住院的风险。我们调整了混杂因素，包括：人口统计学、合并症、饮酒、既往肺炎、吸入皮质类固醇的使用以及烟草暴露的强度。在排除从不吸烟者的受限队列中，我们评估了慢性阻塞性肺疾病（COPD）诊断的效应修饰作用。
在 25235 名参与者中，我们确定了 6720 名当前吸烟者、13625 名以前吸烟者和 4890 名从不吸烟者。与当前吸烟者相比，从不吸烟者的风险降低（调整后的 HR 0.48，95%CI 0.31-0.74），而以前吸烟者的肺炎住院风险没有差异（调整后的 HR 0.83，95%CI 0.63-1.09）。在没有 COPD 的参与者中，以前吸烟者的住院风险较低（调整后的 HR 0.65，95%CI 0.45-0.95）。然而，这种较低的风险仅存在于那些戒烟 10 年以上的人群中（调整后的 HR 0.62，95%CI 0.41-0.93）。在 COPD 患者中，戒烟或持续不吸烟的时间对风险没有影响。
戒烟可能对降低肺炎住院的风险很重要，但戒烟的益处取决于戒烟的时间，并且在 COPD 存在的情况下可能会减弱。
