PDF(Pubmed)
Abstract：
BACKGROUND: Reducing cigarettes per day may lower the risk of lung cancer compared with continuing to smoke at the same intensity. Other changes in smoking behaviors, such as increasing cigarette consumption or quitting for a period and relapsing, may also affect lung cancer risk.
METHODS: We examined changes in smoking status and cigarettes per day among 24 613 Finnish male smokers aged 50-69 years who participated in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study. Longitudinal data on smoking were collected during study follow-up visits 3 times a year (approximately every 4 months) between 1985 and 1993. Incident lung cancer patients through 2012 were identified by the Finnish Cancer Registry. Risk ratios (RRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards regression.
RESULTS: Compared with smoking 20 cigarettes per day continuously across the intervention period, reducing an average of 5 cigarettes per day per year while smoking was associated with a 20% lower risk of lung cancer (95% CI = 0.71 to 0.90). A substantially lower risk of lung cancer was also observed when participants smoked at 50% (RR = 0.72, 95% CI = 0.57 to 0.90) and 10% (RR = 0.55, 95% CI = 0.36 to 0.83) of study visits, relative to smoked at 100% of study visits.
CONCLUSIONS: Smokers may lower their risk of lung cancer by reducing smoking intensity (cigarettes per day while smoking) and the time they smoke. However, quitting smoking completely is the most effective way for smokers to reduce their risk of lung cancer.
METHODS: We examined changes in smoking status and cigarettes per day among 24 613 Finnish male smokers aged 50-69 years who participated in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study. Longitudinal data on smoking were collected during study follow-up visits 3 times a year (approximately every 4 months) between 1985 and 1993. Incident lung cancer patients through 2012 were identified by the Finnish Cancer Registry. Risk ratios (RRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards regression.
RESULTS: Compared with smoking 20 cigarettes per day continuously across the intervention period, reducing an average of 5 cigarettes per day per year while smoking was associated with a 20% lower risk of lung cancer (95% CI = 0.71 to 0.90). A substantially lower risk of lung cancer was also observed when participants smoked at 50% (RR = 0.72, 95% CI = 0.57 to 0.90) and 10% (RR = 0.55, 95% CI = 0.36 to 0.83) of study visits, relative to smoked at 100% of study visits.
CONCLUSIONS: Smokers may lower their risk of lung cancer by reducing smoking intensity (cigarettes per day while smoking) and the time they smoke. However, quitting smoking completely is the most effective way for smokers to reduce their risk of lung cancer.
摘要：
背景：与继续以相同强度吸烟相比，每天减少吸烟可能会降低患肺癌的风险。吸烟行为的其他变化，例如增加香烟消费或戒烟一段时间并复发，也可能影响肺癌的风险。
方法：我们检查了24,613名50-69岁的芬兰男性吸烟者的吸烟状况和香烟/日的变化，β-胡萝卜素癌症预防（ATBC）研究。在1985年至1993年之间，每年三次（大约每4个月）的研究随访期间收集有关吸烟的纵向数据。芬兰癌症登记处确定了到2012年的肺癌发病率。使用Cox比例风险回归估计风险比（RR）和95％置信区间（95CI）。
结果：与整个干预期间每天连续吸烟20支香烟相比，每年平均减少5支香烟,同时吸烟与肺癌风险降低20%相关(95CI:0.71~0.90).当参与者在研究访视中吸烟50％（RR=0.72;95CI：0.57-0.90）和10％（RR=0.55;95CI：0.36-0.83）时，肺癌的风险也大大降低。相对于100%的研究访视时的吸烟。
结论：吸烟者可以通过减少吸烟强度（吸烟时每天吸烟）和吸烟时间来降低患肺癌的风险。然而,完全戒烟是吸烟者降低患肺癌风险的最有效方法。
方法：我们检查了24,613名50-69岁的芬兰男性吸烟者的吸烟状况和香烟/日的变化，β-胡萝卜素癌症预防（ATBC）研究。在1985年至1993年之间，每年三次（大约每4个月）的研究随访期间收集有关吸烟的纵向数据。芬兰癌症登记处确定了到2012年的肺癌发病率。使用Cox比例风险回归估计风险比（RR）和95％置信区间（95CI）。
结果：与整个干预期间每天连续吸烟20支香烟相比，每年平均减少5支香烟,同时吸烟与肺癌风险降低20%相关(95CI:0.71~0.90).当参与者在研究访视中吸烟50％（RR=0.72;95CI：0.57-0.90）和10％（RR=0.55;95CI：0.36-0.83）时，肺癌的风险也大大降低。相对于100%的研究访视时的吸烟。
结论：吸烟者可以通过减少吸烟强度（吸烟时每天吸烟）和吸烟时间来降低患肺癌的风险。然而,完全戒烟是吸烟者降低患肺癌风险的最有效方法。
