Wald N J, Idle M, Boreham J, Bailey A
Br Med J (Clin Res Ed). 1983 Oct 29;287(6401):1273-5. doi: 10.1136/bmj.287.6401.1273.
An objective index of inhaling cigarette smoke based on carboxyhaemoglobin concentrations and the carbon monoxide yields of cigarettes was used to investigate possible systematic differences in the extent of inhaling among light and heavy smokers when classified according to their self described inhaling habits. A total of 2108 men who smoked cigarettes were studied. Heavy smokers (20 or more cigarettes a day) had a higher average inhaling index than light smokers (fewer than 20 cigarettes a day) both among those who said that they inhaled and among those who said that they did not. This observation, together with indirect evidence that heavy smokers who inhale deeply may to some extent avoid depositing smoke condensate on their main bronchial epithelium, explains a hitherto unresolved anomaly--namely, that the risk of lung cancer is less among heavy cigarette smokers who say that they inhale than it is among those who say that they do not inhale.
基于羧基血红蛋白浓度和香烟一氧化碳产量的吸入香烟烟雾客观指标，被用于研究根据自我描述的吸入习惯分类的轻度和重度吸烟者在吸入程度上可能存在的系统差异。共研究了2108名吸烟男性。在表示吸入的人群以及表示不吸入的人群中，重度吸烟者（每天吸20支或更多香烟）的平均吸入指数均高于轻度吸烟者（每天吸少于20支香烟）。这一观察结果，连同重度吸烟者深吸气在一定程度上可能避免烟雾冷凝物沉积在其主支气管上皮的间接证据，解释了一个迄今未解决的异常现象，即声称吸入的重度吸烟者患肺癌的风险低于声称不吸入的重度吸烟者。
