D'Avanzo B, La Vecchia C, Negri E
Istituto di Ricerche Farmacologiche Mario Negri, Università di Milano, Italy.
Ann Epidemiol. 1994 Nov;4(6):455-9. doi: 10.1016/1047-2797(94)90005-1.
A cross-sectional analysis of a sample of 3235 males and 2513 females included in a structured framework of case-control studies of various neoplasms conducted in northern Italy assessed the relationship between age at starting smoking and amount of cigarettes smoked per day. Age-standardized proportions of light, moderate, and heavy smokers and mean numbers of cigarettes smoked per day according to age at starting, together with age- and sex-adjusted odds ratios of being a heavy smoker were computed. Age at starting smoking was strongly associated with the number of cigarettes smoked per day. This relationship was evident in men and women and at younger and elderly ages, although in women the mean numbers of cigarettes smoked was lower than in men, and age at starting was a stronger predictor of subsequent heavy smoking in people younger than 55 years than in the elderly. Among males who had started smoking before age 17, 64% smoked less than 25 cigarettes/d and 37% smoked 25 or more cigarettes; corresponding proportions were 73% and 27% among those who had started at age 30 or later. Age-standardized mean number of cigarettes smoked per day by men who started before age 17 was 23.5, compared to 20.0 for those who started at age 30 or later. Corresponding values for women were 16.8 and 10.5. Compared to those who started smoking at age 30 or later, the odds ratios of smoking more than 25 cigarettes/d for those who started before age 17 were 2.2 (95% confidence interval (CI), 1.6 to 3.0) for men and 5.4 (95% CI, 3.0 to 9.6) for women.(ABSTRACT TRUNCATED AT 250 WORDS)
对意大利北部开展的各种肿瘤病例对照研究结构化框架中纳入的3235名男性和2513名女性样本进行的横断面分析，评估了开始吸烟的年龄与每日吸烟量之间的关系。计算了按开始吸烟年龄划分的轻度、中度和重度吸烟者的年龄标准化比例以及每日平均吸烟量，同时计算了经年龄和性别调整的成为重度吸烟者的比值比。开始吸烟的年龄与每日吸烟量密切相关。这种关系在男性和女性中以及在年轻人和老年人中都很明显，尽管女性的平均吸烟量低于男性，并且开始吸烟的年龄在55岁以下人群中比在老年人中更能预测随后的重度吸烟情况。在17岁之前开始吸烟的男性中，64%每天吸烟少于25支，37%每天吸烟25支或更多；在30岁及以后开始吸烟的男性中，相应比例分别为73%和27%。17岁之前开始吸烟的男性年龄标准化每日平均吸烟量为23.5支，而30岁及以后开始吸烟的男性为20.0支。女性的相应数值分别为16.8支和10.5支。与30岁及以后开始吸烟的人相比，17岁之前开始吸烟的男性每天吸烟超过25支的比值比为2.2（95%置信区间(CI)，1.6至3.0），女性为5.4（95%CI，3.0至9.6）。（摘要截短为250字）
