[Regional differences in adults' smoking pattern: findings from China Kadoorie Biobank study in 10 areas in China]

To describe the regional differences in adults' smoking pattern found by China Kadoorie Biobank (CKB) study involving half million adults in 10 areas in China.

After exclusion of the adults with self reported histories of coronary heart disease, stroke, cancer and chronic obstructive pulmonary disease at baseline survey, the area specific differences in smoking pattern of 452 829 subjects aged 30-79 years was analyzed.

The overall rate of current smoker was higher in males (64.2%) than in females (2.1%). For females, the current smoker rate was higher in Harbin (10.5%) and Sichuan (8.5%) than in other areas. For males, the current smoker rate and the average numbers of cigarettes smoked per day were high in Hunan (68.8%, 20.9) and Sichuan (67.2%, 21.5) ; the current smoker rate was lowest (49.9%) but the average number of cigarettes smoked per day was highest (21.9) in Haikou. On the other hand, Gansu showed the highest rate of current smoker (71.4% ) with a lower mean number of cigarettes smoked per day (14.9). Most current smokers in males (88.3% ) smoked filter cigarettes, while hand-rolled cigarettes were commonly used in Sichuan (38.8%) and Gansu (37.8%) and pipes or water pipe were mainly used in Henan (14.6%).

The rate of current smoker and other patterns of smoking including cigarette type, daily amount and inhalation depth varied greatly among the adults in 10 areas covered by CKB study.