Smoking cessation between teenage years and adulthood

Most smokers begin smoking in adolescence. It is less well known how young people quit smoking and the factors that are associated with this process. A 15-year follow-up study on the North Karelia Youth Project has made it possible to assess these factors using a longitudinal study design. The project began in 1978 with students in Grade 7 of junior high school (age 13 years) and concluded in 1980 when the students reached Grade 9 (age 15 years). The follow-up study included four additional surveys. The present analyses are based on the data collected at ages 15, 21 and 28. The original sample comprised 903 students and the response rate of the last survey was 71%. A quarter (26%) of daily smokers and about half (46%) of occasional smokers at age of 15 had quit by the age of 28. The cessation rate was higher among females than males (P = 0.006). The cessation rate was higher among married (P = 0.015), employed (P = 0.01) and white-collar workers (P = 0.006). Cessation was less prevalent among those who had friends (P < 0.001) and family (P = 0.012) members who smoked. The cessation rate was lower among those who consumed fatty milk (P = 0.050), had less leisure-time physical activity (P = 0.032) and consumed more alcohol (P < 0.001). One-third of all teenage smokers stop smoking before the age of 28, averaging a 2.3% annual decline. Cessation is greater among occasional than daily smokers and greater overall among females.