Patterns of adult cigarette smoking
When do adults start smoking, stop smoking, and increase or decrease smoking cigarettes? Are there groups of smokers with distinct trajectories across adulthood? Interventions could be timed and targeted based on such information.
Yvonne Terry-McElrath and YSI colleagues recently explored such patterns and found 12 distinct classes or patterns of smoking trajectories from age 18 to 50.
Three of the classes were characterized by no change over time:
-No smoking at any age (this applied to just over half of the respondents);
-Smoking less than a pack a day consistently across the years (about 5% of respondents);
-Smoking a pack or more a day over the years (7%).
Three classes showed increased smoking across age:
-From no smoking to less than a pack a day (about 3%);
-From no smoking to a pack+ per day (3%);
-From smoking less than a pack to a pack+ per day (3%).
Four classes included quitting:
-Quitting by age 23 after smoking less than a pack a day (about 8%);
-Quitting by age 35 after smoking less than a pack a day (5%);
-Quitting by age 35 after smoking a pack+ per day (3%);
-Quitting by age 40 after smoking a pack+ per day (4%).
Finally, two classes were characterized by several shifts in smoking:
-From no smoking to smoking less than a pack a day and back to no smoking (about 4%);
-From smoking less than a pack a day to no smoking and back to smoking less than a pack a day (4%).
The study was based on 15,247 participants in the Monitoring the Future study who responded to a baseline survey in 12th grade (from 1976 to 1982) and at least one follow-up survey by age 50. At each follow-up (ages 19/20, 21/22, 23/24, 25/26, 27/28, 29/30, 35, 40, 45, and 50) respondents were asked how frequently they smoked in the last 30 days; their answers were categorized into no smoking at all, less than a pack a day, and a pack or more a day.
Next week’s blog will cover gender differences in this study and ages at which shifts in smoking tend to happen.
Discontinuous Patterns of Cigarette Smoking from Age 18 to 50 in the U.S.: A Repeated-Measures Latent Class Analysis was published online in Nicotine & Alcohol Research in March, 2017. The study was funded by the National Institute on Drug Abuse.