Trends in the Average Age of Quitting Among U.S. Adult Cigarette Smokers.

INTRODUCTION: Quitting smoking at any age confers health benefits. However, studies have suggested that quitting by age 35 years leads to mortality rates similar to never smokers. This study assessed whether the mean and median ages of past-year quitting and prevalence of past-year quit attempts and successful quitting by age group changed over time. METHODS: Data came from 113,599 adult cigarette smokers participating in the 1997-2012 National Health Interview Survey, an annual, cross-sectional household survey of U.S. adults aged ≥18 years. Mean and median ages of past-year successful abstinence (quit 6-12 months) were computed. Orthogonal polynomial logistic regression models tested for trends in quit attempts and successful quitting. Data were analyzed in 2014. RESULTS: The average age of quitting (40.0 years in 1997-1998, 39.5 years in 2011-2012, p=0.80) and median age of quitting (35.9 years in 1997-1998, 36.9 years in 2011-2012, p=0.62) did not change over time. During 1997-2012, the percentage of smokers making a past-year quit attempt increased among those aged 25-34, 35-44, and 45-64 years; the percentage of smokers who reported quitting successfully increased among those aged 25-34 and 35-44 years (p<0.001). CONCLUSIONS: Although the average age of quitting did not change over time, increases in past-year quit attempts and successful quitting occurred among adults aged 25-44 years. Proven population-level interventions--including price increases, mass media campaigns, comprehensive smoke-free policies, and health systems interventions--should be continued to further increase cessation, particularly among younger adults.