How does rate of smoking cessation vary by age, gender and social grade? Findings from a population survey in England

Aims To assess the incidence of long-term smoking cessation as a function of age, gender, social grade and their interactions. Design and setting Cross-sectional surveys of population representative samples of smokers in England. Participants A total of 24 094 ever smokers (>= 21 and <= 60 years of age) participating in household surveys between November 2006 and February 2011. Measurements The ratio of long-term (>1 year) ex-smokers to ever-smokers was calculated for each age. Regression analyses were used to model the association between age and quit ratio, with the change in quit ratio by year of age n years versus all years up to n-1 years, yielding an estimate of the quitting incidence at that age. Analyses were conducted for the entire sample and then for the sample stratified by gender and social grade, and interactions assessed between these variables. Findings A cubic trend was needed to fit the data. The estimated quitting incidence between ages 21 and 30 was 1.5% (95% CI: 1.0%-2.0%), between 31 and 50 it was 0.3% (95% CI: 0.2%-0.5%) and between 51 and 60 it was 1.2% (95% CI: 0.7%-1.7%). Age interacted with gender and social grade: women and smokers from higher social grades had a higher incidence of quitting than men and those from lower social grades specifically in young adulthood. Conclusions The incidence of smoking cessation in England appears to be greater in young and old adults compared with those in middle age. Women and higher social grade smokers show a greater incidence of quitting than men and those from lower social grades specifically in young adulthood.