Modelling annual prevalence of tobacco consumption in Spain, 1991-2020

The aim of this study was to estimate the series of tobacco smoking prevalence year-by-year in Spain, by sex and age group, for the period 1991-2020. Based on smoking prevalence obtained from national surveys and smoking-related auxiliary information from public statistics, we fitted a multinomial logistic mixed model with random area and time effects. Joinpoint regression was used to identify changes in the prevalence series across the period. To analyse the precision of the model-based estimates, we calculated the coefficients of variation. Between 1991 and 2020, the prevalence of smoking in Spain decreased in both sexes. In the 15-24 age group, the prevalence of smokers showed no differences by sex until 2007, after which prevalence in men exceeded that of women. However, in women aged 55 and over prevalence of smoking has been rising since 1991. After applying the model, the precision of smoking prevalence estimates improved. The reconstruction of a detailed series of tobacco smoking prevalence provides insight into the evolution of the tobacco epidemic in Spain. A detailed analysis by sex and age shows different trends in the prevalence of smoking among women that should be considered when control measures are formulated.