Abstract
BACKGROUND: Cigarette smoking is a major contributor to disability and premature death worldwide. Given the impact of smoking on population health, it is important to understand trends and socio-demographic patterns that can be most informative to public health planning. The objectives of this study are to establish a time series of cigarette smoking in Belgium, forecast future smoking prevalence, and examine socio-demographic patterns in smoking. METHODS: Using six waves of the Belgian Health Interview Survey (1997-2018), we modelled smoking prevalence and forecast trends to 2040 with a Bayesian generalized linear model incorporating population projections by age, sex, region, and educational attainment to capture demographic shifts over time. RESULTS: Based on modelled estimates anchored on BHIS data from 1997 to 2018, smoking prevalence in Belgium declined from 29.6% (95% CI: 25.0-34.6%) in 1997 to 17.2% (95% CI: 12.5-23.5%) in 2025. Model projections indicate a further decrease to 12.9% (95% CI: 7.3-22.4%) by 2040. In 2025, men are estimated to smoke at about 1.4 times the rate of women-20.2% (95% CI: 14.9-27.6%) versus 14.2% (95% CI: 10.2-19.6%)-a gap expected to narrow but persist by 2040 (14.5%, 95% CI: 8.4-25.6% vs. 11.2%, 95% CI: 6.3-19.3%). Across regions, the steepest decline is projected in Flanders (from 28.5% to 11.4%), followed by Brussels-Capital (31.1% to 13.3%) and Wallonia (31.0% to 15.5%), which is expected to remain the highest. Socioeconomic inequalities also persist: by 2040, smoking prevalence is projected to range from 19.0% (95% CI: 12.2-36.2%) among those with lower secondary education to 7.5% (95% CI: 4.7-13.1%) among those with more than secondary education. CONCLUSIONS: Smoking prevalence in Belgium is declining and is projected to continue this downward trend. However, persistent inequalities by sex, educational attainment, and age may result in uneven health benefits across the population. Addressing these disparities through targeted tobacco control measures will be crucial to ensuring equitable health gains for all.