Background Improving social circumstances (eg, an increase in income, finding a job or moving into a good neighbourhood) may reduce tobacco use, but robust evidence on the effects of such improvements is scarce. Accordingly we investigated the link between changing social circumstances and changing tobacco smoking using repeated measures data.

Methods 15 000 adults with at least two observations over three waves (each 2 years apart) of a panel study had data on smoking status, family, labour force, income and deprivation (both neighbourhood and individual). Fixed effects regression modelling was used.

Findings The odds of smoking increased 1.42-fold (95% CI 1.16 to 1.74) for a one log-unit increase in personal income among 15–24-year-olds, but there was no association of increased smoking with an increase in income among 25+ year olds. Moving out of a family nucleus, increasing neighbourhood deprivation (eg, 1.83-fold (95% CI 1.18 to 2.83) increased odds of smoking for moving from least to most deprived quintile of neighbourhoods), increasing personal deprivation and moving into employment were all associated with increased odds of smoking. The number of cigarettes smoked a day changed little with changing social circumstances.

Interpretation Worsening social circumstances over the short run are generally associated with higher smoking risk. However, there were counter examples: for instance, decreasing personal income among young people was associated with decreased odds of smoking, a finding consistent with income elasticity of demand (the less one's income, the less one can consume). This paper suggests that improving social circumstances is not always pro-health over the short run; a more nuanced approach to the social determinants of health is required.