Contribution of time-varying measures of health behaviours to socioeconomic inequalities in mortality

A higher prevalence of unhealthy behaviours in lower socioeconomic groups contributes to socioeconomic inequalities in mortality.
Recent cohort studies suggest that the contribution of health behaviours to socioeconomic inequalities in mortality is larger when measured repeatedly over time (‘time-varying’) instead of once only (‘time-fixed’).
While explanations for the larger contribution of health behaviours have been mostly attributed to changing socioeconomic gradients in health behaviours over time, other mechanisms probably play a more prominent role. Several mechanisms can cause differences in results between models with time-varying and time-fixed mediators, perhaps most notably related to a change in the association between health behaviours and mortality.
Moreover, mechanisms can differ between risk factors. A systematic examination of the most likely mechanisms will help ascertain the causes that drive socioeconomic inequalities in mortality. http://jech.bmj.com/content/early/2016/07/11/jech-2016-207642.full