Is smoking increasing social injustice in low or middle income nations? Smoke load/mortality rate associations across socioeconomic mortality disparities in Lithuania, Poland, Estonia, and Hungary

Background: Smoking is increasing in low and middle income nations. Smoking is both decreasing yet still the dominant cause of socioeconomic (SES) mortality disparities in high income nations. Possible contributions of smoking to SES mortality disparities in low or middle income nations have not been well quantified. So I studied cumulative tobacco smoke damage (smoke load)/mortality rate associations across socioeconomic strata in 1990 and 2000 in middle income nations Lithuania and Poland and their high income neighbors, Estonia and Hungary.

Methods: Published age adjusted mortality rates (rates) by SES were used. Lung cancer rates were used as a smoke load proxy since smoking status is a poor proxy for smoke load, overlooking smoking years, depth, sensitivity, age, and other aspects of smoke load. Lung cancer/other mortality rate regressions were run.

Results: Lung cancer rates were tightly (about R2=1, p< 0.1) associated with rates for all other mortality across socioecomic strata among males in each nation and year studied though the slopes of the associations, amounts of disparity, and overall mortality in less educated groups increased dramatically in Estonia and Lithuania but not Poland and Hungary from 1990 to 2000.

Discussion. The tight smoke load/mortality rate associations seen in diverse years and nations are consistent with prior findings that smoking can account for the great majority of socioeconomic mortality rate disparities in Scottish men. Smoke load increases in most strata in Lithuania and Estonia and decreases in Poland may account for the disparate mortality rates, disparities, and trends seen.