Does smoking have any effect on urinary stone composition and the distribution of trace elements in urine and stones

The role of particular elements in lithogenesis is still unclear and debated. Probably some of them may promote or conversely inhibit crystal nucleation of organic or mineral species. A few epidemiological data link smoking with the risk of calcium stones. The aim of this hospital-based study was to evaluate the distribution of trace elements in urine and urinary stones, and possible correlation with stone constituents in smoking and non-smoking individuals. 209 stones and urine samples collected from idiopathic stone-formers were analyzed to evaluate the mineral composition and the distribution of elements, 29 in stones and 21 in urine. Values were statistically compared considering smoking, arterial hypertension and coronary heart disease as grouping variables. No differences were noted either for comparison of mineral components or the elements concentrations in stones in both groups. The concentration of mercury in urine was higher in smokers than in non-smokers, but the statistical significance was at the moderate level. Our findings do not support the concept of possible association between smoking and urinary lithogenesis, but we believe that further investigations are needed in this area.