AUGMENTATION OF SMOKING CESSATION EDUCATION BY URINARY COTININE MEASUREMENT

Monitoring the current smoking status by an. objective method may augm ent the effects of smoking cessation instruction. To quantitatively ev aluate smoking status and its modification by smoking cessation instru ction, urinary cotinine, a major metabolite of nicotine, was measured by radioimmunoassay in 64 patients with a smoking habit before and dur ing smoking cessation instruction. Urinary cotinine levels were used t o discriminate between smokers and nonsmokers (with 50 ng/ml used as a threshold). In 49 patients who claimed to have stopped smoking, urina ry cotinine concentrations 1 month after instruction indicated that on ly 30 (61%) of them had actually stopped (before: 243+/-104, after: 1/-3 ng/ml) (mean+/-standard deviation). In the remaining 15 patients w ho failed to stop smoking while reporting a reduction of cigarette con sumption (before: 27+/-12, after: 7+/-5/day), there was no appreciable reduction in urinary cotinine levels (before: 298+/-140, after: 229+/ -171 ng/ml). When the patients who had failed to stop smoking again re ceived intensive smoking cessation instruction, the success rate incre ased from 47% (30/64) to 69% (44/64) (p<0.05). Thus, urinary cotinine measurement may provide a useful and quantitative method for monitorin g actual smoking habits and thus augment the efficacy of smoking cessa tion educational programs.