Abstract
RATIONALE: The Food and Drug Administration is considering severely restricting the nicotine in cigarettes, to reduce smoking. A study showed that non-daily, intermittent smokers (ITS) randomized to very-low-nicotine-content cigarettes (VLNCCs) reduced their cigarette consumption. OBJECTIVES: To assess whether increased smoking intensity of VLNCCs compensated for some of the reduced cigarette consumption. METHODS: After a 2-week baseline smoking their own-brand cigarettes, 118 ITS were randomized to VLNCCs (~ 1 mg nicotine/g tobacco), and 120 to normal-nicotine-content cigarettes (NNCCs; ~ 16 mg/g) for 10 weeks. Laboratory measures of smoking intensity-total puff volume and carbon monoxide (CO) boost-assessed single cigarettes smoked in up to three laboratory topography sessions. Field measures assessed returned cigarette butts, averaged over up to five 2-week intervals: the mass of tobacco burned (computed from residual mass of butts) and the intensity of smoking (by scanning of returned filters). Analysis was by mixed model random effects models using baseline values as covariates. RESULTS: ITS in the VLNCC group puffed less smoke in topography sessions (-38.50 mL [-75.21, -1.78]; p < 0.04), but showed no difference in CO boost. Participants in the VLNCC group burned 0.02 [0.04, 0.002] grams less tobacco per cigarette (p < 0.03). Analysis of filters showed their smoking intensity declined over time, compared to NNCC participants (p < 0.04). "Cheating" by smoking normal cigarettes did not moderate these effects. CONCLUSIONS: ITS did not increase their smoking intensity when switched to VLNCCs; indeed, their smoking intensity decreased. Reductions in cigarette consumption seen when ITS are switched to VLNCCs were not compensated by increased smoking intensity.