Nicotine dependence in the United States: prevalence, trends, and smoking persistence.

BACKGROUND The prevalence of smoking in the United States has been closely monitored. However, little is known about the epidemiology of nicotine dependence. We studied DSM-III-R nicotine dependence in the United States, trends across cohorts, and the role of nicotine dependence in smoking persistence. METHODS The Tobacco Supplement to the National Comorbidity Survey was administered to a representative subset of 4414 persons aged 15 to 54 years. The World Health Organization's Composite International Diagnostic Interview was used to assess nicotine dependence. RESULTS Lifetime prevalence of nicotine dependence was 24%, nearly half of those who had ever smoked daily for a month or more. The highest risk for nicotine dependence occurred in the first 16 years after daily smoking began, at which point the rate declined and continued at a slower pace for several years. Nicotine dependence increased the risk of smoking persistence, with an odds ratio (OR) of 2.2 (95% confidence interval [CI], 1.6-3.0). Members of the most recent cohort, who were 15 to 24 years of age at the time of the survey, were the least likely to smoke daily, but those who smoked had the highest risk of dependence: OR for daily smoking in the most recent vs earliest cohort was 0.7 (95% CI, 0.5-0.9), and for dependence among smokers, 7.2 (95% CI, 5.0-10.4). CONCLUSIONS Despite evidence that nicotine dependence is the leading preventable cause of death and morbidity, it remains a common psychiatric disorder. Smoking cessation and the decline in uptake in recent years varied across subgroups of the population.