Association of Cumulative Socioeconomic and Health-Related Disadvantage With Disparities in Smoking Prevalence in the United States, 2008 to 2017.

Importance: Understanding emerging patterns of smoking disparities among disadvantaged populations can guide tobacco control policy. Objective: To estimate disparities in smoking prevalence associated with the number of socioeconomic and health-related disadvantages faced by a population among US adults from 2008 to 2017. Design, Setting, and Participants: Nationally representative cross-sectional annual household-based probability sample of US noninstitutionalized residents. Polytomous regression estimated associations of disadvantage variables, survey year, and their interaction with the following 3 pairwise contrasts: current vs never smoking (estimate of overall disparities), current vs former smoking (unique contribution of disparities in smoking cessation), and former vs never smoking (unique contribution of disparities in smoking initiation). The setting was in-home face-to-face interviews. Participants were respondents in 2008 to 2017 survey years who were aged 25 years or older (N = 279 559). Exposures: Self-reported past-year unemployment, income below the federal poverty line, absence of high school diploma, disability/limitation interfering with daily functions, serious psychological distress on the Kessler 6-item screen, and at least 60 past-year heavy drinking days, each coded yes or no. These indicators were summed in a cumulative disadvantage index (0, 1, 2, 3, 4, or 5 or 6). Main Outcomes and Measures: Self-reported current, former (ever smoked ≥100 cigarettes, had since quit, and not currently smoking), and never (<100 cigarettes) smoking.
Results: Among 278 048 respondents (mean [SD] age, 51.9 [16.8] years; 55.7% female) with data on smoking history (99.5% of the sample), the mean current smoking prevalence across 2008 to 2017 compared with populations without disadvantages was successively higher among populations with 1 disadvantage (21.4% vs 13.8%; current vs never smoking adjusted odds ratio [OR], 2.34; 95% CI, 2.27-2.43), 2 disadvantages (26.6% vs 13.8%; OR, 3.55; 95% CI, 3.39-3.72), 3 disadvantages (35.1% vs 13.8%; OR, 5.35; 95% CI, 5.05-5.66), 4 disadvantages (45.7% vs 13.8%; OR, 8.59; 95% CI, 7.91-9.34), or 5 or 6 disadvantages (58.2% vs 13.8%; OR, 14.70; 95% CI, 12.30-17.50). In current vs former and former vs never smoking status contrasts, ORs were lower but also showed successively greater associations with increasing cumulative disadvantage. Current (vs never) smoking odds significantly declined each year among populations with 0 (OR, 0.95; 95% CI, 0.94-0.96), 1 (OR, 0.96; 95% CI, 0.95-0.97), or 2 (OR, 0.98; 95% CI, 0.97-0.99) disadvantages but did not change across 2008 to 2017 among those with 3 or more disadvantages. Conclusions and Relevance: Results of this study demonstrate that US disparities in smoking prevalence from 2008 to 2017 were successively larger with each additional disadvantage faced, were expressed in higher smoking initiation odds and lower smoking cessation odds, and widened over time.