National trends in frequency and amount of nondaily smoking, and relation to quit attempts, 2000-2012

Abstract

Introduction: To understand changes occurring in nondaily smoking, we assessed differences in demographics and trends in nondaily smoking, by smoking frequency and amount. Methods: Participants were 13 966 adult nondaily cigarette smokers (NDS) age 18 years and older responding to the 2000-2012 US National Health Interview Survey, an annual, nationally-representative, cross-sectional, household interview survey. We created a nine-level smoking frequency- amount variable using tertile cut points from the number of days smoked in the past 30 (1-7, 8-14, 15-29 days) and number of cigarettes smoked per day (cpd; 1-2, 3-5, ≥6). We computed weighted frequencies by low-, moderate-, high-frequency use, by low-, moderate-, high-cpd amount, and by demographics. We estimated temporal trends using weighted least squares regression, and the association between groups and past-year quit attempts using logistic regression. Results: Overall prevalence of nondaily smoking among adults remained stable between 2000 to 2012 (P = .62). The most prevalent nondaily smoking frequency-amount groups were: smoking 15-29 days (in the past 30), 3-5 cpd (20.2%); 1-7 days, 1-2 cpd (19.7%); 15-29 days, 1-2 cpd (14.9%); and 15-29 days, ≥6 cpd (12.1%). From 2000 to 2012, low-cpd NDS (1-2 cpd) across moderate (8-14 days) and high (15-29 days) frequency groups increased (P < .01), while moderate frequency-moderate cpd (8-14 days, 3-5 cpd; P < .05) and high frequency-high cpd (15-29 days, ≥6 cpd; P