The California Tobacco Control Program's effect on adult smokers: (1) Smoking cessation

Objectives

To estimate national population trends in long‐term smoking cessation by age group and to compare cessation rates in California (CA) with those of two comparison groups of states.

Setting

Retrospective smoking history of a population sample from the US: from CA, with a comprehensive tobacco‐control programme since 1989 with the goal of denormalising tobacco use; from New York and New Jersey (NY & NJ), with similar high cigarette prices but no comprehensive programme; and from the tobacco‐growing states (TGS), with low cigarette prices, no tobacco‐control programme and social norms relatively supportive of tobacco use.

Participants

Respondents to the Current Population Survey–Tobacco Use Supplements (1992–2002; n?=?57?918 non‐Hispanic white ever‐smokers).

Main outcome measures

The proportion of recent ever‐smokers attaining long‐term abstinence (quit ?1?year) and the successful‐quit ratio (the proportion of all ever‐smokers abstinent ?1?year).

Results

Nationally, long‐term cessation rates increased by 25% from the 1980s to the 1990s, averaging 3.4% per year in the 1990s. Cessation increased for all age groups, and by >40% (p<0.001) among smokers aged 20–34?years. For smokers aged <50?years, higher cigarette prices were associated with higher quitting rates. For smokers aged <35?years, quitting rates in CA were higher than in either comparison group (p<0.05). Half of the ever‐smokers had quit smoking by age 44?years in CA, 47?years in NY & NJ, and by age 54 years in TGS.

Conclusion

Successful smoking cessation increased by 25% during the1990s in the US. Comprehensive tobacco‐control programmes were associated with greater cessation success than were with high cigarette prices alone, although both effects were limited to younger adults.There is considerable evidence that cigarette smoking will cause the premature death of approximately half of those who start and continue to smoke, with half of these deaths occurring before age 70?years.^1,2 Public health efforts to rapidly reduce the estimated 438?000 smoking‐related deaths in the US each year have targeted increasing successful quitting among current smokers.^1,3 The British Doctors Study² evaluated the relationship between age of smoking cessation and later mortality. The study suggests that smokers who quit successfully by age 35?years may avoid much of the excess mortality risk from smoking, those who quit successfully by age 50?years will avoid approximately half of the excess mortality risk accrued by continuing smokers and those who quit by age 60?years will avoid about one‐third of the excess mortality risk. These ages are useful cut‐points to assess progress towards tobacco‐control goals in population groups.There are several reasons to expect that successful cessation rates may have increased in the US during the 1990s. Many health economists feel that price increases are among the most effective policy approaches to reduce smoking behaviour.⁴ Significant increases in cigarette prices have consistently been associated with reductions in both per capita cigarette usage and smoking prevalence, with the latter presumed to occur largely through increased quitting.⁵ Real cigarette prices increased nationally in the US during the 1980s and 1990s, with the largest increase imposed by the tobacco industry in 1999, associated with the consolidated settlement in 1998 of lawsuits brought by attorneys general from 46 states.⁶ In addition, during the 1990s, many individual states increased their excise taxes on tobacco products.⁷ These high prices may have encouraged more smokers both to try to quit and to successfully maintain cessation. Thus, quitting indices should have increased across the US, with more marked increases seen in states with higher cigarette prices.In addition, during the 1990s, nicotine replacement products such as the nicotine patch and nicotine gum became widely available, following randomised trials that showed their efficacy.⁸ Older smokers and those who smoked more heavily were more likely to use these cessation aids; by 2001, approximately 40% of smokers aged >35?years had used nicotine replacement products to assist in quitting, leading to an expectation that the major increase in successful quitting would occur in older smokers.⁹During the 1990s, there were marked differences among US states in initiatives targeting tobacco cessation. Thus, it is of interest to assess changes in quitting rates not only for the US as a whole but also among groups of states that differed in their tobacco‐control initiatives. Among US states, California (CA) was the first to begin a comprehensive tobacco control programme in 1989, which had one specific programme goal to encourage smoking cessation and a broader mandate to change community norms regarding tobacco use.^10,11 Through the 1990s, CA was unique in spending an average of $3.67 per person per year on a comprehensive public health programme to change smoking‐related norms.¹² The programme included price increases and other interventions, and a mass media campaign in which about one‐quarter of the advertisements encouraged smokers to quit.¹³ There is considerable evidence that such a mass media programme can effectively motivate smokers to initiate an attempt to quit.^14,15,16 CA also pioneered the Smokers'' Helpline, an evidence‐based cessation approach^17,18 that has been an integral part of the CA Tobacco‐Control Program since 1993.¹⁹ In addition, CA passed the first state‐wide law banning smoking in the workplace in 1995, and there is mounting evidence that smoke‐free workplaces encourage smoking cessation.²⁰ Thus, it might be expected that CA would have higher rates of successful smoking cessation than states without such a comprehensive tobacco control programme.In comparison, the adjacent states of New York and New Jersey (NY & NJ) have a combined population size similar to CA, and both were similar to CA in the level of cigarette excise taxes during the 1980s and 1990s, yielding similar high cigarette prices.⁷ However, neither state supported a comprehensive tobacco‐control programme during the 1990s, with funding for tobacco control averaging about $0.20 per capita in NY during this time, and less in NJ (Ursula Bauer, personal communication 2005). It might be expected that NY & NJ would have lower rates of smoking cessation than CA and higher cessation rates than states with lower excise taxes and cigarette prices during the study period.A third contrasting group are the six US states that accounted for >90% of tobacco production in the US during the study period.²¹ These have consistently had among the lowest excise taxes and cigarette prices in the nation,⁷ and none had a state‐specific tobacco‐control programme in the 1990s. In addition, evidence suggests that social norms are more supportive of tobacco use in tobacco‐growing regions.²² These tobacco‐growing states (TGS) are Kentucky, Tennessee, North Carolina, South Carolina, Virginia and Georgia, which together have a population slightly larger than CA, or NY & NJ. These states might be expected to show the lowest rates of successful smoking cessation during the study period.In this report, we assess changes in rates of successful smoking cessation from the 1980s to the 1990s in the US as a whole. We consider trends in cessation rates for three age groups of smokers: young adults (20–34?years), early middle‐aged adults (35–49?years) and late middle‐aged adults (50–64?years). We then compare rates of cessation in the 1990s for the three comparison groups of states: CA (high cigarette price and a comprehensive tobacco‐control programme), NY & NJ (high price but no comprehensive programme) and the TGS (neither high price nor programme). We limit consideration to non‐Hispanic whites because of considerable differences in tobacco‐use behaviour among race or ethnic groups that may confound the analysis,²³ and do not assess trends in cessation within state groups because of small sample sizes.