State-Specific Secondhand Smoke Exposure and Current Cigarette Smoking Among Adults—United States, 2008 FREE

MMWR. 2009;58:1232-1235

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Secondhand smoke (SHS) causes immediate and long-term adverse health effects in nonsmoking adults and children, including heart disease and lung cancer, and SHS exposure occurs primarily in homes and workplaces.¹ Smoke-free policies, including not allowing smoking anywhere inside the home (i.e., having a smoke-free home rule), are the best way to provide protection from exposure to SHS. To assess SHS exposure in homes and indoor workplaces and the prevalence of smoke-free home rules, CDC analyzed 2008 Behavioral Risk Factor Surveillance System (BRFSS) data from 11 states and the U.S. Virgin Islands (USVI). This report summarizes the results, which showed wide variation among states in exposure to SHS in homes (from 3.2% [Arizona] to 10.6% [West Virginia]) and indoor workplaces (from 6.0% [Tennessee] to 17.3% [USVI]). The majority of persons surveyed in the 11 states and USVI reported having smoke-free home rules (from 68.8% [West Virginia] to 85.7% [USVI]). This report also provides the 2008 results for CDC's annual BRFSS-based state-specific estimates of current smoking in 50 states, the District of Columbia (DC), and three territories (Guam, Puerto Rico, and USVI). As in previous years, the results showed substantial variation in self-reported cigarette smoking prevalence (range: 6.5%-27.4%; median for 50 states and DC = 18.4%). Additional legislation is needed to increase the number of smoke-free workplaces and other public places. Health-care providers should continue to encourage persons to make their homes completely smoke-free.

State variation exists in the prevalence of current smoking, in nonsmoker exposure to secondhand smoke, and in the prevalence of persons who have completely smoke-free rules for their homes.

What is added by this report?

Among 11 states and the U.S. Virgin Islands (USVI), nonsmoker exposure to secondhand smoke in their homes ranged from 3.2% (Arizona) to 10.6% (West Virginia), exposure in their indoor workplaces ranged from 6.0% (Tennessee) to 17.3% (USVI), and the percentage of the population with smoke-free home rules ranged from 68.8% (West Virginia) to 85.7% (USVI).

What are the implications for public health practice?

Establishing smoke-free workplaces and promotion of smoke-free home rules should be continued and expanded to protect nonsmokers from secondhand smoke and reduce smoking prevalence.

BRFSS* conducts state-based, random-digit–dialed telephone surveys of the noninstitutionalized U.S. population aged ≥18 years to collect data on health conditions and health risk behaviors. The 2008 BRFSS included data from 414,509 respondents, which were used to assess current smoking prevalence.† The questions to assess SHS exposure and home smoking rules‡ were offered to states as an optional module and were used by 11 states and USVI, which combined represented approximately 19% of the U.S. adult population in 2008.

BRFSS estimates were weighted to the respondent's probability of being selected and the age-, sex-, and race/ethnicity-specific populations from 2008 estimates projected from the 2000 Census for each state, DC, and the U.S. territories. These sampling weights were used to calculate all estimates and 95% confidence intervals. Response rates for BRFSS are calculated using Council of American Survey and Research Organizations (CASRO) guidelines.§ Median survey response rates were 53.3% and median cooperation rates were 75.0%. For comparisons of prevalence between males and females and smokers and nonsmokers statistical significance (p<0.05) was determined using a two-sided z-test.

In the 11 states and USVI, the percentage of persons who reported being exposed to SHS inside their home ranged from 3.2% (Arizona) to 10.6% (West Virginia) (median: 7.8%), and SHS exposure in indoor workplaces ranged from 6.0% (Tennessee) to 17.3% (USVI) (median: 8.6%). The percentage of persons who reported that smoking was not allowed anywhere inside their home ranged from 68.8% (West Virginia) to 85.7% (USVI) (median: 78.1%). In all states, nonsmokers (range: 80.4% [West Virginia] to 89.3% [Arizona]; median: 84.7%) were more likely to report having a smoke-free home than smokers (range: 36.4% [West Virginia] to 66.0% [Arizona]; median: 45.0%).

In 2008, the median prevalence of adult current smoking in the 50 states and DC was 18.4%. Among states, current smoking prevalence was highest in West Virginia (26.6%), Indiana (26.1%), and Kentucky (25.3%); and lowest in Utah (9.2%), California (14.0%), and New Jersey (14.8%). Smoking prevalence was 6.5% in USVI, 11.6% in Puerto Rico and 27.4% in Guam. Median smoking prevalence for the 50 states and DC was 20.4% for men and 16.7% for women. Men had a statistically higher prevalence of smoking than women in 35 states, DC, and the three territories.

A Malarcher, PhD, N Shah, BDS, M Tynan, E Maurice, MS, V Rock, MPH, Office on Smoking and Health, National Center for Chronic Disease Prevention and Health Promotion, CDC.

Millions of persons in the United States are still exposed to SHS in their homes and workplaces.¹ The results of this analysis indicate that, in 2008, across the 11 states and USVI, prevalence of exposure to SHS varied by more than threefold at home, and more than twofold at work. These variations in SHS exposures are related to differences in state smoking prevalence; state smoking restrictions for private-sector worksites, restaurants, and bars; the prevalence of smoke-free home rules; and the level of enforcement of these restrictions and home rules.¹ The prevalence of smoke-free households and the number and restrictiveness of state laws regulating smoking in private-sector worksites, restaurants, and bars has increased substantially over time.^1- 3 For example, during December 31, 2004–December 31, 2007, the level of smoking restrictions became more protective for private-sector worksites in 18 states, for restaurants in 18 states, and for bars in 12 states.³ Nevertheless, state tobacco control programs need to continue to encourage the public to make their homes smoke-free and more states need to enact legislation that eliminates smoking in private-sector worksites, restaurants, and bars.¹

The most recent national estimates to which the state-specific SHS home exposure results can be compared are from the 1999-2004 National Health and Nutrition Examination Survey (NHANES), which consists of a series of cross-sectional surveys that include a household interview and standardized physical examinations.⁴ The NHANES measure of nonsmokers' SHS exposure at home was based on the self-reported presence of at least one household member who smokes in the home. The NHANES data indicate that among nonsmokers aged >4 years, self-reported SHS exposure within the home declined significantly from 1988-1994 (20.9%) to 1999-2004 (10.2%).⁴ These declines are reflected in serum cotinine measurements from NHANES nonsmokers' blood samples (serum cotinine levels are an objective measure of exposure to nicotine during the past 3-4 days). The percentage of nonsmokers aged >4 years with detectable serum cotinine (>0.05 ng/mL) declined from 83.9% in 1988-1994 to 46.4% in 1999-2004.⁴

The percentage of persons who report that their home has a smoke-free rule has increased substantially over time.^1- 2 For example, data from BRFSS indicate that, among the five states and USVI that assessed smoke-free home rules in both the 2005 and 2008 BRFSS, four states (New Jersey, North Carolina, Virginia, and West Virginia) had a statistically significant (p<0.05) increase in prevalence of smoke-free homes, ranging from a percentage point increase of 1.9% to 3.5%.⁵∥ In general, the prevalence of exposure to smoke in the home is higher in homes with less restrictive smoking rules.¹

SHS exposure at work is related to the level of restrictions states and communities place on smoking in worksites (including private-sector sites, restaurants, and bars) and levels of enforcement of those restrictions.¹ State laws varied across the 11 states included in this analysis and ranged from no statewide smoking restrictions in any venue (Indiana, Mississippi, North Carolina, and West Virginia) to states that are 100% smoke-free in private-sector worksites, restaurants, and bars (Arizona and New Jersey) (3).¶ Two of the 11 states, North Carolina and Virginia, enacted more restrictive laws during 2009. North Carolina's law# will require restaurants and bars to be 100% smoke-free, effective January 2, 2010. Virginia's law,** which will take effect on December 1, 2009, sets limited restrictions and will allow separate ventilated smoking rooms in restaurants and bars. As of October 1, 2009, only 21 states and DC have laws that make indoor public places and worksites completely smoke-free, and although most laws are adequately complied with, enforcement remains an issue in some settings.^1,3 Separating smokers from nonsmokers, use of air cleaning technologies, and ventilating buildings cannot eliminate exposure to SHS.¹ According to the U.S. Surgeon General, smoke-free policies that prohibit smoking in all indoor areas are the only effective approach to ensure that SHS exposure does not occur in workplaces and other public places.¹

The analysis of 2008 current smoking prevalence indicated that state levels and trends continued to vary substantially.⁶ In 2008, Utah and USVI continued to meet the Healthy People 2010 objective (27-1a) to reduce cigarette smoking by adults to ≤12% (met since 2003 in Utah and since 2001 in USVI).^6- 7 Puerto Rico met this objective for the first time in 2008. Trends since 1998 indicate that few other states are likely to meet the Healthy People target by 2010.⁶

The BRFSS median for the prevalence of current smoking across the 50 states and DC (18.4%) differs from the mean prevalence of current smoking among adults aged ≥18 years from the 2008 National Health Interview Survey (NHIS) (20.6%). The national mean from BRFSS was not reported because the focus of BRFSS is on state-level estimates. In contrast, NHIS mean prevalence serves as the national measure for tracking progress toward Healthy People 2010 objectives.⁷ For BRFSS analyses, each state draws its own independent sample to produce a state-level estimate. A number of differences between the two surveys exist, including survey type (telephone versus household), variations in response rates, and sampling and weighting procedures.

The findings in this report are subject to at least four limitations. First, BRFSS does not sample persons in households without any telephone service (1.9%) or with only wireless telephones (20.2%), and adults with only wireless service are more likely (26.5%) than the rest of the U.S. population to be current smokers; therefore, current smoking prevalence might be underestimated.⁸ Second, estimates for cigarette smoking are based on self-report and are not validated by biochemical tests. However, self-reported data on current smoking status have high validity.⁹ Similarly, estimates of exposure to SHS at home and in the workplace also were assessed by self-report, which might underestimate the proportion exposed when compared with serum cotinine measurement.¹ Third, the median response rate in all states and DC was 53.3% (range: 35.8%-65.9%). Low response rates might indicate a potential for response bias such that smoking prevalence might be underestimated if smokers are less likely to respond to a survey. Finally, SHS exposure at home and in the workplace was assessed for the 7 days preceding the survey. This might underestimate exposure if a person who usually smoked in these locations was absent during that week.

Enacting legislation that eliminates smoking in indoor work spaces and public places and encouraging persons to implement smoke-free home rules will protect persons from exposure to SHS.¹ The Institute of Medicine recently concluded that SHS exposure can cause acute myocardial infarction (AMI) and that communities that enact smoke-free policies realize a reduction in hospitalization for AMI among the general population.¹⁰ All persons, including those with an increased risk for heart disease, can protect themselves from SHS exposure by avoiding indoor areas that allow smoking.

*BRFSS survey data information available at http://www.cdc.gov/brfss/technical_infodata/surveydata/2008.htm.

†Those respondents who answered “yes” to the question “Have you smoked at least 100 cigarettes in your entire life?” and answered “every day” or “some days” to the question “Do you now smoke cigarettes every day, some days, or not at all?” were classified as current cigarette smokers. Persons who reported either never having smoked 100 cigarettes (never smokers) in their life or those who had smoked but were not current smokers (former smokers) together were classified as nonsmokers.

‡Exposure to SHS at home was determined by asking, “On how many of the past 7 days, did anyone smoke in your home while you were there?” Exposure to SHS in indoor workplaces was determined by asking the respondents, “On how many of the past 7 days, did someone smoke in your indoor workplace while you were there?” Nonsmokers who reported >1 day of exposure were classified as being exposed to SHS. To assess rules about smoking in their home, respondents were asked “Which statement best describes the rules about smoking inside your home? Do not include decks, garages, or porches (Smoking is not allowed anywhere inside my home, Smoking is allowed in some places or at some times, Smoking is allowed anywhere inside my home, or There are no rules about smoking inside my home).”

§The response rate is the percentage of persons who completed interviews among all eligible persons, including those who were not successfully contacted. The cooperation rate is the percentage of persons who completed interviews among all eligible persons who were contacted.

∥The 2005 question was “Which statement best describes the rules about smoking inside your home?” with response options “Smoking is not allowed anywhere inside your home,” “Smoking is allowed in some places or at some times,” “Smoking is allowed anywhere inside your home,” and “There are no rules about smoking inside your home.”

¶The CDC State Tobacco Activities Tracking and Evaluation (STATE) System. Atlanta, GA: US Department of Health and Human Services, CDC; 2009. Available at http://apps.nccd.cdc.gov/statesystem contains information on state smoke-free laws.

#NC H.B. 2, Session Law 2009-27.

**VA H.B. 1703, Chapter 153.