摘要：Objectives. We determined the impact of smoke-free municipal public policies on hospitalizations for chronic obstructive pulmonary disease (COPD). Methods. We conducted a secondary analysis of hospital discharges with a primary diagnosis of COPD in Kentucky between July 1, 2003, and June 30, 2011 using Poisson regression. We compared the hospitalization rates of regions with and without smoke-free laws, adjusting for personal and population covariates, seasonality, secular trends over time, and geographic region. Results. Controlling for covariates such as sex, age, length of stay, race/ethnicity, education, income, and urban–rural status, among others, we found that those living in a community with a comprehensive smoke-free law or regulation were 22% less likely to experience hospitalizations for COPD than those living in a community with a moderate–weak law or no law. Those living in a community with an established law were 21% less likely to be hospitalized for COPD than those with newer laws or no laws. Conclusions. Strong smoke-free public policies may provide protection against COPD hospitalizations, particularly after 12 months, with the potential to save lives and decrease health care costs. Chronic obstructive pulmonary disease (COPD) is a serious, chronic, progressive lower respiratory disorder characterized by airflow limitation with varying degrees of chronic bronchitis and emphysema. The primary risk factor for COPD is cigarette smoke, with either direct exposure (firsthand smoking) or indirect exposure through secondhand smoke. 1–3 COPD is a leading cause of physician office visits 4 and emergency department visits, 5 and it is a primary cause of hospitalization in older adults. 4 COPD is also associated with more comorbidities, 6 reduced quality of life, 7 decreased functional status, 8 depression, 7 and cognitive deficits. 9 In 2010, the economic burden associated with COPD was approximately $50 billion, including $29.5 billion for direct care, $8 billion in indirect morbidity costs, and $12.4 billion for indirect mortality costs. 10 The health care costs associated with COPD for the next 2 decades are projected to be $800 billion. 11 Although many states and local US communities have enacted comprehensive smoke-free workplace laws, southern, rural tobacco-growing states and locales lag behind in smoking cessation rates and protection of workers from exposure to secondhand smoke. The worldwide prevalence of COPD is estimated at 10.1%. 12 By comparison, the prevalence of COPD in southeastern Kentucky, a rural tobacco-growing state, is nearly double at 19.6%. 13 COPD is currently the third leading cause of death in Kentucky and the United States, 14,15 and 9.3% of Kentucky adults have been told by a provider that they have COPD. 16 Kentucky is a national leader in smoking prevalence, with 29% of adults reporting current tobacco use. 17 One fourth (25%) of Kentucky high school students and 12% of middle school students are current cigarette smokers. 18 As of December 1, 2013, 66% of Kentuckians were regularly exposed to secondhand smoke in workplaces and public places. 19 Previous studies have shown a decrease in hospitalization 20–22 and mortality rates 23 for respiratory diseases after smoke-free legislation. As of June 30, 2011, communities in 28 Kentucky counties had enacted smoke-free laws or adopted Board of Health regulations limiting exposure to some degree. The first ordinance was implemented in Lexington-Fayette County in April 2004, 24 with the majority of public policies taking effect in 2008–2011. The most comprehensive ordinances and regulations, 100% smoke-free workplace and 100% smoke-free enclosed public place laws, were implemented in communities in 16 counties, covering more than 30% of the state’s population. Moderate smoke-free ordinances and 100% smoke-free enclosed public place laws including restaurants and bars, but not all workplaces, were in effect in 3 counties. Communities in 9 counties had enacted weak smoke-free laws or regulations, protecting workers and patrons in some public and workplace venues with significant exemptions (e.g., age restrictions, enclosed smoking rooms, restaurants only). Laws or regulations in 11 of the 28 counties covered the entire county. Although some additional counties had very limited smoking restrictions that applied only to municipal buildings (not 100% public policies), we did not include these laws in the study. Given the prevalence of smoking and COPD in Kentucky, and the presence of local smoke-free public policies in some counties, we aimed to determine the impact of smoke-free laws in Kentucky on hospitalizations for COPD exacerbation. We hypothesized that areas with comprehensive smoke-free laws would have lower COPD-related hospitalizations than those with moderate–weak laws and those without laws, controlling for sex, age, length of stay, race/ethnicity, education, income, urban–rural status, primary care physician supply, heart disease, diabetes, smoking rate, quit attempt rate, seasonality, and region of residence. A secondary aim was to determine whether duration of law influenced COPD hospitalizations, controlling for these covariates. We hypothesized that communities with established laws would exhibit lower rates of COPD hospitalization than those with newer or no laws.
