Patterns of tobacco use

INTRODUCTION — Cigarette smoking is the leading preventable cause of mortality in the United States and worldwide, responsible for an estimated 7.7 million deaths worldwide each year and over 480,000 deaths each year in the United States [1,2]. Most smoking-related mortality is due to atherosclerotic cardiovascular disease (CVD), lung cancer, and chronic obstructive pulmonary disease (COPD) [3]. Tobacco use also increases the risk of many other acute and chronic diseases, including cancers at many sites other than the lung [2]. Smoking cessation increases life expectancy by as much as a decade, is associated with clear health benefits, improves quality of life, and should always be a major health care goal [2,4].

Screening all patients for tobacco use and providing all individuals who smoke a brief smoking cessation intervention are among the most cost-saving clinical preventive services and has the highest evidence rating (Grade A) from the US Preventive Services Task Force [5,6]. (See "Overview of smoking cessation management in adults".)

In the United States, use of non-cigarette forms of tobacco and use of multiple tobacco products by the same individual is increasing; in 2019, 40 percent of tobacco users used tobacco in more than one form [7].

The prevalence and patterns of tobacco use in adults are reviewed here. Patterns of smoking in children and adolescents are presented separately. (See "Prevention of smoking and vaping initiation in children and adolescents", section on 'Epidemiology'.)

The risks of smoking are discussed separately:

●(See "Cardiovascular risk of smoking and benefits of smoking cessation".)

●(See "Cardiovascular effects of nicotine".)

●(See "Cigarette smoking and other possible risk factors for lung cancer".)

●(See "Cigarette and tobacco products in pregnancy: Impact on pregnancy and the neonate".)

ASSESSMENT OF USE — In the United States, tobacco product usage is assessed by several large cross-sectional and nationally-representative surveys, in which respondents self-report their use of various tobacco products. The annual National Health Interview Survey (NHIS) is used most commonly to benchmark tobacco use rates [8]; in 2019, the NHIS reported that nearly 21 percent of United States adults used tobacco products [8].

CIGARETTE USE

Tobacco cigarettes — Cigarettes remain the most common tobacco product used in the United States, although an increasing proportion of tobacco users are using multiple products, most often cigarettes and electronic cigarettes (e-cigarettes) [7]. Alternate forms of tobacco are shown in a table (table 1). Cigarettes also remain the most common tobacco product used worldwide [9].

Prevalence — In 2019, an estimated 1.1 billion individuals worldwide smoked tobacco products. The global smoking prevalence was 33 percent among men and 7 percent among women [9]. In most countries, there has been a decline in smoking prevalence since 1990. However, there is great variability in tobacco use among countries, with smoking prevalence greater in low- to middle-income countries, where an estimated 80 percent of the world’s tobacco users live, compared with high-income countries [9].

The prevalence of cigarette smoking among adults in the United States has declined dramatically from its peak of 42.4 percent in 1965 [8,10]. In 2019, an estimated 21 percent of US adults (51 million individuals) were current users of any tobacco product; 80 percent of users (17 percent of all US adults) used a combustible tobacco product (cigarettes, cigars, or pipes) [8]. In 2019, 14 percent of adults in the United States, an estimated 34 million individuals, smoked tobacco cigarettes every day or some days [8]. The rate of adult tobacco product use varies widely between regions: it is higher among those living in the Midwest and South (24 and 23 percent) compared with those living in the Northeast and West (19 and 16 percent).

Smoking rates worldwide vary according to sociodemographic factors. In the Global Burden of Disease (GBD) study, income, educational attainment, and fertility rates were used to create a composite indicator called the sociodemographic index (SDI), and countries were stratified into five quintiles, with a lower SDI reflecting lower income and education and higher fertility rates [11]. Globally, smoking prevalence was generally higher among those in the higher SDI quintiles and lowest in the low SDI quintile.

By contrast, in the United States, the relationship between sociodemographic factors and smoking rates is reversed. According to the National Health Interview Survey (NHIS), 35 percent of adults who have passed the General Education Development (GED) test smoke cigarettes, compared with 7 percent of adults with a college degree [8]. Furthermore, in the United States, adults with lower incomes are more likely to smoke than those with higher incomes [8].

Although the sex gap in cigarette smoking rates has narrowed over time (figure 1), in 2019, males in the United States were more likely than females to use any tobacco product (26 percent versus 16 percent) and to smoke cigarettes (15 percent versus 13 percent) [8]. Tobacco use also varies by age, with higher use in young and middle-aged adults aged 25 to 64 years (20 percent) compared with the youngest adults aged 18 to 24 years (11 percent) and oldest adults aged ≥ 65 (10 percent) [8].

In the United States, there is considerable variation in rates and types of tobacco product use among adults working in different occupations and industries. As examples, rates of cigarette smoking are higher among construction workers and in those in the accommodation and food services industry (24 to 26 percent) and lower in the education services industry and among life, physical, and social science workers (6 to 7 percent) [12].

In the United States, American Indian/Alaskan Native individuals have the highest prevalence of smoking, non-Hispanic Black individuals and non-Hispanic White individuals have a lower smoking prevalence, and Hispanic and non-Hispanic Asian individuals are least likely to be smokers [7,8,13]. Tobacco use rates in the United States also vary by sexual orientation, with higher use among lesbian, gay, and bisexual adults than among heterosexual adults (30 versus 21 percent) [8,10]. Adults with disabilities and anxiety disorders also use tobacco at higher rates than adults without these conditions.

Age of onset — The majority of US adults who smoke start smoking by the age of 18 [14,15], and the younger a person begins smoking, the more likely they are to continue smoking into adulthood [5]. Smoking in children and adolescents is discussed separately. (See "Prevention of smoking and vaping initiation in children and adolescents", section on 'Epidemiology'.)

Electronic cigarettes — E-cigarettes are electronic devices that use a battery to heat a liquid, producing an aerosol that users inhale. The vapor looks like smoke but is neither smoke nor the product of any combustion [16]. In most cases, the liquid used in the devices contains nicotine, in which case the devices may be called electronic nicotine delivery systems (ENDS). E-cigarettes are discussed in detail elsewhere. (See "Vaping and e-cigarettes".)

Heat-not-burn tobacco products — Heat-not-burn (HNB) tobacco products use an electric blade to heat a tobacco stick to a temperature below that at which tobacco burns in order to avoid producing smoke. HNB tobacco products are available in several countries, and the US Food and Drug Administration (FDA) authorized the first of these products for sale in the United States in 2019 [17].

A laboratory study showed that HNB tobacco cigarettes release an aerosol containing lower amounts of harmful constituents than are found in conventional tobacco cigarette smoke [18], which may translate to a lower level of health risks than continuing to smoke combustible cigarettes. However, because these products are new to the market, evidence about their health risks is very limited.

OTHER FORMS OF TOBACCO — Tobacco in other forms, including cigar, hookah/water pipe, and smokeless tobacco (SLT), constitutes a considerable portion of tobacco use in the United States (table 1). In 2019, cigars, cigarillos, and filtered little cigars were used by 3.6 percent; smokeless tobacco by 2.4 percent; and pipes, water pipes or hookahs by 1.0 percent of United States adults [8]. In 2019, 19 percent of current users reported using two or more types of tobacco products. In 2014, the most frequent combination was cigarettes and electronic cigarettes (e-cigarettes), used by almost one-quarter of those reporting dual use [7].

Cigars and pipes — Consumption of cigars in the United States increased between 2000 and 2012 after which it began to decline (figure 2). A longitudinal tobacco use study conducted in the United States from 2013 to 2014 found 8 percent of adults smoked cigars, in the form of traditional cigars, cigarillos, or filtered cigars, with the heaviest usage among young adults 18 to 24, at 14 percent [7]. Pipe tobacco usage in that study was considerably lower, at 1 percent of adults.

The smoke from cigars and pipes is not typically inhaled as deeply into the lungs as is cigarette smoke and, for this reason, the risk of developing lung cancer from smoking cigars and pipes is lower than the risk from smoking cigarettes but higher than the risk for a nonsmoker [19]. (See "Cigarette smoking and other possible risk factors for lung cancer", section on 'Cigar and pipe smoking' and "Epidemiology and risk factors for head and neck cancer", section on 'Tobacco products'.)

Waterpipes or hookahs — The use of a water pipe, also known as a hookah, is increasing in the United States, especially among young adults, with a prevalence of 18 percent among 18- to 24-year-olds [7,20]. The water pipe, a traditional form of tobacco use in the Middle East, uses charcoal to heat tobacco, creating smoke that first passes through a water vessel before being inhaled.

The amount of nicotine and toxins varies based on the type of tobacco used and how it is smoked. Water pipe smoking is associated with lung cancer, carbon monoxide poisoning, and other respiratory diseases [21,22]. In one meta-analysis including six cross-sectional studies, water pipe smoking was associated with negative effects on lung function including a reduction in forced expiratory volume in one second (FEV1) [23]. Water pipe smoking is likely to be a cause of obstructive lung disease. (See "Office spirometry", section on 'Forced expiratory volume in one second'.)

Smokeless tobacco — Smokeless tobacco (SLT) products are put in the mouth and are available in several forms including chewing tobacco and snuff/snus pouches. In 2018, 2.4 percent of adults in the United States used SLT products [7,10]. Snuff/snus pouch use is increasing, and chewing tobacco use is declining (figure 3) [24].

The Population Assessment of Tobacco and Health Study (PATH) in the United States surveyed over 32,000 adults, finding that more than one tobacco product is used by 75 percent of SLT users [25]. Approximately half also used cigarettes, cigars, or more than one form of SLT [25]. SLT was used most commonly by White males of lower socioeconomic status in non-urban areas and in the southern United States [7,25].

SLT products provide sufficient nicotine exposure to cause nicotine addiction. Different processing techniques for SLT, particularly "curing," can result in markedly different contents of toxins in SLT products. SLT causes cancer of the oral cavity [26] and may be associated with increased risk for cardiovascular disease [27,28]. However, the health risks for certain diseases may be substantially less with SLT than with smoking [29,30]. Risks related to specific diseases are discussed in detail elsewhere. (See "Epidemiology and risk factors for head and neck cancer", section on 'Tobacco products' and "Cardiovascular effects of nicotine", section on 'Other nicotine products and cardiovascular risk'.)

CHILDREN AND ADOLESCENTS — Patterns and risk factors for smoking in children and adolescents are presented separately. (See "Prevention of smoking and vaping initiation in children and adolescents", section on 'Epidemiology'.)

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Smoking cessation, e-cigarettes, and tobacco control".)

INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5^th to 6^th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10^th to 12^th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)

●Basics topics (see "Patient education: Quitting smoking (The Basics)")

●Beyond the Basics topics (see "Patient education: Quitting smoking (Beyond the Basics)")

SUMMARY AND RECOMMENDATIONS

●Risks of tobacco use – Cigarette smoking is the leading preventable cause of mortality in the United States and worldwide. Most smoking-related mortality is due to atherosclerotic cardiovascular disease (CVD), cancer, and chronic obstructive pulmonary disease (COPD). Tobacco use also increases the risk of many other diseases, including cancer at many sites other than the lung. (See 'Introduction' above.)

●Patterns and prevalence of tobacco product use – Worldwide, 33 percent of males and 7 percent of females smoke tobacco; the prevalence of cigarette use has declined in most countries, including the United States. Cigarettes remain the most common form of tobacco use in the United States, used by 14 percent of adults. In the United States, almost 21 percent of adults use any tobacco product, and among tobacco product users, 19 percent use a combination of products. The most frequent combination is cigarettes and electronic cigarettes (e-cigarettes). (See 'Cigarette use' above and 'Other forms of tobacco' above.)

●Age of smoking onset impacts adult tobacco use – Almost every adult who smokes cigarettes started smoking by the age of 18. The earlier the age at which a person begins to smoke, the more likely they are to continue smoking into adulthood. (See 'Age of onset' above.)

●Other tobacco products – In addition to cigarettes, tobacco is also smoked in cigars, pipes, and hookahs/water pipes. Tobacco is also used in non-combustible forms. One of these includes smokeless tobacco (SLT), which generally comes as chewing tobacco or snuff/snus pouches. Other non-combustible tobacco products include heat not burn (HNB) tobacco products and e-cigarettes, devices that heat a nicotine-containing liquid to produce an aerosol that resembles but is not smoke because no combustion has occurred. Alternate forms of tobacco are shown in a table (table 1). (See 'Other forms of tobacco' above.)

ACKNOWLEDGMENT — The UpToDate editorial staff acknowledges Dr. Stephen Rennard, MD, and Mr. David Daughton, MS, who contributed to an earlier version of this topic review.