Use Of Non-cigarette Tobacco Products Research Articles

Association of Noncigarette Tobacco Product Use With Future Cigarette Smoking Among Youth in the Population Assessment of Tobacco and Health (PATH) Study, 2013-2015

Approximately 90% of adult smokers first tried a cigarette by 18 years of age, and even infrequent smoking in adolescence is associated with established adult smoking. Noncigarette tobacco use is increasing and could stimulate subsequent conventional cigarette smoking in youths. To estimate the longitudinal association between noncigarette tobacco use and subsequent cigarette smoking initiation among US youth. In this prospective cohort study of the Population Assessment of Tobacco and Health (PATH) waves 1 (September 12, 2013, to December 14, 2014) and 2 (October 23, 2014, to October 30, 2015), a nationally representative sample of youths who never smoked a conventional cigarette at baseline and completed wave 2 follow-up (N = 10 384) was studied. PATH retention at follow-up was 87.9%. Ever use and past 30-day use of electronic cigarettes (e-cigarettes), hookah, noncigarette combustible tobacco, or smokeless tobacco at baseline. Ever use and past 30-day use of cigarettes at follow-up. The present analysis was based on the 10 384 PATH youth respondents who reported never having smoked a cigarette in wave 1 and whose cigarette ever or past 30-day use was reported in wave 2 (mean [SD] age, 14.3 [1.7] years; age range, 12-17 years; 5087 [49.1%] female; 4829 [52.5%] white). At 1-year follow-up, 469 (4.6%) of all baseline never-smoking youths had tried a cigarette and 219 (2.1%) had smoked a cigarette within the past 30 days. Cigarette ever use at follow-up was higher among youths who had ever used e-cigarettes (78 [19.1%]), hookah (60 [18.3%]), noncigarette combustible tobacco (45 [19.2%]), or smokeless tobacco (29 [18.8%]) at baseline. After adjusting for sociodemographic, environmental, and behavioral smoking risk factors and for baseline ever use of other tobacco products, the odds of past 30-day cigarette use at follow-up were approximately twice as high among baseline ever users of e-cigarettes (odds ratio [OR], 1.87; 95% CI, 1.15-3.05), hookah (OR, 1.92; 95% CI, 1.17-3.17), noncigarette combustible tobacco (OR, 1.78; 95% CI, 1.00-3.19), and smokeless tobacco (OR, 2.07; 95% CI, 1.10-3.87). Youths who had tried more than 1 type of tobacco product at baseline had 3.81 (95% CI, 2.22-6.54) greater adjusted odds of past 30-day cigarette smoking at follow-up than did baseline never tobacco users. Any use of e-cigarettes, hookah, noncigarette combustible tobacco, or smokeless tobacco was independently associated with cigarette smoking 1 year later. Use of more than 1 product increased the odds of progressing to cigarette use.

Tobacco Use Among Working Adults - United States, 2014-2016.

Cigarette smoking has declined considerably among U.S. adults over several decades (1); however, increases have occurred in the use of noncigarette tobacco products in recent years, and the use of multiple tobacco products has become common among current users of noncigarette tobacco products (2,3). Differences in tobacco use have also been observed across population subgroups, including among working adults (2,4). CDC analyzed National Health Interview Survey (NHIS) data for 2014-2016 to describe the most recent prevalence estimates of current (every day or some days) tobacco product use among working U.S. adults by industry and occupation. Among working adults, 22.1% (32.7 million) currently used any form of tobacco; 15.4% used cigarettes, 5.8% used other combustible tobacco (cigars, pipes, water pipes or hookahs, very small cigars, and bidis), 3.0% used smokeless tobacco, and 3.6% used electronic cigarettes (e-cigarettes); 4.6% (6.9 million) reported current use of two or more tobacco products. By industry, any tobacco use ranged from 11.0% among education services to 34.3% among construction workers; current use of two or more tobacco products was highest among construction workers (7.1%). By occupation, any tobacco use ranged from 9.3% among life, physical, and social science workers to 37.2% among installation, maintenance, and repair workers; current use of two or more tobacco products was highest among installation, maintenance, and repair workers (10.1%). Proven interventions to prevent and reduce tobacco product use, including current use of multiple products, among working adults are important (5,6). Workplace tobacco-control interventions have been especially effective in reducing cigarette smoking prevalence (7).

Co-occurrence of tobacco product use, substance use, and mental health problems among youth: Findings from wave 1 (2013–2014) of the population assessment of tobacco and health (PATH) study

IntroductionCigarette use is associated with substance use and mental health problems among youth, but associations are unknown for non-cigarette tobacco product use, as well as the increasingly common poly-tobacco use. MethodsThe current study examined co-occurrence of substance use and mental health problems across tobacco products among 13,617 youth aged 12–17years from Wave 1 (2013–2014) of the nationally representative Population Assessment of Tobacco and Health (PATH) Study. Participants self-reported ever cigarette, e-cigarette, smokeless tobacco, traditional cigar, cigarillo, filtered cigar, hookah, and other tobacco product use; alcohol, marijuana, and other drugs; and lifetime substance use, internalizing and externalizing problems. ResultsIn multivariable regression analyses, use of each tobacco product was associated with substance use, particularly cigarillos and marijuana (AOR=18.9, 95% CI: 15.3–23.4). Cigarette (AOR=14.7, 95% CI: 11.8–18.2) and cigarillo (AOR=8.1, 95% CI: 6.3–10.3) use were strongly associated with substance use problems and tobacco users were more likely to report internalizing (AOR=1.6, 95% CI: 1.4–1.8) and externalizing (AOR=1.4, 95% CI: 1.3–1.6) problems. Female tobacco users were more likely to have internalizing problems than male tobacco users. Poly-tobacco users were more likely than exclusive users to use substances (AOR=3.4, 95% CI: 2.7–4.3) and have mental health (AOR=1.2, 95% CI: 1.0–1.5) and substance use (AOR=4.7, 95% CI: 3.4–6.6) problems. ConclusionsRegardless of the tobacco product used, findings reveal high co-occurrence of substance use and mental health problems among youth tobacco users, especially poly-tobacco users. These findings suggest the need to address comorbidities among high risk youth in prevention and treatment settings.

Co-occurrence of tobacco product use, substance use, and mental health problems among adults: Findings from Wave 1 (2013–2014) of the Population Assessment of Tobacco and Health (PATH) Study

BackgroundAlthough non-cigarette tobacco product use is increasing among U.S. adults, their associations with substance use and mental health problems are unclear. This study examined co-occurrence of tobacco use, substance use, and mental health problems, and its moderation by gender, among 32,202U.S. adults from Wave 1 (2013–2014) of the nationally representative longitudinal Population Assessment of Tobacco and Health (PATH) Study. MethodsParticipants self-reported current cigarette, e-cigarette, traditional cigar, cigarillo, filtered cigar, hookah, smokeless tobacco and other tobacco product use; past year alcohol, marijuana, and other drug use; and past year substance use, internalizing and externalizing problems. ResultsCompared to non-current tobacco users, current users were more likely to report alcohol or drug use (adjusted odds ratio (AOR)=2.6; 95% confidence interval (CI): 2.3, 2.9), with the strongest associations observed for cigarillo and hookah users. Across all tobacco product groups, users were more likely to report internalizing (AOR=1.9; 95% CI: 1.7, 2.1), externalizing (AOR=1.6; 95% CI: 1.5, 1.8), and substance use (AOR=3.4; 95% CI: 2.9, 4.1) problems than non-users. Gender moderated many of these associations and, of these, all non-cigarette tobacco product associations were stronger among females. ConclusionsThis nationally representative study of U.S. adults is the first to comprehensively document tobacco use, substance use, and mental health comorbidities across the range of currently available tobacco products, while also demonstrating that female tobacco users are at increased risk for substance use and mental health problems. These findings may point to gender differences in vulnerability and suggest that interventions incorporate gender-specific approaches.

Sexual and Gender Minority College Students and Tobacco Use in Texas.

Most research regarding sexual and gender minority (SGM) populations is limited to examination of cigarette or general tobacco use or does not examine heterogeneity across SGM groups other than lesbian or gay and bisexual individuals. This study examined differences in the odds of current use and age of initiation of five tobacco/nicotine products among three groups of SGM young adults who self-identified as (1) gay or lesbian, (2) bisexual, and (3) queer, transgender, or "other," compared to their heterosexual peers. Participants were 4252 college students aged 18-29 years from 24 colleges in Texas who completed an online tobacco use survey. Multilevel logistic regression models were used to examine the odds of SGM participants currently using each tobacco product. Multilevel linear regression models were used to examine the association of current product users' SGM status with self-reported age of each product's initiation. All models were adjusted for sociodemographic factors and accounted for students clustered within each college. At least one SGM group had significantly greater odds of currently using every tobacco product type compared to heterosexual participants, except hookah. There were few differences across groups in age of initiation. However, queer, transgender, and "other-" identified participants initiated e-cigarettes 1.34 years younger than heterosexual participants, and bisexual participants initiated smokeless tobacco 3.66 years younger than heterosexual participants. Findings highlight some significant tobacco use disparities among SGM young adults compared to their heterosexual peers. Longitudinal studies with larger group sizes will identify prospective predictors of sustained SGM-related tobacco use disparities. This study extends the current literature by including the sexual and gender minority identity options of queer, transgender, and "other," highlighting disparities in tobacco use between young adults in these subgroups compared to their heterosexual peers, particularly in noncigarette tobacco product use. Findings underscore the need for the Food and Drug Association and other health agencies to tailor health communication efforts specific to sexual and gender minority populations pertaining to the risks and harms surrounding tobacco product use.

Sex Differences in Tobacco Use Among Persons Living With HIV/AIDS: A Systematic Review and Meta-Analysis.

Persons living with HIV/AIDS (PLWH) smoke at higher rates than other adults and experience HIV-related and non-HIV-related adverse smoking consequences. This study conducted a systematic review to synthesize current knowledge about sex differences in smoking behaviors among PLWH. Over 3000 abstracts from MEDLINE were reviewed and 79 publications met all the review inclusion criteria (ie, reported data on smoking behaviors for PLWH by sex). Sufficient data were available to conduct a meta-analysis for one smoking variable: current smoking prevalence. Across studies (n = 51), the meta-analytic prevalence of current smoking among female PLWH was 36.3% (95% confidence interval [CI]: 28.0% to 45.4%) and male PLWH was 50.3% (95% CI: 44.4% to 56.2%; meta-analytic odds ratio = 1.78, 95% CI: 1.29 to 2.45). When analyses were repeated just on the US studies (n = 23), the prevalence of current smoking was not significantly different for female PLWH (55.1%, 95% CI: 47.6% to 62.5%) compared with male PLWH (55.5%, 95% CI: 48.2% to 62.5%; meta-analytic odds ratio = 1.04, 95% CI: 0.86 to 1.26). Few studies reported data by sex for other smoking variables (eg, quit attempts, noncigarette tobacco product use) and results for many variables were mixed. Unlike the general US population, there was no difference in smoking prevalence for female versus male PLWH (both >50%) indicating that HIV infection status was associated with a greater relative increase in smoking for women than men. More research is needed in all areas of smoking behavior of PLWH to understand similarities and differences by sex to provide the best interventions to reduce the high smoking prevalence for all sexes.

Flavoured non-cigarette tobacco product use among US adults: 2013–2014

IntroductionLimited data exist on flavoured non-cigarette tobacco product (NCTP) use among US adults.MethodsData from the 2013 to 2014 National Adult Tobacco Survey (N=75 233), a landline and cellular telephone survey...

Openness to Using Non-cigarette Tobacco Products Among U.S. Young Adults.

National data indicate that the prevalence of non-cigarette tobacco product use is highest among young adults; however, little is known about their openness to use these products in the future and associated risk factors. This study sought to characterize openness to using non-cigarette tobacco products and associated factors among U.S. young adults. In 2014, National Adult Tobacco Survey data (2012-2013) were analyzed to characterize openness to using the following tobacco products among all young adults aged 18-29 years (N=5,985): cigars; electronic cigarettes ("e-cigarettes"); hookah; pipe tobacco; chew, snuff, or dip; snus; and dissolvables. Among those who were not current users of each product, multivariable logistic regression was used to examine associations between demographics, cigarette smoking status, lifetime use of other non-cigarette products, perceived harm and addictiveness of smoking, and receipt of tobacco industry promotions and openness to using each product. Among all young adults, openness to using non-cigarette tobacco products was greatest for hookah (28.2%); e-cigarettes (25.5%); and cigars (19.1%). In multivariable analyses, which included non-current users of each product, non-current ever, current, and former smokers were more likely than never smokers to be open to using most examined products, as were men and adults aged 18-24 years. Receipt of tobacco industry promotions was associated with openness to using e-cigarettes; chew, snuff, or dip; and snus. There is substantial openness to trying non-cigarette tobacco products among U.S. young adults. Young adults are an important population to consider for interventions targeting non-cigarette tobacco product use.

Trends in annual sales and current use of cigarettes, cigars, roll-your-own tobacco, pipes, and smokeless tobacco among US adults, 2002–2012

IntroductionRegulatory imbalances exist in the treatment of cigarettes and non-cigarette tobacco products in the USA. We assessed whether declines in cigarette consumption during 2002–2012 were offset by increased use of...

Prevalence and correlates of tobacco use among school-going adolescents in Madagascar

Approximately 90% of adults start smoking during adolescence, with limited studies conducted in low-and-middle-income countries where over 80% of global tobacco users reside. The study aims to estimate prevalence and identify predictors associated with adolescents’ tobacco use in Madagascar. We utilized tobacco-related information of 1184 school-going adolescents aged 13–15years, representing a total of 296,111 youth from the 2008 Madagascar Global Youth Tobacco Survey to determine the prevalence of tobacco use. Gender-wise multivariable logistic regression models were conducted to identify key predictors.Approximately 19% (30.7% males; 10.2% females) of adolescents currently smoke cigarettes, and 7% (8.5% males and 5.8% females) currently use non-cigarette tobacco products. Regardless of sex, peer smoking behavior was significantly associated with increased tobacco use among adolescents. In addition, exposures to tobacco industry promotions, secondhand smoke (SHS) and anti-smoking media messages were associated with tobacco use. The strong gender gap in the use of non-cigarette tobacco products, and the role of peer smoking and industry promotions in adolescent females’ tobacco use should be of major advocacy and policy concern. A comprehensive tobacco control program integrating parental and peer education, creating social norms, and ban on promotions is necessary to reduce adolescents’ tobacco use.

Tobacco in the 21st century.

1. Karen M. Wilson, MD, MPH* 1. *Children’s Hospital Colorado, University of Colorado School of Medicine and Dentistry, Aurora, CO. * Abbreviations: CEASE: : Clinical Effort Against Secondhand Smoke Exposure FDA: : Food and Drug Administration NRT: : nicotine replacement therapy SHS: : secondhand smoke SIDS: : sudden infant death syndrome Although there is increasing understanding that cigarette smoking and secondhand smoke exposure are significant health risks to children, adolescents continue to start smoking, and children are still exposed to secondhand smoke. To add to this, companies are finding more novel ways to market tobacco products, including electronic cigarettes and dissolvable tobacco products. Pediatricians should understand the consequences of tobacco smoke exposure and the use of emerging products and be able to screen and counsel families about their exposure. After completing this article, readers should be able to: 1. Identify the prevalence of secondhand smoke exposure among children in the United States. 2. Describe the health effects of cigarette smoking. 3. Understand the effects of secondhand smoke on children’s health and behavior. 4. Describe the role of the pediatrician in helping parents quit smoking and how to help parents access pharmacotherapy. 5. Understand the effect and use of noncigarette tobacco products. Eliza is a 5-year-old girl whose mother brings her to the office for wheezing. She has been coughing and having some upper respiratory tract congestion for 3 days, but this morning she developed increased wheezing and shortness of breath. Her mother has been giving her albuterol, which hasn’t seemed to help. She has a diagnosis of asthma and is taking an inhaled corticosteroid, which her mother says she has been using twice a day via a spacer, as directed at her last visit. Eliza was hospitalized at age 8 months with bronchiolitis, and since then she has been to the emergency department 6 times for exacerbations. She had to be hospitalized once but not in the intensive care unit. She has no other medical problems aside from …

Waterpipes and electronic cigarettes: increasing prevalence and expanding science.

The prevalence of noncigarette tobacco product use is on the rise across the globe, especially for waterpipes (also known as hookah, narghile, and shisha) and electronic cigarettes (e-cigarettes). The scientific literature reveals that waterpipe tobacco smoking is associated with exposure to a variety of toxicants that can cause short- and long-term adverse health events. In contrast, there is far less evidence of health harms related to e-cigarette use, although the variety of products in this category makes it difficult to generalize. We searched the PubMed database for all publications on waterpipes and e-cigarettes from January 2000 to March 2014. The number of publications on waterpipes rose in a slow, linear pattern during this time, while the number of publications on e-cigarettes showed exponential growth. The different trends suggest there may be more interest in studying a novel nicotine product (the e-cigarette) over a traditional tobacco product (the waterpipe). We posit that, although the specific research needs for these products are different, public health would be served best by a more equitable research approach. Scientists should continue to devote attention to understanding the unknown long-term health effects of e-cigarettes and their potential to serve as harm reduction or smoking cessation tools while simultaneously investigating how to reduce waterpipe smoking given that it exposes users to toxicants known to cause harm to health. Recent regulatory action in the United States, which proposes to include waterpipes and e-cigarettes under some of the same regulations as tobacco cigarettes, makes such research particularly timely.

Non-cigarette tobacco use among women and adverse pregnancy outcomes.

Although cigarette smoking remains the most prevalent form of tobacco use in girls and in women of reproductive age globally, use of non-cigarette forms of tobacco is prevalent or gaining in popularity in many parts of the world, especially in low- and middle-income countries. Sparse but growing evidence suggests that the use of some non-cigarette tobacco products during pregnancy increases the risk of adverse pregnancy outcomes. In this paper we review the literature on the prevalence of non-cigarette tobacco product use in pregnant women and in women of reproductive age in high-, middle-, and low-income countries and the evidence that maternal use of these products during pregnancy has adverse health effects. In addition, we communicate findings from an international group of perinatal and tobacco experts that was convened to establish research priorities concerning the use of non-cigarette tobacco products during pregnancy. The working group concluded that attempts to develop a public health response to non-cigarette tobacco use in women are hindered by a lack of data on the epidemiology of use in many parts of the world and by our limited understanding of the type and magnitude of the health effects of these products. We highlight research gaps and provide recommendations for a global research agenda.

Effect of different types of smoking and synergism with hepatitis C virus on risk of hepatocellular carcinoma in American men and women: case-control study.

The International Agency for Research on Cancer has declared smoking to be a risk factor for hepatocellular carcinoma (HCC). However, passive exposure to cigarette smoke and use of noncigarette tobacco products on the risk of HCC has not been examined. Therefore, we evaluated the independent effects of different types of smoking exposure along with multiple risk factors for HCC and determined whether the magnitude of smoking was modified by other risk factors in men and women. We conducted a case-control study at The University of Texas M. D. Anderson Cancer Center where 319 HCC patients and 1,061 healthy control subjects were personally interviewed for several HCC risk factors. Multivariate logistic regression analysis was performed to estimate the adjusted odds ratio (AOR) and 95% confidence interval (CI) for each potential risk factor. Use of smokeless tobacco (chewing tobacco and snuff), cigars, pipes and passive smoking exposure were not related to HCC among noncigarette smokers. However, regular cigarette smoking was associated with HCC in men: AOR, 1.9 (95% CI, 1.1-3.1). Heavy alcohol consumption was associated with HCC in women: AOR, 7.7 (95% CI, 2.3-25.1). Cigarette smoking interacted synergistically with chronic infection of hepatitis C virus in men: AOR, 136.3 (95% CI, 43.2-429.6) and with heavy alcohol consumption in women: AOR, 13.7 (95% CI, 3.2-57.9). We conclude that sex differences were observed in HCC relationship with cigarette smoking and alcohol consumption. Controlling for smoking exposure might be a prudent approach to the prevention of HCC, especially in patients with chronic viral hepatitis infections.

Reply to passive smoking and the use of noncigarette tobacco products in association with risk for pancreatic cancer

BACKGROUND—The associations between passive smoking and the use of noncigarette tobacco products with pancreatic cancer are not clear. METHODS—In this case-control study, the authors collected information on passive smoking and the use of noncigarette tobacco products in 808 patients with pancreatic adenocarcinoma and 808 healthy controls by personal interview. Multivariable logistic regression was performed to estimate the adjusted odds ratio (AOR) and 95% confidence interval (95% CI). RESULTS—The results confirmed the previously reported association between active smoking and increased risk for pancreatic cancer. The AOR was 1.7 (95% CI, 1.4-2.2) for regular smokers, 1.8 (95% CI, 1.4-2.4) for long-term smokers, and 3.1 (95% CI, 2.2-4.3) for former smokers. Although passive smoking showed a nonsignificantly elevated risk for pancreatic cancer in the entire study population (AOR, 1.3; 95% CI, 0.9-1.7), the association was present among ever smokers (AOR, 1.7; 95% CI, 1.03-2.6) but was absent among never smokers (AOR, 1.1; 95% CI, 0.8-1.6). Neither intensity nor duration of passive smoking modified the risk of pancreatic cancer among never smokers. The use of chewing tobacco, snuff, and pipes showed no significant risk elevation for pancreatic cancer after controlling for the confounding effects of demographics and other known risk factors. The use of cigars in never smokers showed a borderline significant increase of risk for pancreatic cancer (AOR, 2.2; 95% CI, 1.0-4.7; P =.05). CONCLUSIONS—The current observations did not support a role for passive smoking or the use of noncigarette tobacco products in the etiology of pancreatic cancer. The association between cigar use and the risk of pancreatic cancer needs to be confirmed in other study populations.

Passive smoking and the use of noncigarette tobacco products in association with risk for pancreatic cancer

W e read with interest the study by Hassan and colleagues that evaluated a possible association between passive smoking and pancreatic cancer. The authors report that passive smoking is not a significant risk factor for pancreatic cancer, although it may increase the risk in smokers who are also exposed to passive smoking. Although we congratulate the authors for their original research, we think that lack of data on the body mass index (BMI) among their considered confounding variables may somehow limit their conclusions. Indeed, although these authors claim that results were adjusted for ‘‘known risk factors,’’ no data on body weight are discussed. Although older articles, especially retrospective ones, have reached inconsistent results, obesity is a well recognized risk factor for pancreatic cancer, with a 12% increased risk per 5 kg/m BMI increase shown in a recent meta-analysis. The mechanisms by which obesity increases pancreatic cancer risk are unclear, but a role for the insulin-IGF axis is likely. Notably, in a cohort study on risk factors for pancreatic cancer, obese smokers had a relative risk of 5.07 compared with 2.39 for nonobese smokers and with 1.87 for obese nonsmokers, suggesting a possible additional effect of BMI, which may be important for passive smoking also. However, whereas the incidence of cancers mainly related to smoking, such as lung cancer, is overall decreasing in the US, possibly because of a reduction in smoking rates, that of pancreatic cancer is not. In conclusion, we believe that greater attention should be paid to avoiding possible biases when analyzing the role of potentially preventable risk factors for pancreatic cancer. Therefore, we believe that health policies aimed at reducing the increasingly high prevalence of obesity in western countries may be very important. Recognition of obesity as a risk factor provides further rationale for such policies, and, thus, it should be included in evaluation of risk factors for pancreatic cancer in the future.

Squamous cell carcinoma of the head and neck in never smoker–never drinkers: A descriptive epidemiologic study

While the attributed risk factors for the vast majority of patients with squamous cell carcinoma of the head and neck (SCCHN) are smoking and alcohol abuse, there appears to be a rising proportion of SCCHN patients who report no significant smoking or drinking history. This study reports the demographic and potential risk factors of a large series of never smoker-never drinker (NSND) patients. All subjects were participants in a prospective epidemiologic study of incident SCCHN. We obtained demographic data, clinical characteristics, and potential etiologic factors for 172 NSND patients and 1131 ever smoker-ever drinker (ESED) patients. RESULTS.: NSND patients were more likely to be female and to present at extremes of age, but overall were significantly younger than ESED patients. NSND patients had a higher proportion of oral cavity and oropharyngeal cancers than ESED patients had. Eleven percent of NSND patients (17% of NSND men) reported regular use of noncigarette tobacco products or marijuana, 41% (45% of NSND women) reported regular environmental exposure to tobacco smoke, 24% (36% of NSND men) reported regular occupational exposures to carcinogens/toxins, and 30% had a history of gastroesophageal reflux disease. More than half the NSND patients with an oropharyngeal primary were serologically positive for human papillomavirus type 16. NSND patients with SCCHN are commonly young women with oral tongue cancer, elderly women with gingival/buccal cancer, or young to middle-aged men with oropharyngeal cancer. While several exposures studied may be important to the etiology of a subset of these cancers in NSND patients, it is likely that no single known factor is responsible for a majority of SCCHN in NSNDs.