Lung cancer mortality risk for U.S. menthol cigarette smokers

Lung cancer statistics, 2023

Despite decades of declining mortality rates, lung cancer remains the leading cause of cancer death in the United States. This article examines lung cancer incidence, stage at diagnosis, survival, and mortality using population-based data from the National Cancer Institute, the Centers for Disease Control and Prevention, and the North American Association of Central Cancer Registries. Over the past 5 years, declines in lung cancer mortality became considerably greater than declines in incidence among men (5.0% vs. 2.6% annually) and women (4.3% vs. 1.1% annually), reflecting absolute gains in 2-year relative survival of 1.4% annually. Improved outcomes likely reflect advances in treatment, increased access to care through the Patient Protection and Affordable Care Act, and earlier stage diagnosis; for example, compared with a 4.6% annual decrease for distant-stage disease incidence during 2013-2019, the rate for localized-stage disease rose by 3.6% annually. Localized disease incidence increased more steeply in states with the highest lung cancer screening prevalence (by 3%-5% annually) than in those with the lowest (by 1%-2% annually). Despite progress, disparities remain. For example, Native Americans have the highest incidence and the slowest decline (less than 1% annually among men and stagnant rates among women) of any group. In addition, mortality rates in Mississippi and Kentucky are two to three times higher than in most western states, largely because of elevated historic smoking prevalence that remains. Racial and geographic inequalities highlight longstanding opportunities for more concerted tobacco-control efforts targeted at high-risk populations, including improved access to smoking-cessation treatments and lung cancer screening, as well as state-of-the-art treatment.

Menthol: An underestimated anticancer agent

Menthol, a widely used natural, active compound, has recently been shown to have anticancer activity. Moreover, it has been found to have a promising future in the treatment of various solid tumors. Therefore, using literature from PubMed, EMBASE, Web of Science, Ovid, ScienceDirect, and China National Knowledge Infrastructure databases, the present study reviewed the anticancer activity of menthol and the underlying mechanism. Menthol has a good safety profile and exerts its anticancer activity via multiple pathways and targets. As a result, it has gained popularity for significantly inhibiting different types of cancer cells by various mechanisms such as induction of apoptosis, cell cycle arrest, disruption of tubulin polymerization, and inhibition of tumor angiogenesis. Owing to the excellent anticancer activity menthol has demonstrated, further research is warranted for developing it as a novel anticancer agent. However, there are limitations and gaps in the current research on menthol, and its antitumor mechanism has not been completely elucidated. It is expected that more basic experimental and clinical studies focusing on menthol and its derivatives will eventually help in its clinical application as a novel anticancer agent.

Comparison of Carcinogen Biomarkers in Smokers of Menthol and Nonmenthol Cigarettes: The 2015-2016 National Health and Nutrition Examination Survey Special Sample

BACKGROUND

The US FDA announced its commitment to prohibiting menthol as a characterizing flavor in tobacco. The relationship between cigarette menthol and exposure to toxic substances in mainstream tobacco smoke is not well characterized.

METHODS

Data from the National Health and Nutrition Examination Survey (NHANES) 2015 to 2016 special sample were used to study markers of 26 harmful and potentially harmful constituents (HPHC) in tobacco smoke. These include urine metabolites of polycyclic aromatic hydrocarbons (PAH), volatile organic compounds (VOC), and heavy metals in exclusive menthol (n = 162) and nonmenthol (n = 189) cigarette smokers. Urine metabolites of 7 PAHs, 15 VOCs, and 4 heavy metal biomarkers were compared by menthol status. Multivariable analyses were conducted on creatinine-adjusted concentrations.

RESULTS

There were no significant differences in cotinine levels or in 22 of 26 HPHCs. Among the urine metabolites of PAHs, the levels of 1-hydroxyphenanthrene were about 16% lower in menthol smokers. Among the urine metabolites of VOCs, menthol cigarette smokers presented significantly lower concentrations of acrylamide, N,N-dimethylformamide, and acrylonitrile. Menthol and nonmenthol smokers presented similar levels of heavy metals. Menthol did not affect the levels of cotinine and the nicotine metabolite ratio in urine.

CONCLUSIONS

Menthol and nonmenthol cigarettes deliver similar levels of most HPHCs.

IMPACT

Findings on toxicity are similar for menthol and nonmenthol cigarettes.

Smoking Quit Rates Among Menthol vs Non-Menthol Smokers: Implications Regarding a US Ban on the Sale of Menthol Cigarettes

BACKGROUND

A ban on the sale of menthol cigarettes in the United States is currently under consideration. A justification is that menthol cigarettes are harder to quit, particularly for African American smokers who use menthols much more frequently than White smokers, but epidemiologic data are limited.

METHODS

In a cohort of 16,425 mostly low income African American and White current cigarette smokers enrolled during 2002-2009, we computed smoking quit and re-uptake rates at three follow ups conducted means of 4.6, 7.7 and 11 years after entry. Generalized estimation equations were used to compute odds ratios (OR) and 95% confidence intervals (CI) for quitting and resuming smoking for menthol vs non-menthol smokers adjusted for race, age, education, income, and smoking pack years.

RESULTS

Crude annual quit rates among current smokers were 4.3% for menthol and 4.5% for non-menthol smokers, with adjusted ORs of quitting for menthol vs non-menthol smokers of 1.01 (95% CI = 0.91-1.11) overall, 0.99 (95% CI = 0.87-1.12) among African American and 1.02 (95% CI = 0.88-1.20) among White smokers. Crude annual smoking re-uptake rates were somewhat higher among menthol (8.4%) than non-menthol smokers (7.1%), with an adjusted OR of 1.19 (95% CI = 0.97-1.47), but net quit rates remained similar (OR = 1.01 [95% CI = 0.90-1.13] overall; OR = 1.00 [95% CI = 0.86-1.15] among African American participants; and OR = 1.04 [95% CI = 0.87-1.24] among White participants).

CONCLUSIONS

This large-scale prospective survey revealed similar quit rates among menthol and non-menthol smokers. Results contribute to policy discussions, especially if, as a meta analysis suggests, lung cancer risk is higher for non-menthol smokers and a ban leads menthol smokers to switch to non-menthol cigarettes.

Impact of Cigarette Filter Ventilation on U.S. Smokers' Perceptions and Biomarkers of Exposure and Potential Harm

BACKGROUND

Relationships between cigarette filter ventilation levels, biomarkers of exposure (BOE) and potential harm (BOPH), and harm perceptions were examined.

METHODS

Filter ventilation levels in cigarette brands were merged with Wave 1 (2013-2014) Population Assessment of Tobacco Use and Health study. Data were restricted to smokers who reported a usual brand and not regular users of other tobacco products. BOEs included nicotine, tobacco-specific nitrosamines, volatile organic compounds (VOC), and polycyclic aromatic hydrocarbons. BOPHs measured inflammation and oxidative stress. Perceived harm was assessed as self-reported risk of one's usual brand compared with other brands.

RESULTS

Filter ventilation ranged from 0.2% to 61.1% (n = 1,503). Adjusted relationships between filter ventilation and BOE or BOPH were nonsignificant except for VOC N-acetyl-S-(phenyl)-L-cysteine (PHMA) and high-sensitivity C-reactive protein (hsCRP). In pairwise comparisons, PHMA was higher in quartile (Q) 4 (4.23 vs. 3.36 pmol/mg; P = 0.0103) and Q3 (4.48 vs. 3.36 pmol/mg; P = 0.0038) versus Q1 of filter ventilation and hsCRP comparisons were nonsignificant. Adjusted odds of perceiving one's own brand as less harmful was 26.87 (95% confidence interval: 4.31-167.66), 12.55 (3.01-52.32), and 19.18 (3.87-95.02) times higher in the Q2, Q3, and Q4 of filter ventilation compared with Q1 (P = 0.0037).

CONCLUSIONS

Filter ventilation was not associated with BOE or BOPH, yet smokers of higher ventilated cigarettes perceived their brand as less harmful than other brands compared with smokers of lower ventilated cigarettes.

IMPACT

Research to understand the impact of this misperception is needed, and remedial strategies, potentially including a ban on filter ventilation, are recommended.

Measures of dependence in menthol and nonmenthol smokers - A comprehensive narrative review

Introduction. More than a decade ago, concerns were raised that menthol in cigarettes might enhance addiction to smoking. This article provides a comprehensive review of published studies examining cigarette dependence among menthol and nonmenthol smokers. The purpose of the review is to evaluate the scientific evidence to determine if menthol increases cigarette dependence. Materials and Methods. The published literature was searched in 2019 for studies that provide evidence on cigarette dependence among menthol compared to nonmenthol smokers. Included in this review are published studies that compare menthol and nonmenthol smokers based on widely accepted and validated measures of dependence, or other established predictors of dependence (age of smoking initiation [first cigarette]/age of progression [regular/daily smoking]) and indicators of dependence (smoking frequency, cigarettes smoked per day, time to first cigarette after waking, night waking to smoke, smoking duration). Results and Conclusion. Based on a review of the available studies, including those with adjusted results and large representative samples, reliable and consistent empirical evidence supports a conclusion that menthol smokers are not more dependent than nonmenthol smokers and thus menthol in cigarettes does not increase dependence.

Role of l- and d-Menthol in the Glucuronidation and Detoxification of the Major Lung Carcinogen, NNAL

Menthol, which creates mint flavor and scent, is often added to tobacco in both menthol and nonmenthol cigarettes. A potent tobacco carcinogen, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), is extensively metabolized to its equally carcinogenic metabolite 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) as (R)- or (S)-NNAL enantiomers. NNAL is detoxified by UDP-glucuronosyltransferase (UGT) enzymes, with glucuronidation occurring on either NNAL's pyridine ring nitrogen (NNAL-N-Gluc) or the chiral alcohol [(R)- or (S)-NNAL-O-Gluc]. To characterize a potential effect by menthol on NNAL glucuronidation, in vitro menthol glucuronidation assays and menthol inhibition of NNAL-Gluc formation assays were performed. Additionally, NNAL and menthol glucuronides (MG) were measured in the urine of smokers (n = 100) from the Southern Community Cohort Study. UGTs 1A9, 1A10, 2A1, 2A2, 2A3, 2B4, 2B7, and 2B17 all exhibited glucuronidating activity against both l- and d-menthol. In human liver microsomes, both l- and d-menthol inhibited the formation of each NNAL-Gluc, with a stereospecific difference observed between the formation of (R)-NNAL-O-Gluc and (S)-NNAL-O-Gluc in the presence of d-menthol but not l-menthol. With the exception of three nonmenthol cigarette smokers, urinary MG was detected in all menthol and nonmenthol smokers, with l-MG comprising >98% of total urinary MG. Levels of urinary NNAL-N-Gluc were significantly (P < 0.05) lower among subjects with high levels of total urinary MG; no significant changes in free NNAL were observed. These data suggest that the presence of menthol could lead to increases in alternative, activating metabolic pathways of NNAL in tobacco target tissues, increasing the opportunity for NNAL to damage DNA and lead to the development of tobacco-related cancers. SIGNIFICANCE STATEMENT: High levels of the major menthol metabolite, menthol-glucuronide, was observed in the urine of smokers of either menthol or nonmenthol cigarettes. The fact that a significant inverse correlation was observed between the levels of urinary menthol-glucuronide and NNAL-N-glucuronide, a major detoxification metabolite of the tobacco carcinogen, NNK, suggests that menthol may inhibit clearance of this important tobacco carcinogen.

Smokeless tobacco mortality risks: an analysis of two contemporary nationally representative longitudinal mortality studies

Background

Assessments supporting smokeless tobacco (SLT) disease risk are generally decades old. Newer epidemiological data may more accurately represent the health risks associated with contemporary US-based SLT products, many of which contain lower levels of hazardous and potentially hazardous chemicals compared to previously available SLT products.

Methods

Data from two longitudinal datasets (National Longitudinal Mortality Study—NLMS, and the National Health Interview Survey—NHIS) were analyzed to determine potential associations between SLT use and/or cigarette smoking and all-cause and disease-specific mortality. Mortality hazard ratios (HR) were estimated using a Cox proportional hazards regression model applied to various groups, including never users of any tobacco or SLT product, and current and former SLT users and/or cigarette smokers.

Results

The two datasets yielded consistent findings with similar patterns evident for the specific causes of death measured. All-cause mortality risk for exclusive SLT users was significantly lower than that observed for exclusive cigarette smokers and dual SLT/cigarette users. Similar trends were found for mortality from diseases of the heart, chronic lower respiratory diseases, and malignant neoplasms. Mortality risk for lung cancer in exclusive cigarette smokers was increased by about 12-fold over never-tobacco users but was rarely present in exclusive SLT users in either survey (NHIS, < 5 cases/1,563 observations; NLMS, 3 cases/1,863 observations). While the data in the surveys are limited, SLT use by former cigarette smokers was not associated with an increase in the lung cancer risk HR compared to that by former cigarette smokers who never used SLT.

Conclusions

Emerging epidemiological data provides a new perspective on the health risks of SLT use compared to risks associated with cigarette smoking. HR estimates derived from two current US datasets, which include data on contemporary tobacco products, demonstrate a clear mortality risk differential between modern SLT products and cigarettes. Cigarette smokers had an increased overall mortality risk and risk for several disease-specific causes of death, while SLT users consistently had lower mortality risks.

Electronic supplementary material

The online version of this article (10.1186/s12954-019-0294-6) contains supplementary material, which is available to authorized users.

Predictors, indicators, and validated measures of dependence in menthol smokers

This article presents a comprehensive review of the menthol cigarette dependence-related literature and results from an original analysis of the Total Exposure Study (TES), which included 1,100 menthol and 2,400 nonmenthol adult smokers. The substantial scientific evidence available related to age of first cigarette, age of regular use, single-item dependence indicators (smoking frequency, cigarettes per day, time to first cigarette, night waking to smoke), smoking duration, numerous validated and widely accepted measures of nicotine/cigarette dependence, and our analysis of the TES do not support that menthol smokers are more dependent than nonmenthol smokers or that menthol increases dependence.

The lingering question of menthol in cigarettes

Tobacco use is the single most important preventable cause of cancer-related deaths in the USA and many parts of the world. There is growing evidence that menthol cigarettes are starter tobacco products for children, adolescents, and young adults. Accumulating research also suggests that smoking menthol cigarettes reinforces nicotine dependence, impedes cessation, and promotes relapse. However, menthol cigarettes are exempt from the US Food and Drug Administration ban on flavored cigarettes due, in part, to the lack of empirical evidence describing the health consequences of smoking menthol cigarettes relative to regular cigarettes. Determining the biological effects of menthol cigarette smoke relative to regular cigarette smoke can clarify the health risks associated with the use of respective products and assist regulatory agencies in making scientifically based decisions on the development and evaluation of regulations on tobacco products to protect public health and to reduce tobacco use by minors. We highlight the inherent shortcomings of the conventional epidemiologic, clinical, and laboratory research on menthol cigarettes that have contributed to the ongoing debate on the public health impact of menthol in cigarettes. In addition, we provide perspectives on how future investigations exploiting state-of-the-art biomarkers of exposure and disease states can help answer the lingering question of menthol in cigarettes.

Smoking, menthol cigarettes and all-cause, cancer and cardiovascular mortality: evidence from the National Health and Nutrition Examination Survey (NHANES) and a meta-analysis

Background

The U.S. Food and Drug Administration has the authority to regulate tobacco product constituents, including menthol, if the scientific evidence indicates harm. Few studies, however, have evaluated the health effects of menthol cigarette use.

Objective

To investigate associations of cigarette smoking and menthol cigarette use with all-cause, cancer and cardiovascular risk in U.S. adults.

Methods

We studied 10,289 adults ≥ 20 years of age who participated in the National Health and Nutrition Examination Survey from 1999-2004 and were followed through December 2006. We also identified studies comparing risk of all-cause mortality, cardiovascular disease and cancer for menthol and nonmenthol cigarette smokers and estimates were pooled using random-effects models.

Results

Fifty-five percent of participants were never smokers compared to 23%, 17% and 5% of former, current nonmenthol and current menthol cigarette smokers, respectively. The adjusted hazard ratios (95% CI) for former, current nonmenthol and current menthol cigarette smokers compared to never smokers were 1.24 (0.96, 1.62), 2.40 (1.56, 3.71) and 2.07 (1.20, 3.58), respectively, for all-cause mortality; 0.92 (0.62, 1.37), 2.10 (1.02, 4.31) and 3.48 (1.52, 7.99) for cardiovascular mortality; and 1.91 (1.21, 3.00), 3.82 (2.19, 6.68) and 2.03 (1.00, 4.13) for cancer mortality. Using data from 3 studies of all-cause mortality, 5 of cardiovascular disease and 13 of cancer, the pooled relative risks (95% CI) comparing menthol cigarette smokers to nonmenthol cigarette smokers was 0.94 (0.85, 1.05) for all-cause mortality, 1.28 (0.91, 1.80) for cardiovascular disease and 0.84 (0.76, 0.92) for any cancer.

Conclusions

In a representative sample of U.S. adults, menthol cigarette smoking was associated with increased all-cause, cardiovascular and cancer mortality with no differences compared to nonmenthol cigarettes. In the systematic review, menthol cigarette use was associated with inverse risk of cancer compared to nonmenthol cigarette use with some evidence of an increased risk for cardiovascular disease.

Menthol cigarettes, race/ethnicity, and biomarkers of tobacco use in U.S. adults: the 1999-2010 National Health and Nutrition Examination Survey (NHANES)

BACKGROUND

In the United States, cigarette flavorings are banned, with the exception of menthol. The cooling effects of menthol could facilitate the absorption of tobacco toxicants. We examined levels of biomarkers of tobacco exposure among U.S. smokers of menthol and nonmenthol cigarettes.

METHODS

We studied 4,603 White, African-American, and Mexican-American current smokers 20 years of age or older who participated in the National Health and Nutrition Examination Survey (NHANES) from 1999 through 2010 and had data on cigarette type and serum cotinine, blood cadmium, and blood lead concentrations. Urinary total 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol) (NNAL) was studied in 1,607 participants with available measures.

RESULTS

A total of 3,210 (74.3%) participants smoked nonmenthol cigarettes compared with 1,393 (25.7%) participants who smoked menthol cigarettes. The geometric mean concentrations comparing smokers of nonmenthol with menthol cigarettes were 163.1 versus 175.9 ng/mL for serum cotinine; 0.95 versus 1.02 μg/L for blood cadmium; 1.87 versus 1.75 μg/dL for blood lead; and 0.27 versus 0.23 ng/mL for urine NNAL. After multivariable adjustment, the ratios [95% confidence interval (CI)] comparing smokers of menthol with nonmenthol cigarettes were 1.03 (0.95-1.11) for cotinine, 1.10 (1.04-1.16) for cadmium, 0.95 (0.90-1.01) for lead, and 0.81 (0.65-1.01) for NNAL.

CONCLUSIONS

In a representative sample of U.S. adult smokers, current menthol cigarette use was associated with increased concentration of blood cadmium, an established carcinogen and highly toxic metal, but not with other biomarkers.

IMPACT

These findings provide information regarding possible differences in exposure to toxic constituents among menthol cigarette smokers compared with nonmenthol cigarette smokers.

Smoking, menthol cigarettes, and peripheral artery disease in U.S. adults

INTRODUCTION

Cigarette flavorings, with the exception of menthol, have been banned in the United States under the Family Smoking Prevention and Tobacco Control Act. Given the large number of menthol cigarette smokers in the United States, we investigated whether cigarette type (nonmenthol or menthol) is associated with peripheral artery disease (PAD).

METHODS

The authors studied 5,973 adults, 40 years of age and older, who participated in the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2004. Smoking status and cigarette type were derived from self-reported questionnaires. PAD was defined as an ankle-brachial blood pressure index <0.9 in at least 1 leg.

RESULTS

Fifty percent of participants were never-smokers compared to 31%, 14%, and 5% of former, current nonmenthol, and current menthol cigarette smokers, respectively. The weighted prevalence of PAD in the study population was 5%. After multivariable adjustment, the odds ratios for PAD were 1.44 (95% CI: 0.97, 2.15), 3.65 (95% CI: 1.57, 8.50), and 2.51 (95% CI: 1.09, 5.80) comparing former, current nonmenthol cigarette smokers, and current menthol cigarette smokers to never-smokers. The associations between smoking and PAD were similar for smokers of nonmenthol and menthol cigarettes (p value for heterogeneity = .59).

CONCLUSIONS

In a representative sample of the U.S. population, current use of both menthol and nonmenthol cigarettes was associated with increased prevalence of PAD, with no difference in risk between cigarette types.