Cigarette smoking behaviors and the importance of ethnicity and genetic ancestry

Maternal smoking DNA methylation risk score associated with health outcomes in offspring of European and South Asian ancestry

Background

Maternal smoking has been linked to adverse health outcomes in newborns but the extent to which it impacts newborn health has not been quantified through an aggregated cord blood DNA methylation (DNAm) score. Here, we examine the feasibility of using cord blood DNAm scores leveraging large external studies as discovery samples to capture the epigenetic signature of maternal smoking and its influence on newborns in White European and South Asian populations.

Methods

We first examined the association between individual CpGs and cigarette smoking during pregnancy, and smoking exposure in two White European birth cohorts (n=744). Leveraging established CpGs for maternal smoking, we constructed a cord blood epigenetic score of maternal smoking that was validated in one of the European-origin cohorts (n=347). This score was then tested for association with smoking status, secondary smoking exposure during pregnancy, and health outcomes in offspring measured after birth in an independent White European (n=397) and a South Asian birth cohort (n=504).

Results

Several previously reported genes for maternal smoking were supported, with the strongest and most consistent association signal from the GFI1 gene (6 CpGs with p<5 × 10-5). The epigenetic maternal smoking score was strongly associated with smoking status during pregnancy (OR = 1.09 [1.07, 1.10], p=5.5 × 10-33) and more hours of self-reported smoking exposure per week (1.93 [1.27, 2.58], p=7.8 × 10-9) in White Europeans. However, it was not associated with self-reported exposure (p>0.05) among South Asians, likely due to a lack of smoking in this group. The same score was consistently associated with a smaller birth size (-0.37±0.12 cm, p=0.0023) in the South Asian cohort and a lower birth weight (-0.043±0.013 kg, p=0.0011) in the combined cohorts.

Conclusions

This cord blood epigenetic score can help identify babies exposed to maternal smoking and assess its long-term impact on growth. Notably, these results indicate a consistent association between the DNAm signature of maternal smoking and a small body size and low birth weight in newborns, in both White European mothers who exhibited some amount of smoking and in South Asian mothers who themselves were not active smokers.

Funding

This study was funded by the Canadian Institutes of Health Research Metabolomics Team Grant: MWG-146332.

Prevalence and Associated Factors Related to Tobacco Consumption Among University Students in Malaysia

Tobacco consumption is one of the major public health concerns worldwide. Moreover, alternative tobacco and nicotine products (ATNPs) are growing in popularity, especially among young adults in the past decade. The study aimed to determine the prevalence and associated sociodemographic factors of tobacco consumption among university students. A cross-sectional study was carried out among 338 university students of a private Malaysian university from March to April 2021. Data was collected using a self-administered online questionnaire with items including sociodemographic information, user status of tobacco consumption and types of tobacco product used. Descriptive statistics, Pearson's chi-square test, Fisher's exact test and simple and multiple logistic regression analyses were performed using the IBM SPSS version 26.0 to analyse the data. The prevalence of tobacco consumption in this study was 8.6% and the main tobacco product used was manufactured cigarettes. In Pearson's chi square test and Fisher's exact test, current use of tobacco was significantly associated with nationality, ethnicity, religion, school, current level of education and parents, siblings and friends use of tobacco (p<0.05). In simple and multiple logistic regression analysis, being non-Malaysian, Indian, Muslim, year 4 student and having parents or siblings who used tobacco, all had statistically significant associations with the current use of tobacco (p<0.05). Findings of this study showed that the use of tobacco among university students is concerning and warrants the need to develop and implement a strategic anti-tobacco program to limit this behaviour among university students.

Association between lifetime smoking and cutaneous squamous cell carcinoma: A 2-sample Mendelian randomization study

Background/Purpose

Cutaneous squamous cell carcinoma (cSCC) is one of the most common malignancies worldwide. While several environmental risk factors for cSCC are well established, there is conflicting evidence on cigarette smoking (and its potential causal effect) and cSCC risk. Furthermore, it is unclear if these potential associations represent causal, modifiable risk factors for cSCC development. This study aims to assess the nature of the associations between cigarette smoking traits (smoking initiation, amount smoked, and lifetime smoking exposure) and cSCC risk using two-sample Mendelian randomization analyses.

Methods

Genetic instruments, based on common genetic variants associated with cigarette smoking traits (P < 5 × 10-8), were derived from published genome-wide association studies (GWASs). For cSCC, we used GWAS summary statistics from the Kaiser Permanente GERA cohort (7701 cSCC cases and 60,167 controls; all non-Hispanic Whites).

Results

We found modest evidence that genetically determined lifetime smoking was associated with cSCC (inverse-variance weighted method: OR[95% CI] = 1.47[1.09-1.98]; P = .012), suggesting it may be a causal risk factor for cSCC. We did not detect any evidence of association between genetically determined smoking initiation or amount smoked and cSCC risk.

Conclusion

Study findings highlight the importance of smoking prevention and may support risk-stratified cSCC screening strategies based on carcinogen exposure and other genetic and clinical information.

Racial/Ethnic disparities in exposure to neighborhood violence and lung cancer risk in Chicago

BACKGROUND

Despite the lower prevalence and frequency of smoking, Black adults are disproportionately affected by lung cancer. Exposure to chronic stress generates heightened immune responses, which creates a cell environment conducive to lung cancer development. Residents in poor and segregated neighborhoods are exposed to increased neighborhood violence, and chronic exposure to violence may have downstream physiological stress responses, which may explain racial disparities in lung cancer in predominantly Black urban communities.

METHODS

We utilized retrospective electronic medical records of patients who underwent a screening or diagnostic test for lung cancer at an academic medical center in Chicago to examine the associations between lung cancer diagnosis and individual characteristics (age, gender, race/ethnicity, and smoking status) and neighborhood-level homicide rate. We then used a synthetic population to estimate the neighborhood-level lung cancer risk to understand spatial clusters of increased homicide rates and lung cancer risk.

RESULTS

Older age and former/current smoking status were associated with increased odds of lung cancer diagnosis. Hispanic patients were more likely than White patients to be diagnosed with lung cancer, but there was no statistical difference between Black and White patients in lung cancer diagnosis. The odds of being diagnosed with lung cancer were significantly higher for patients living in areas with the third and fourth quartiles of homicide rates compared to the second quartile of homicide rates. Furthermore, significant spatial clusters of increased lung cancer risk and homicide rates were observed on Chicago's South and West sides.

CONCLUSIONS

Neighborhood violence was associated with an increased risk of lung cancer. Black residents in Chicago are disproportionately exposed to neighborhood violence, which may partially explain the existing racial disparity in lung cancer. Incorporating neighborhood violence exposure into lung cancer risk models may help identify high-risk individuals who could benefit from lung cancer screening.

Risk profiles of adults with heavy alcohol use: Drinking patterns, behavioral and metabolic factors, health problems, and racial and ethnic disparities

BACKGROUND

Heavy alcohol use is a growing risk factor for chronic disease, yet little is known about its co-occurrence with other risk factors and health problems. This study aimed to identify risk profiles of adults with heavy alcohol use and examined potential disparities by race and ethnicity.

METHODS

This cross-sectional study included 211,333 adults with heavy alcohol use (in excess of daily or weekly limits recommended by National Institute on Alcohol Abuse and Alcoholism) between June 1, 2013 and December 31, 2014 in Kaiser Permanente Northern California. Latent class analysis was used to examine how heavy drinking patterns clustered with other behavioral and metabolic risk factors and health problems to form risk profiles. Multinomial logistic regression models were fit to examine associations between race, ethnicity, and risk profiles.

RESULTS

A 5-class model was selected as best fitting the data and representing clinically meaningful risk profiles: (1) "heavy daily drinking and lower health risks" (DAILY, 44.3%); (2) "substance use disorder and mental health disorder" (SUD/MH, 2.3%); (3) "heavy weekly drinking and lower health risks" (WEEKLY, 19.6%); (4) "heavy daily drinking and more health risks" (DAILY-R, 18.5%); (5) "heavy weekly drinking and more health risks" (WEEKLY-R, 15.3%). American Indian or Alaska Native (AIAN) and Black patients had higher odds than White patients of being in the SUD/MH, DAILY-R, and WEEKLY-R profiles than the DAILY profile. AIAN, Black, and Latino/Hispanic patients had higher odds than White patients of being in the SUD/MH, DAILY-R, and WEEKLY-R profiles rather than the WEEKLY profile.

CONCLUSIONS

AIAN, Black, and Latino/Hispanic patients with self-reported heavy drinking were more likely to be in risk profiles with greater alcohol consumption, more health risks, and higher morbidity. Targeted, culturally appropriate interventions for heavy alcohol use that may address other modifiable risk factors are needed to work towards health equity.

Risk factors for inguinal hernia repair among US adults

PURPOSE

To investigate demographic, clinical, and behavioral risk factors for undergoing inguinal hernia repair within a large and ethnically diverse cohort.

METHODS

We conducted a retrospective case-control study from 2007 to 2020 on 302,532 US individuals from a large, integrated healthcare delivery system with electronic health records, who participated in a survey of determinants of health. Participants without diagnosis or procedure record of an inguinal hernia at enrollment were included. We then assessed whether demographic (age, sex, race/ethnicity), clinical, and behavioral factors (obesity status, alcohol use, cigarette smoking and physical activity) were predictors of undergoing inguinal hernia repair using survival analyses. Risk factors showing statistical significance (P < 0.05) in the univariate models were added to a multivariate model.

RESULTS

We identified 7314 patients who underwent inguinal hernia repair over the study period, with a higher incidence in men (6.31%) compared to women (0.53%). In a multivariate model, a higher incidence of inguinal hernia repair was associated with non-Hispanic white race/ethnicity, older age, male sex (aHR = 13.55 [95% confidence interval 12.70-14.50]), and more vigorous physical activity (aHR = 1.24 [0.045]), and alcohol drinker status (aHR = 1.05 [1.00-1.11]); while African-American (aHR = 0.69 [0.59-0.79]), Hispanic/Latino (aHR = 0.84 [0.75-0.91]), and Asian (aHR = 0.35 [0.31-0.39]) race/ethnicity, obesity (aHR = 0.33 [0.31-0.36]) and overweight (aHR = 0.71 [0.67-0.75]) were associated with a lower incidence. The use of cigarette was significantly associated with a higher incidence of inguinal hernia repair in women (aHR 1.23 [1.09-1.40]), but not in men (aHR 0.96 [0.91-1.02]).

CONCLUSION

Inguinal hernia repair is positively associated with non-Hispanic white race/ethnicity, older age, male sex, increased physical activity, alcohol consumption and tobacco use (only in women); while negatively associated with obesity and overweight status. Findings from this large and ethnically diverse study may support future prediction tools to identify patients at high risk of this surgery.

Tobacco Consumption Among Young Population in Rural Indonesia: Prevalence and Associated Factors

Introduction: Tobacco consumption among youths is increasing in Indonesia and other middle-income countries. In rural areas, its prevalence is even higher compared to urban settings. Understanding the extent and associated factors of tobacco consumption within this population is essential to inform the formulation of appropriate prevention and control strategies. Aims: This study aims at analyzing the prevalence and associated factors of tobacco consumption among the young population living in rural Indonesia. Methods: Data were obtained from Indonesia Family Life Survey wave 5 (IFLS-5). A total of 2,786 responses from respondents aged 15-24 years and living in rural areas were taken into analysis. Binary logistic regression was used to examine the association between tobacco consumption with the predictors. Results: The prevalence of tobacco consumption among youths in rural Indonesia was 26.5%. Binary logistic regression discovered that factors significantly associated with tobacco consumption among young population were aged 20-24 years (AOR = 4.760, 95% CI: 3.557-6.368), less educated (AOR = 5.988, 95% CI: 3.193-11.229), being married (AOR = 2.484, 95% CI: 1.631- 3.782), and having smoking parent (AOR = 1.346, 95% CI: 1.016-1.783). Young males had a much higher tobacco use prevalence (57.1%). Whereas females had significant negative association with tobacco consumption (AOR = 0.001, 95% CI: 0.000-0.002). Conclusion: A large portion of youth in rural Indonesia were identified to have tobacco-use behavior. Appropriate prevention and control strategies are needed to address the population groups identified in this study. Policymakers should anticipate challenges that may occur resulting from geographical and cultural differences.