Sex- and race-related differences among smokers using a national helpline are not explained by socioeconomic status

Sex differences in resting state brain function of cigarette smokers and links to nicotine dependence

Sex--a marker of biological and social individual differences--matters for drug use, particularly for cigarette smoking, which is the leading cause of preventable death in the United States. More men than women smoke, but women are less likely than men to quit. Resting state brain function, or intrinsic brain activity that occurs in the absence of a goal-directed task, is important for understanding cigarette smoking, as it has been shown to differentiate between smokers and nonsmokers. But, it is unclear whether and how sex influences the link between resting state brain function and smoking behavior. In this study, the authors demonstrate that sex is indeed associated with resting state connectivity in cigarette smokers, and that sex moderates the link between resting state connectivity and self-reported nicotine dependence. Using functional MRI and behavioral data from 50 adult daily smokers (23 women), the authors found that women had greater connectivity than men within the default mode network, and that increased connectivity within the reward network was related to increased nicotine tolerance in women but to decreased nicotine tolerance in men. Findings highlight the importance of sex-related individual differences reflected in resting state connectivity for understanding the etiology and treatment of substance use problems.

Smoking and white matter hyperintensity progression: the ARIC-MRI Study

OBJECTIVE

Our objective was to examine the link between smoking and smoking history, including smoking intensity and cessation, overall and by race, in a biracial prospective cohort study.

METHODS

A subset of Atherosclerosis Risk in Communities Study participants (n = 972, 49% black) completed brain MRI scans twice (1993-1995 and 2004-2006). We defined white matter hyperintensity (WMH) progression as an increase of ≥2 points on the 9-point Cardiovascular Health Study scale across scans. Participants reported information on smoking behavior at the baseline MRI and at 2 prior study visits, approximately 3 and 6 years before baseline. We used adjusted logistic regression to evaluate the association between smoking variables and WMH progression in the total sample and separately by race (black and white).

RESULTS

We found WMH progression in 23% of participants (30% of black participants, 17% of white participants). Overall, being a current smoker 6 years before baseline was associated with WMH progression. In race-stratified analyses, we found adverse associations with smoking status at multiple time points and persistent smoking in white but not in black participants. However, we found no statistical support for effect modification by race for most of these analyses. Increasing pack-years of smoking was associated with greater risk of WMH progression, while time since quitting and age at smoking initiation were not associated with WMH progression, with little indication of differences in these associations by race.

CONCLUSIONS

Our findings concur with previous studies suggesting a relationship between smoking and WMH progression, and further demonstrate a dose-dependent association.

Racial, Ethnic, and Language Disparities in Children's Exposure to Secondhand Smoke

Race and ethnicity affect children's risk of secondhand smoke exposure. However, little is known about how race and language preference impact parents' self-reported smoking and stopping smoking rates. We analyzed data for 16,523 children aged 0-11 years from a pediatric computer decision support system (Child Health Improvement through Computer Automation [CHICA]). CHICA asks families in the waiting room about household smokers. We examined associations between race, insurance, language preference, and household smoking and reported stopping smoking rates using logistic regression. Almost a quarter (23%) of the children's families reported a smoker at home. Hispanic children are least likely (odds ratio [OR]: 0.17, confidence interval [CI]: 0.12-0.24) to have secondhand smoke exposure when compared to African American and white children, as were those with private insurance (OR: 0.52, CI: 0.43-0.64) or no insurance (OR: 0.79, CI: 0.71-0.88) compared to publicly insured. Children from English speaking families were more likely (OR: 1.55, CI: 1.24-1.95) to have secondhand smoke exposure compared to Spanish speaking families. Among smoking families, 30% reported stopping smoking subsequently. Stopping rates were higher in Hispanic (OR: 3.25, CI: 2.06-5.13) and African American (OR: 1.39, CI: 1.01-1.91) families compared to white children's families. Uninsured families were less likely than publicly insured families to report stopping smoking (OR: 0.76, CI: 0.63-0.92). English speaking families were less likely (OR: 0.56, CI: 0.41-0.75) to report stopping smoking compared to Spanish speaking even in a subgroup analyses of Hispanic families (OR: 0.55, CI: 0.39-0.76). In our safety net practices serving children predominantly on public insurance, Spanish speaking families reported the lowest risk of secondhand smoke exposure in children and the highest rate of stopping smoking in the household. Hispanic families may have increasing secondhand exposure and decreasing rates of stopping smoking as they acculturate.