In a new study, parental smoking was linked to an elevated risk of children developing rheumatoid arthritis when they reach adulthood.
Drawing on data for 90 923 participants in the Nurses’ Health Study II (which included female registered nurses aged 25–42 years in 1989), the researchers found that 532 developed rheumatoid arthritis during a median follow-up of 27.7 years. Parental smoking when the participants were children was associated with a 75% higher risk of developing rheumatoid arthritis, even after controlling for personal smoking when the participants were adults. Among participants who went on to smoke as adults, this risk was even greater.
“These results suggest that early life inhalant exposures such as passive smoking may predispose individuals to develop rheumatoid arthritis later in life,” said senior author Jeffrey A. Sparks, MD, MMSc, of Brigham and Women’s Hospital.
“We used advanced statistical methods that allowed us to decipher the potential direct harm of early-life passive smoking experience on rheumatoid arthritis risk, while also taking into account factors occurring throughout adulthood,” added lead author Kazuki Yoshida, MD, ScD.
In addition to the well-documented risks of smoking and vaping, a new UCLA study has revealed that a short vaping session can affect the cells of even healthy younger nonsmokers.
According to their study, published in JAMA Pediatrics, a single 30-minute vaping session can significantly increase cellular oxidative stress, which occurs when the body has an imbalance between free radicals, and the antioxidants which neutralise them.
“Over time, this imbalance can play a significant role in causing certain illnesses, including cardiovascular, pulmonary and neurological diseases, as well as cancer,” said the study’s senior author, Dr Holly Middlekauff, a professor of cardiology and physiology at the David Geffen School of Medicine at UCLA.
E-cigarettes, devices that deliver nicotine with flavouring and other chemicals in a vapour rather than smoke, are popularly seen as a safer cigarette alternative, but research by Prof Middlekauff and others has demonstrated that vaping is associated with a number of adverse changes in the body that can presage future health problems.
For the present study, 32 male and female study participants, aged 21 to 33, were split into three groups: 11 nonsmokers, nine regular tobacco cigarette smokers and 12 regular e-cigarette smokers. The researchers collected immune cells from each individual before and after a 30-minute vaping session to measure and compare changes in oxidative stress among the groups.
The researchers repeated this with a control session where participants spent 30 minutes “sham-vaping,” or puffing on an empty straw.
In nonsmokers, oxidative stress levels were found to be two to four times higher after the vaping session than before. Among the regular cigarette and e-cigarette smokers, the same 30-minute exposure did not lead to an increase in oxidative stress, the researchers noted, most likely because their baseline levels of oxidative stress were already increased. “We were surprised by the gravity of the effect that one vaping session can have on healthy young people,” Prof Middlekauff said. “This brief vaping session was not dissimilar to what they may experience at a party, yet the effects were dramatic.”
The researchers noted that these results are especially troubling due to the increasing popularity of vaping, particularly among the youth. In a 2020 study, nearly a third of high school students reported e-cigarette use during the previous month.
There is still more to be understood about what exactly causes the changes in oxidative stress levels, whether it is caused by the nicotine or non-nicotine elements in e-cigarettes, which will be the subject of future research.
“While there’s a perception that e-cigarettes are safer than tobacco cigarettes, these findings show clearly and definitively that there is no safe level of vaping,” Prof Middlekauff said. “The results are clear, unambiguous and concerning.”
Giving the means to quit smoking to patients with depression could save as many as 125 000 lives over the next 80 years, researchers estimate. This number could be as high as 203 000 if people with depression who are not yet in mental health care settings are included.
The study, led by the Yale School of Public Health, shows the potential benefits that smoking cessation could have in a population suffering disproportionately from tobacco-related disease and death. Smokers with depression already find it harder to quit, and experience more negative withdrawal symptoms if they do, including increased depression. The study is also the first to estimate the population health effects of integrating smoking cessation treatments with standard mental health care. Using more than a decade of data from the National Survey on Drug Use and Health, the researchers made a model to project the effectiveness of smoking-cessation treatments into the future. They assessed how the benefits varied based on different rates of treatment adoption over the next 80 years.
Simulating the health benefits reveals that, at least 32 000 deaths could be prevented by 2100 if a significant number of patients with depression adopted any kind of cessation treatment. Assuming 100% mental health service utilisation and pharmacological cessation treatment, the number of potential lives saved could rise to 203 000.
“We’ve known for a long time that people with depression smoke more than the general population, and that mental health care settings often don’t have cessation treatment as part of standard care. Our study asks: what is that missed opportunity? What do we have to gain when mental health care and smoking cessation treatment are fully integrated,” said lead author and assistant professor Jamie Tam, PhD. The findings are published in the American Journal of Preventive Medicine.
Such high benefits would be a best-case scenario, the researchers cautioned. Even so, the model’s results match public health experts’ long-standing predictions of the results of smoking-cessation treatment becoming a routine part of mental health care. The findings show that even less-optimal cessation treatments would greatly impact both quality and length of life for patients living with depression.
“Beyond reducing the risk of early death, smoking cessation improves quality of life and increases productivity,” Tam added. “Decision makers should remove barriers to mental health care and smoking cessation treatments for people with mental health conditions.”
The researchers concluded that while existing treatments, such as nicotine replacement therapy, varenicline, and bupropion, can raise cessation rates by nearly 60%, in the future there would be even larger health gains if there were better cessation treatments.
A new study has developed a new model for examining the genetic risk for nicotine dependence.
Tobacco smoking carries undeniable health risks, and being unable to quit or moderate smoking draws out the problem. While some people may be casual smokers and can easily quit, others become heavy smokers who struggle to quit. This risk for nicotine dependence comes from a complex mix of environmental, behavioural, and genetic factors.
Twins studies indicate that 40 to 70 percent of the risk factors are heritable. Until recently, however, studies have only explained about 1 percent of the observed variation in liability to nicotine dependence, using a genetic score based on how many cigarettes a person smokes per day.
The new study led by psychologists at Emory University leveraged genome-wide association studies for a range of different traits and disorders correlated with nicotine dependence and explained 3.6 percent of the variation in nicotine dependence. The findings were reported in the journal Nicotine & Tobacco Research.
Higher polygenetic scores for a risk for schizophrenia, depression, neuroticism, self-reported risk-taking, a high body mass index, alcohol use disorder, along with more cigarettes smoked a day were all indicators of a higher risk for nicotine dependence, the researchers found. Meanwhile, the results showed that polygenetic scores associated with higher education attainment lowered the risk for nicotine dependence.
Senior author Rohan Palmer, assistant professor, Behavioral Genetics of Addiction Laboratory, Emory University explained: “If you look at the joint effect of all of these characteristics, our model accounts for nearly 4 percent of the variation in nicotine dependence, or nearly four times as much as what we learn when relying solely on a genetic index for the number of cigarettes someone smokes daily,”
“What we’re finding,” Prof Palmer added, “is that to better leverage genetic information, we need to go beyond individual human traits and disorders and think about how risk for different behaviors and traits are interrelated. This broader approach can give us a much better measure for whether someone is at risk for a mental disorder, such as nicotine dependence.”
“All of the traits and diseases we looked at are polygenic, involving multiple genes,” added first author Victoria Risner, who did the work as an Emory undergraduate majoring in neuroscience and behavioural biology. “That means that millions of genetic variants likely go into a complete picture for all of the heritable risks for nicotine dependence.”
The researchers hope that others will build on their multi-trait, polygenetic model and continue to boost the understanding of the risk for such complex disorders. “The more we learn, the closer we can get to one day having a genetic test that clinicians can use to inform their assessment of someone’s risk for nicotine dependence,” Prof Palmer said.
Though smoking hazards are well known, about 14 percent of Americans use tobacco daily. Around half a million people die each year in the US from smoking or exposure to smoke, and another 16 million have serious illnesses caused by tobacco use, including cancer, cardiovascular disease, and pulmonary disease. While chemicals produced during smoking and vaping cause the health impacts, nicotine hooks people on these habits.
Risner worked on this paper for her Honours thesis. “Nicotine dependence was interesting to me because the vaping scene was just arriving while I was an undergraduate,” she says. “I saw some of my own friends who were into vaping quickly becoming dependent on it, while some others who were using the same products didn’t. I was curious about the genetic underpinnings of this difference.” Risner is now in medical school at University of North Carolina.
The work made use of genome-wide association studies for a range of traits and disorders. The researchers then sought matching variants in genetic data from a nationally representative sample of Americans with nicotine dependence. Polygenetic scores for the different traits and disorders either raised or lowered the risk for that dependence. The strongest predictors were number of cigarettes smoked per day, self-perceived risk-taking, and educational attainment.
The multi-variant, polygenetic model offers a path forward. For instance, a clearer picture of heritability for nicotine dependence, may be gained by adding more risk associations to the model (such as nicotine metabolism) and clusters of polygenic traits (such as anxiety along with neuroticism).
“As we continue to zero in on who is most at risk for becoming nicotine dependent, and what inter-related factors, whether genetic or environmental, may raise their risk, that could help determine what intervention might work best for an individual,” Prof Palmer said.
“Just a few decades ago, it was not well understood that nicotine dependence could have a genetic component,” Risner said. “Genetic studies may help reduce some of the stigma society has against substance use disorders, while also making treatment more accessible.”
Journal information: Risner, V A., et al. (2021) Multi-Polygenic Analysis of Nicotine Dependence in Individuals of European Ancestry. Nicotine & Tobacco Research. doi.org/10.1093/ntr/ntab105.
A survey in the US has shown that cannabis users are often asthmatic, and some have allergies from cannabis smoking or its second-hand smoke.
Cannabis allergies can potentially cause respiratory symptoms, contact urticaria, angioedema, and uncommonly anaphylaxis. Inhalation of cannabis may also manifest in allergic rhinitis, conjunctivitis, wheezing, and throat oedema. Given the widespread legal use of cannabis, more information is needed on the effects of cannabis use, particularly smoking, on individuals with asthma and allergies.
The anonymous survey, conducted in concert with the Allergy & Asthma Network, consisted of 489 participants, 18% of whom reported cannabis use. A surprising 60% were asthmatic, and 40% had uncontrolled asthma.
Inhalation routes were the most popular way of taking cannabis. About half of users smoked cannabis, while a third vaped it. Only 40% reported being asked by their physician about cannabis use, and about the same proportion of participants were willing to talk to a physician about their cannabis use, said study co-author and cannabis allergy expert, William Silvers, MD.
“In order to more completely manage their allergy/asthma patients, allergists should increase their knowledge about cannabis and inquire about cannabis use including types of cannabinoid, route of use, reasons for use, and adverse effects,” said Dr Silvers. “As with cigarette smoking, efforts should be made to reduce smoking of cannabis, and recommend other potentially safer routes such as edibles and sublingual tinctures.”
Reported positive effects of cannabis use (eg, reduced pain, calm, improved sleep) were more frequent than adverse effects (eg, cough, increased appetite, anxiety). Approximately 20% of survey respondents reported coughing from cannabis, which was associated with smoking cannabis; this was cause for concern as it may indicate smoking risks for cannabis users.
“It surprised me that over half of the cannabis users in this study who have asthma were smoking it,” said principal investigator Joanna Zeiger, PhD. “And further, of those with uncontrolled asthma, half reported smoking cannabis. We also found that people with asthma are not routinely being asked or advised by their physician about cannabis and how they are consuming it.”
The researchers commented that further research into the relationship of cannabis and allergies is warranted. “We look forward to future studies of larger, more diverse cohorts to better explore more deeply the effect of cannabis use on asthma and other allergic disorders,” said Dr Zeiger.
Journal information: Zeiger, J. S., et al. (2021) Cannabis attitudes and patterns of use among followers of the Allergy & Asthma Network. Annals of Allergy, Asthma & Immunology.doi.org/10.1016/j.anai.2021.01.014.
