Posted tagged ‘tobacco’

“A toxicological experiment:” Additional study needed on e-cigarettes use

April 12, 2018

Photo by Itay Kabalo

Although the market for e-cigarettes is booming, scientists and health agencies are still debating the extent of their health impacts. Basic questions remain: What chemicals are in the vapor cloud produced by e-cigarettes? And how does this vapor affect users and those around them?

A research team led by Hugo Destaillats, PhD, a chemist in the Indoor Environment Group at Lawrence Berkeley National Lab, is seeking the answers to these questions.

Destaillats and his colleagues have studied the complex chemical composition of vaping aerosols, the cloud of particles the devices emit. In one study, they quantified emissions from three e-liquids with various vaporizers, battery power settings and vaping habits — ranging from heavy to low puff duration and frequency.

The researchers found 31 potentially toxic substances in the vapors, including two not previously detected: propylene oxide in the e-liquids and glycidol in the vapors. Both of these compounds are considered probable carcinogens. They also determined that the base fluids used in vaping, propylene glycol and glycerin, can decompose when heated to produce acrolein, a powerful irritant.

However, the level of these toxins varied depending on the type of e-cigarette and how it was operated. For instance, toxic emissions rates were higher for e-cigarettes with a single heating coil compared to ones with double coils. Toxin levels also increased with the voltage used to power the device. And they rose with repeated use, presumably due to a buildup of residue within the device.

“We hope that one outcome of our research has been to provide useful information to manufacturers to help them improve the safety of their devices,” said Destaillats in a recent article in Analytical Scientist. .

In a follow-up study, the researchers assessed the health impact of firsthand and secondhand exposure to these vapor clouds under various typical use conditions. The integrated health damage from vaping for the various scenarios was lower than, or comparable to, the estimated damage from tobacco smoke, they concluded.

Given the countless unique e-liquid flavors and the on-going development of new devices, this research is difficult to generalize, they said, but they are concerned that more unidentified toxins exist.

Destaillats summarized in the article:

“Vaping is effectively a toxicological experiment being carried out with millions of people around the world.”

This is a reposting of my Scope blog story, courtesy of Stanford School of Medicine.

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Nicotine patches and medications aren’t enough to quit smoking, a study finds

December 26, 2017

I’ve watched family members and friends struggle to quit smoking, using nicotine patches and prescription medications. For many, it continues to be an ongoing battle.

This struggle is common, according to a new study from the University of California, San Diego that shows using smoking cessation drugs alone may not improve your chances of successfully quitting. The researchers studied two patient groups — comparing patients who used medication aids to ones that did not — to evaluate the effectiveness of three frontline smoking cessation drugs. To learn more, I spoke with the lead author Eric Leas, PhD, who conducted the research as a graduate student at UC San Diego and is now a postdoc at Stanford School of Medicine.

What inspired you to study the effectiveness of smoking cessation drugs?

“There is a major public health need for smoking cessation aids. Tobacco use remains the primary cause of cancer and cancer mortality in the United States and quitting smoking is so difficult for many smokers. I have several close family members and friends who have had debilitating disease caused by smoking and who struggled for many years to quit.

Several randomized trials have shown that some pharmaceutical smoking cessation aids can double quit rates. However, in the early 2000s, post-market surveillance studies of these cessation aids suggested that the population effectiveness did not match the randomized trial results. This was a major surprise to the medical field and met with some opposition. A criticism of these surveillance studies was that the same individual factors that make quitting difficult are also related to self-selected use of pharmaceutical aids when trying to quit. For instance, heavier smokers are more likely to use a cessation aid and also less likely to successfully quit. In social science and medicine this bias is known as ‘confounding.’”

Why did you study two “matched” patient groups?

“In our analysis, we attempted to address confounding variables using a method known as ‘matching.’ The goal of matching is to make study comparison groups similar with respect to potential confounders. In addition to cigarette consumption, we matched sociodemographics such as age, sex, race-ethnicity and education; smoking characteristics such as previous quit history and nicotine dependence; self-efficacy in quitting and having a smoke-free home.”

What did your study find?

“Even after matching, we found no evidence that the pharmaceutical aids improved the likelihood of successful quitting. While understandable, this finding is disappointing considering the need for successful cessation aids.

One possible explanation is that in many of the cessation randomized trials, smokers received the drugs in combination with intensive behavioral support. This support is not typically provided in the population. Prescribing behavioral support along with these drugs may be needed — as our results suggest that administering the drugs on their own is not working.”

What are you working on now?

“In collaboration with other professors at the School of Medicine and Stanford Business School, I am currently extending this work by studying how different groups of smokers respond to smoking cessation treatments, with the goal of developing tailored treatment plans.”

This is a reposting of my Scope blog story, courtesy of Stanford School of Medicine.

What you need to know about e-cigarettes

February 7, 2017

 

Photo by 1503849

Photo by 1503849

E-cigarettes are extremely popular with millions of middle and high school students across the United States. Kids love the flavors — like strawberry, bubble gum, chocolate cake and cotton candy — and blowing vapor into rings. And, they are inundated with ads that tout e-cigarettes as cool, harmless alternatives to cigarettes.

But, not surprisingly, e-cigarettes aren’t really safe. A recent University of California news story outlines ten important facts about e-cigarettes, including how they can harm your health.

One of the biggest health concerns is that e-cigarettes contain nicotine, which is addictive and can lead to the use of traditional cigarettes. “A lot of kids who take up [nicotine-free] vaping are at low risk for smoking, but once they start using e-cigarettes, they are three to four times more likely to start using cigarettes,” said Stanton Glantz, PhD, a tobacco researcher at the University of California, San Francisco, in the article.

In addition, e-cigarettes can contain other harmful ingredients, including:

  • Ultrafine particles that can trigger inflammatory problems and lead to heart and lung disease
  • Toxic flavorings that are linked to serious lung disease
  • Volatile organic compounds
  • Heavy metals, such as nickel, tin and lead

Stanford’s Bonnie Halpern-Felsher, PhD, a developmental psychologist who has studied tobacco use, also commented in the piece:

“Youth are definitely using e-cigarettes because they think they are cool… Adolescents and young adults don’t know a lot about e-cigarettes. They think it’s just water or water vapor. They don’t understand it’s an aerosol. They don’t understand that e-cigarettes can have nicotine. They don’t understand that flavorants themselves can be harmful.”

Furthermore, when e-cigarette users exhale the mainstream vapor containing these toxins, they can cause secondhand health effects.

The article discusses other hazards as well, including the possibility of battery explosion, and the products’ mixed record on helping smokers quit. It concluded with a call for more research to better understand the long-term health effects of e-cigarettes.

This is a reposting of my Scope blog story, courtesy of Stanford School of Medicine.

Quitting smoking: Best drug differs for men and women

July 22, 2016

It’s tough to quit smoking. I’ve seen friends and family members struggle with nicotine withdrawal symptoms: cravings for tobacco, anxiety, anger, irritation, increased hunger and even trouble thinking.

One out of six adults in the United States currently smoke and about half of them are trying to quit, but the success rate remains low. What’s the best way to stop smoking? A new study may help point the way — for women.

The study found that a medication frequently used to help smokers quit is more effective for women than men. Philip Smith, PhD, assistant medical professor at the City College of New York, led the multi-institutional study: a network meta-analysis of 28 randomized clinical trials involving a total of 14,389 smokers (51 percent female).

The researchers did a head-to-head comparison between the three common types of medications used for smoking cessation: the nicotine patch, varenicline (sold as Chantix and Champix) and sustained-release bupropion (sold as Wellburtin or Zyban). The quit rate of the participants was based on biochemical verification of their abstinence after six months.

The authors reported in their new paper in Nicotine & Tobacco Research:

“Women treated with varenicline were 41 percent more likely to achieve 6-month abstinence compared to women treated with TN [transdermal nicotine patch], and were 38 percent more likely to achieve 6-month abstinence than women treated with bupropion. For men, the benefit of varenicline over TN and bupropion were smaller and were not statistically significant.”

“Before our study, research had shown that among the choices for medications for smokers who wanted to quit, varenicline was the clear winner when it came to promoting quitting,” said Smith in a recent news release. “Our study shows this is clearly the case for women. The story seems less clear among men, who showed less of a difference when taking any of the three medications.”

The research findings identify varenicline as a particularly potent first option treatment for women. However, the good news for all smokers is that all three medicines significantly improved quit rates for both men and women, when compared with placebo.

If you’re trying to quit smoking, a combination of counseling and medication has been shown to be an effective way to treat tobacco dependence — speak with your doctor or contact a smoking cessation program.

This is a reposting of my Scope blog story, courtesy of Stanford School of Medicine.

Great American Smokeout: Time to Quit

November 21, 2013
photo of cigarette stubs in ashtray

Photograph courtesy of olumi_day via a Creative Commons license.

Smoking used to be portrayed as being glamorous in advertisements and movies. In old films, actors constantly smoked cigarettes and a tough guy usually had one hanging out the side of his mouth. It’s debatable whether smoking still makes you look cool though, especially since there are fewer and fewer public places you’re even allowed to smoke. Plus we now better understand the health risks of tobacco products.

Tobacco use is the single largest preventable cause of disease and premature death in the United States, but nearly 44 million Americans still smoke cigarettes – 1 in every 5 adults. There are also 14 million cigar smokers and 2 million pipe smokers.

Tobacco use is not quite as widespread in California, where just over 1 in every 7 adults smokes cigarettes. In the past year, 61 percent of these smokers attempted to quit.

There are many good reasons to quit smoking, and health concerns usually top the list. Half of all smokers who keep smoking die from a smoking-related illness, including lung cancer, other types of cancer, heart attack, stroke, or lung disease. Women who smoke are also more likely to miscarry or have a baby with a low birth-weight.

There are both immediate and long-term health benefits when smokers quit. After quitting for:

  • 20 minutes, your heart rate and blood pressure drop.
  • 12 hours, the carbon monoxide level in your blood drops to normal.
  • 2 weeks – 3 months, your circulation improves and lung function increases.
  • 1 – 9 months, your coughing and shortness of breath decrease.
  • 1 year, your risk of heart disease due to smoking cuts in half.
  • 5 years, your risk of various cancers (mouth, throat, esophagus, and bladder) is cut in half.
  • 15 years, your risk of heart disease is the same as a non-smoker.

Cigarettes are also expensive. You can use a savings calculator to see how much money you would save if you quit smoking. For example, a pack of cigarettes costs $6.77 on average in California. If you smoke a half pack (10 cigarettes) per day, this adds up $24 per week or $1220 per year.

Of course, the nicotine in tobacco is very addictive so quitting can be difficult, but the chance of success is increased with help. There are many treatment options used to help smokers quit and many of these treatments are covered by health insurance.

The most effective quitting method is a combination of counseling, social support and the use of cessation medication. The most common form of counseling is through telephone-quit lines, which provide free support and advice from an experienced cessation counselor. The counselor can provide a personalized quit plan, self-help materials, the latest information on cessation medications, and social support. For instance, 1-800-QUIT-NOW is a free national counseling service. Many clinics and hospitals also have counselors and support groups that you can meet with face-to-face. Counseling and support groups are also available online.

There are a variety of cessation medications that are available either over the counter or with a prescription. Nicotine replacement therapies deliver nicotine to help reduce the severity of nicotine withdrawal symptoms. The nicotine dose is gradually reduced over time. Nicotine gum, lozenges and patches can be purchased over the counter, whereas nicotine inhalers or nasal sprays require a doctor’s prescription.

Bupropioin SR (Wellbutrin or Zyban) is a non-nicotine prescription medication that acts on the chemicals in the brain that are related to nicotine craving. It can be used alone or with nicotine replacement products. Verenicline (Chantix) is a non-nicotine prescription medication that blocks the effects of nicotine, so it should not be used in combination with nicotine replacement products.

It is important for smokers to speak with their doctor and/or a cessation counselor to make a personalized quit plan that is right for them. And this week is a good time to get started, just in time to take part in the Great American Smokeout on November 21. Smokers across the nation will use this Thursday to make a quit plan, or plan in advance and quit smoking.

The Great American Smokeout happens every year on the third Thursday of November. It started in California back in 1976 when nearly 1 million smokers quit for the day, then the American Cancer Society expanded the program nationwide the following year. It has drawn attention to the deaths and chronic diseases caused by smoking, resulting in laws that ban smoking in restaurants and other public places.

The Great American Smokeout is celebrated with rallies, parades, stunts, quit programs, and “cold turkey” menu items. For instance, the community is invited to receive up-to-date cessation information, resources and giveaways at UCSF Medical Center’s Great American Smokeout event from 9-10 am and 12-1 pm on the Parnassus, Laurel Heights, Mission Bay and Mount Zion campuses. UC Berkeley is also celebrating the event with a “cold turkey” give-away – get a free cold turkey sandwich in exchange for a pack of cigarettes from 11 am – 2 pm at Sproul plaza.

This is a repost of my KQED Science blog.


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