Of the estimated 42.1 million American adults that currently smoke cigarettes, around 40% try to quit an average of twice each year, but without success. Now, a new study published in JAMA suggests the use of medication could help smokers quit the habit gradually, resulting in better smoking cessation rates.
According to the Centers for Disease Control and Prevention (CDC), around 7 in 10 smokers in the US say they want to quit completely.
Current quit smoking guidelines from the US Department of Health and Human Services recommend that smokers give up the habit as quickly as possible by setting a quit date in the near future.
However, the researchers of this latest study - including Dr. Jon O. Ebbert of the Mayo Clinic - note that only 8% of smokers say they are ready to quit within the next month.
In addition, the team points to a telephone survey of more than 1,000 current daily cigarette smokers in the US, which revealed that around 44% would prefer to quit smoking through a steady reduction in the number of cigarettes smoked.
"Developing effective interventions to achieve tobacco abstinence through gradual reduction could engage more smokers in quitting," say the researchers.
As such, Dr. Ebbert and colleagues investigated the effectiveness of varenicline (brand name Chantix) - a medication used to treat nicotine addiction - in helping smokers reduce their cigarette use gradually, with the aim of making them quit for good.
Varenicline 'a useful treatment option for smokers who are unable to quit abruptly'
For their study, the team recruited 1,510 cigarette smokers from over 10 countries who were unwilling or unable to stop smoking within the next month, but who were willing to try and quit smoking within the next 3 months.
- Cigarette smoking is the leading preventable cause of death in the US, accounting for 1 in 5 deaths each year
- More than 16 million Americans are living with a smoking-related disease
- Quitting smoking significantly reduces the risk of a number of diseases, including heart disease, lung cancer and stroke.
The participants were randomly assigned to receive either 1 mg of varenicline or a placebo twice daily for 24 weeks. They were followed-up for 1 year.
At study baseline, the participants were given a target to reduce the number of cigarettes they smoked by at least 50% at 4 weeks and 75% at 8 weeks. At 12 weeks, they were told to make a quit attempt.
By week 4, the team found that 47.1% of participants who received varenicline had reduced the number of cigarettes smoked by at least 50%, compared with 31.1% of participants who received the placebo. At 8 weeks, 26.3% of those treated with varenicline reached the 75% cigarette reduction target, compared with 15.1% treated with the placebo.
When it came to quitting smoking, the researchers found that the participants treated with varenicline had much higher abstinence rates. At weeks 15-24, 32.1% of participants who received varenicline had ongoing smoking abstinence, compared with only 6.9% of those who received the placebo.
At weeks 21-24, continuous smoking abstinence rates for participants who received varenicline stood at 37.8%, compared with 12.5% who received the placebo, while at weeks 21-52, abstinence rates were 27% for the varenicline group and 9.9% for the placebo group.
The team notes that 3.7% of participants treated with varenicline experienced serious adverse events, compared with 2.2% of those treated with the placebo. In particular, the drug was linked to increased rates of constipation and weight gain, though the researchers note that these effects are also known to be caused by smoking cessation.
Overall, the researchers say their findings suggest varenicline may be an effective treatment option for smokers who are unable or unwilling to stop smoking quickly like the current US clinical guidelines recommend. They add:
"Because most clinicians are likely to see smokers at times when a quit date in the next month is not planned, the current study indicates that prescription of varenicline with a recommendation to reduce the number of cigarettes smoked per day with the eventual goal of quitting could be a useful therapeutic option for this population of smokers.
The approach of reduction with the goal of quitting increases the options for a clinician caring for a smoker."
The team says there were some limitations to their study. For example, they note that the participants received counseling via telephone or clinic visits. "Because of this, the observed abstinence rates with varenicline in actual clinical practice might be expected to be less than that observed in the current trial," they add.
Furthermore, they did not assess how the effectiveness of varenicline compares with other "reduce-to-quit" cessation treatments, such as nicotine replacement therapy.
The study was funded by pharmaceutical company Pfizer.
Last week, Medical News Today reported on a study published in the New England Journal of Medicine, which suggests current estimates about the number of people in the US who die from smoking are too low.