Researchers at Penn State School of Medicine and Harvard Medical School say that reducing the nicotine content in cigarettes to non-addictive levels can reduce smoking
without worsening the mental health of smokers with mood or anxiety disorders.
They say reducing the amount of nicotine in cigarettes can also reduce addiction, reduce exposure to toxic substances and increase smokers' chances of
In the United States, tobacco remains the leading preventable cause of
premature death and disease.
Food and Drug Administration (FDA) and the New Zealand government recently proposed limiting the amount of nicotine in cigarettes to the lowest levels
that are addictive.
Previous research has shown that reducing nicotine levels can help smokers quit, but there is little evidence on whether these policies adversely affect current or previous smokers with emotional disorders such as depression and anxiety — conditions that are estimated to be 38 percent of smokers in the United States
Jonathan Foulds, a professor of public health sciences, psychiatry and behavioral health, said smokers with mental health problems were more likely to experience severe nicotine withdrawal symptoms and had a lower
success rate of quitting.
He also said there has been speculation that reducing nicotine levels to very low levels could worsen psychiatric symptoms in smokers with mental health problems, leading to more smoking and increasing exposure to
toxic substances or harmful chemicals.
Researchers studied 188 smokers who either had a history of mood or anxiety disorders or did not currently have a plan to quit smoking
Volunteers were randomly assigned to receive study cigarettes containing normal nicotine content (11.
6 mg nicotine per cigarette) and another group receiving cigarettes with gradually reduced nicotine content (the final nicotine content was 0.
2 mg nicotine per cigarette) for 18 weeks
At the beginning and end of the study, the researchers measured levels of cotinine (a metabolite of nicotine), levels of harmful chemicals, cigarette dependence index, and various mental health indicators
The researchers observed no statistically significant difference
in mental health measures between the two groups at the end of the study.
The team used the Kessler Psychological Distress Scale, a six-self-reported assessment in which participants reported on a 5-point scale the degree of feeling or emotion they experienced, such as "nervousness," "hopelessness," or "depression to the point that nothing would cheer them up
" The score is obtained by summing the points of the six experiences
Participants in the nicotine reduction group scored an average of 5.
3 points at the start of the study and an average final score of 4.
6 points, while participants in the normal nicotine group scored an average of 6.
1 points at the start of the study and a final score of about 4.
Foulds, a researcher at the Cancer Institute at Pennsylvania State University, said: "These findings are important because we want to understand the impact
of these policies on smokers with anxiety or depressive disorders.
" "Our data show no significant differences in mental health measures between the two groups, suggesting that reducing nicotine cigarettes may not have adverse psychological effects
in this population.
Similar to previous studies, Foulds and his team found that the group in the nicotine reduction group absorbed lower amounts of nicotine and ingested lower levels of harmful carcinogens, such as the biomarker 4-(methylnitrosamine)-1-(3-propyl)-1-butanol, commonly referred to as NNAL.
At the end of the randomized phase of the trial, this group also smoked fewer cigarettes and reported lower
levels of nicotine addiction.
The findings were published Nov.
the journal PLoS Synthesis.
The study was unique in that after 18 weeks, both groups of participants had the option to "choose their treatment.
They can reuse their cigarettes, continue smoking research cigarettes, or try to quit
Of the 188 participants in the study, those who randomly selected cigarettes with lower nicotine content were more likely to quit after 12 weeks (18.
1 percent), compared with those in the control group (usually nicotine content) (4.
"We believe this is the first randomized trial to find that smokers who use cigarettes with very low nicotine content are more likely to quit (biochemically verified)
three months after the end of the trial," Foulds said.
"Our findings suggest that these policies may reduce nicotine absorption from cigarettes without worsening the mental health of smokers with mood or anxiety disorders," said
Eden Evans, professor of family psychiatry at Cox at Harvard Medical School.
"They also show that smokers with mood and anxiety disorders can successfully quit smoking through these policies
with the right support and resources.