Quitting Smoking May Help with Other Addictions
Several new studies link smoking to having other addictions, and even suggest that quitting smoking may decrease impulsive, risk-taking behaviors and emotional negativity, both of which increase the risk of addiction.
About 40% of smokers also abuse alcohol or drugs. A new study from the Ernest Gallo Clinic and Research Center at University of California, San Francisco, may provide some clues as to why.
Dr. Robert Messing and his colleagues isolated an enzyme in the brains of mice that plays a role in controlling the brain's response to both nicotine and alcohol. The research team genetically engineered mice to lack a gene for the protein kinase C (PKC) epsilon. These mice consumed less of nicotine-containing water than normal mice, and they were also less likely to return to an environment where they could obtain nicotine. In contrast, the normal mice in the study kept increasing their consumption of the nicotine solution.
"This could mean that these mice might not get the same sense of reward from nicotine or alcohol," said Dr. Messing. "The enzyme looks like it regulates the part of the reward system that involves nicotinic receptors."
Nicotine binds to nicotinic receptors on dopamine nerve cells, which causes dopamine to be released in the brain. Increased dopamine levels lead to a feeling of enjoyment and relaxation, and this in turn creates addiction.
The study appears in the Proceedings of the National Academy of Sciences.
Another study, this time from the Jonsson Comprehensive Cancer Center at the University of California, Los Angeles, found that smokers with comorbid disorders such as alcohol or drug addiction or mental health problems were five times more likely to quit if they received counseling from their family doctors compared to smokers with comorbid disorders who did not receive such counseling.
"In the context of everything physicians are trying to do in a day, smoking cessation may fall by the wayside," said Dr. Michael Ong, lead author. "It has been thought that with this patient population, you should take on only one thing at a time, for example, treating an opiate addiction and opting to deal with smoking cessation later. But at the end of the day we showed that smoking cessation counseling is effective in this patient population and should definitely be pursued."
The study appears in the journal Nicotine And Tobacco Research.
Finally, a study from the University of Missouri found that quitting smoking not only provides health benefits but also benefits the personality. Andrew Littlefield and his colleagues gave personality tests to smokers ages 18 to 35 and found that the smokers scored high on impulsivity, neuroticism and anxiety. Those who stopped smoking, however, lowered their scores.
"The data indicate that first-time young adult smoking is impulsive," said Littlefield. "That means 18-year-olds are acting without a lot of forethought and favor immediate rewards over long-term negative consequences. ... We find individuals who show the most decreases in impulsivity are also more likely to quit smoking. If we can target antismoking efforts on impulsivity, it may help people stop smoking."
As smokers get older, Littlefield said, smoking becomes an entrenched habit and not a matter of impulsivity.
The study appears in the journal Nicotine And Tobacco Research.
