People who smoke little or occasionally may have a severe nicotine addiction, a study by American scientists published in the American Journal of Preventive Medicine has found.
The new study shows that many light smokers, including those who don't smoke every day, may be addicted to cigarettes, said Jonathan Fowldes, a professor at Pennsylvania State University and co-author of the study.
To date, the common belief among doctors is that people who smoke less than 10 cigarettes a day are mildly addicted to nicotine.
Researchers included data from more than 6,700 smokers from the National Institutes of Health database in the study. All participants were fully screened for nicotine dependence (a tobacco use disorder) based on 11 diagnostic criteria.
The study authors found a definite nicotine dependence in 85% of the participants. About two-thirds of the people who smoked one to four cigarettes a day, and a quarter of those who did not smoke every day, were found to be addicted to nicotine.
Addiction severity (defined by the number of diagnostic criteria a person meets) was related to the number of cigarettes smoked. Moderate to severe addiction was found in 74% of people who smoked 21 cigarettes or more a day, and in 35% of those who smoked one to four cigarettes.
The authors noted that tobacco use disorder is more widespread than is commonly believed. Doctors often focus only on the number of cigarettes that patients smoke. Therefore, many people with nicotine addiction are overlooked by health care.
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