Personality traits and platelet monoamine oxidase in tobacco smokers.

A study was made of the smoking habits of an unselected series of 1129 18-year-old men from the general population. Their smoking habits were related to personality traits, intellectual level and platelet monoamine oxidase (MAO). Regular smokers were found to be extraverts, sensation seekers who were easily bored and with a strong tendency to avoid monotony. They also had a lower than average intellectual level, and were more prone to the abuse of alcohol, glue, cannabis, amphetamine and morphine. Furthermore, they had a low platelet MAO. The results are discussed in relation to the pharmacological reasons for smoking and favour the hypothesis that tobacco smoking is related to arousal-seeking behaviour. Ex-smokers had personality traits, intellectual levels and platelet MAO of the same magnitude as non-smokers: this may be the reason why they were able to give up smoking.