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Smoking Can Increase Depressive Symptoms in Teens

　　While some teenagers may puff on cigarettes to "self-medicate" against the blues，scientists at the University of Toronto and the University of Montreal have found that smoking may actually -1- depressive symptoms in some teens.

　　"This observational study is one of the few to examine the perceived -2-benefits of smoking among teens," says lead researcher Michael Chaiton，a research associate at the Ontario Tobacco Research Unit of the University of Toronto．"-3- cigarettes may appear to have self-medicating -4- or to improve mood，in the long term we found that teens who started to smoke reported higher depressive symptoms."

　　As part of the study，some 662 high school teenagers completed up to 20 questionnaires -5- their use of cigarettes to affect mood．Secondary schools were selected to provide a mix of French and English participants，urban and rural schools，and schools -6- in high, moderate and low socioeconomic neighbourhoods．

　　Participants were divided into three -7-: never smokers；smokers who did not use cigarettes to self-medicate，improve mood or physical -8-；smokers who used cigarettes to self-medicate．Depressive symptoms were measured using a scale that asked how felt too fired to do things：had -9- going to sleep or staying -10-；felt unhappy，sad，or depressed；felt hopeless about the future；felt vexed，antsy or tense；and worried too much about things．

　　"Smokers who used cigarettes as mood -11- had higher risks of elevated depressive symptoms than teens who had never smoked," says co-researcher Jennifer 0'Loughlin，a professor at the University of Montreal Department of Social and Preventive Medicine．"0ur study found that teen smokers who reported emotional benefits from smoking are at higher risk of -12- depressive symptoms."

　　The -13- between depression and smoking exists -14- 一among teens that use cigarettes to feel better．"It's -15- to emphasize that depressive symptom scores were higher among teenagers who reported emotional benefits from smoking after they began to smoke," says Dr．Chaiton．

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