Overall, our findings suggest remarkable similarity in the pattern and heritability of nicotine withdrawal across young adult and adolescent smokers and across culture. More severe nicotine withdrawal was associated with all aspects of smoking cessation considered in the adults: difficulty quitting, persistent smoking, impairment following quitting, and seeking smoking cessation treatment, in addition to difficulty quitting and impairment in girls and boys, and seeking cessation treatment in the boys. Taken together, our results suggest that nicotine withdrawal plays an important role in psychiatric comorbidity and the process of smoking cessation in adult and adolescent smokers.
