Circulating leptin levels are associated with increased craving to smoke in abstinent smokers.

The adipocyte hormone leptin regulates satiety and energy expenditure. Recent evidence suggests that leptin is associated with increased craving for alcohol and with shorter length of abstinence during alcohol treatment. This study examined leptin's associations with craving for cigarettes and smoking relapse among smokers interested in cessation. Participants (32 smokers; 14 women) attended a laboratory session 24h following their designated quit day where circulating leptin levels and craving for smoking were assessed. Other measures of withdrawal symptoms, affect, physical symptoms, as well as neuroendocrine and cardiovascular measures were collected before and after performing two stress tasks (public speaking and cognitive tasks). High circulating leptin levels were associated with increased craving, withdrawal symptoms, negative affect, physical symptoms, and reduced positive affect. Circulating leptin levels were not related to cardiovascular and neuroendocrine measures, responses to acute stressors, or to smoking relapse. These results indicate that circulating leptin is a promising biological marker of craving for smoking and warrant further investigation of the links between appetite regulation and nicotine dependence.