Roughly 1 in 6 adults in the United States smoke. Females, compared to males, are less likely to quit smoking successfully and are at greater risk of developing smoking-related illnesses, like cardiovascular disease. Female smokers are also more likely to use cigarettes help cope with distressing emotions, like anxiety and depression, than male smokers. The difference can be partly attributed to biological sex differences. Estradiol and progesterone are two primary sex hormones that fluctuate throughout the female menstrual cycle. Estradiol and progesterone levels increase and decrease throughout the menstrual cycle, including during the “follicular phase” (estradiol is highest), ”early-middle luteal phase” (progesterone is highest), and “late-luteal phase” (rapidly declining progesterone and estradiol). Estradiol enhances the rewarding value of nicotine, including one’s desire for (“wanting”) cigarettes and degree of satisfaction after smoking, which can make it harder to quit smoking. Progesterone is associated with lower motivation for nicotine, thus might protect against smoking.
These sex hormones also play an important role in emotional functioning. High levels of progesterone can reduce anxiety and improve one’s ability to manage emotional distress. In contrast, when progesterone is rapidly declining during the late luteal phase, females report worsening of anxiety and distress and a reduced ability to cope with their emotions. Given that females often rely on cigarettes to cope with their emotions, we wanted to understand how these sex hormones influence emotional distress in female smokers. We hypothesized that females in the late-luteal phase would report higher levels of emotional distress compared to females in other menstrual phases. We also hypothesized that cigarettes would be more valuable among females in their follicular phase potentially due to estradiol’s effects on nicotine reward and elevated emotional distress in the preceding late-luteal phase.
We utilized data from 32 premenopausal female smokers who had normal menstrual cycles and were not on hormonal contraception. Participants were categorized as being in their follicular phase (n = 10), early-mid luteal phase (n = 15), or late-luteal phase (n = 7). The participants completed self-report measures of emotional distress and a task where they were given an opportunity to “purchase” hypothetical cigarettes, ranging from $0 (free) to $10 per cigarette. We found that females in the late-luteal phase reported higher levels of negative emotions, greater difficulties regulating their emotions and lower tolerance for emotional distress, compared to females in other phases. We also found that females in the follicular phase purchased an average of 19 cigarettes when cigarettes were free, and on average were willing to spend up to $9.00 on cigarettes. This purchasing behavior was higher than compared to females who were in their early-mid luteal or late-luteal phases, who purchased an average of 6 and 11 cigarettes, respectively, and on average were only willing to spend up $3 – $4 on cigarettes.
It is important to note that participants were assessed only once during their menstrual cycle, so this study could not test whether elevated emotional distress in the late-luteal phase causes elevated demand for cigarettes in the follicular phase. We also asked participants to self-report menstrual cycle status rather than directly measures levels of progesterone and estradiol. Our future research will build up on this study by directly measuring progesterone and estradiol in female smokers over the course of their menstrual cycle and evaluating how changes in these hormones influence emotional distress and the value of cigarettes. We believe that hormonal shifts throughout the menstrual cycle can create periods of time when females are at risk for experiencing emotional distress, which might contribute to continued motivation to smoke. This area of research will ultimately inform the development of highly personalized smoking cessation interventions that can be timed around a female’s menstrual cycle. We hope that future research will help us understand when to intervene during the menstrual cycle, what specific type of intervention is needed, and for whom specific intervention is most needed.
Read the full paper: Farris, S. G., Abrantes, A. M., & Zvolensky, M. J. (in press). Emotional distress and tobacco demand during the menstrual cycle in female smokers. Cognitive Behaviour Therapy. doi:10.1080/16506073.2018.1494208
Photo by: Julie Bocchino