Sex differences in physiological response to the combination of stress and smoking

Abstract

Stressful situations are among the most commonly cited smoking triggers. Smoking and stress exposure each individually increase cardiovascular and hypothalamic-pituitary-adrenal measures with larger increases occurring when stress and smoking are combined. In this analysis, sex differences in the physiological response to the combination of stress and smoking are examined. Smokers (36 males; 34 females) completed a laboratory session in which systolic (SBP) and diastolic blood pressure (DBP), heart rate (HR), plasma epinephrine (Epi), norepinephrine and cortisol concentrations were measured at rest, while smoking a cigarette, during a speech task occurring immediately after smoking and at several time-points following the stressor. Significant period by sex effects were observed for HR, SBP, DBP and Epi but not for cortisol or norepinephrine concentrations. For SBP (p=0.002), the increase between resting and speech were larger in men than in women, primarily due to a larger increase between smoking and speech occurring in men. A similar pattern was observed for DBP and Epi with a significantly larger Epi increase from smoking to speech observed in men than in women (p=0.016). A different pattern emerged for HR - the total increase was larger in women (p<0.001), due to a larger rest to smoking increase (p<0.001). In most measures therefore, overall increases were greater in men than women, primarily due to larger smoking to speech increases. Additional research is needed to determine the clinical implications of these results as they apply to sex difference in smoking cessation success rates and in the cardiovascular risks of smoking.

Keywords: Blood pressure; Catecholamines; Heart rate; Mental stress; Sex differences; Smoking.

Figure

Systolic blood pressure (A), diastolic blood pressure (B), heart rate (C), plasma epinephrine concentrations (D), plasma norepinephrine concentrations (E), and plasma cortisol concentrations (F) (mean [standard error of the mean]) in participants who completed a laboratory session after receiving 4 weeks of placebo. p values are provided for the period within bracket (i.e. rest to smoking, smoking to speech and rest to speech). For Epinephrine, Norepinephrine and cortisol concentrations “Math+15” and “Math+30” refer to samples collected during a rest period at time-points corresponding to 15 minutes and 30 minutes following the conclusion of the math task