Cigarette smoking, psychological stress, and cardiovascular arousal

Both cigarette smoking and psychological stress, in the form of cognitive challenge imposed under laboratory conditions, reliably elevate cardiovascular arousal. This is typically transient; after a brief period of recovery, and in the absence of further challenge, cardiovascular arousal returns to some individual specific baseline. In those who are long-term smokers, or those who are subjected to chronic stressor exposure, however, elevated cardiovascular arousal may become permanent, and this has been hypothesised to mediate between smoking or stress (separately) and risk of cardiovascular disease. Of course, not all those who are either smokers or exposed to long-term stressors go on to develop cardiovascular disease. A decade ago, Dembroski and MacDougall (1986) suggested that smoking and stress may interact to produce a level of cardiovascular arousal that was greater than that arising from either in isolation. The present study examined the interaction of smoking and psychological stress (cognitive challenge) on cardiovascular arousal and found that a combination of smoking and stress did indeed elevate cardiovascular arousal to a degree greater than either one alone, and to a degree far greater than conditions of sham smoking or relaxation. This being so, it foreshadows an account of why exposure to particular cardiovascular risk factors (smoking and stress, in the case of the present study) do not explain greater variance in rates of cardiovascular disease inception.