| While considerable information exists regarding the independent effects of caffeine and psychological stress on cardiovascular activity, there is relatively little information on their combined effects. Since caffeine may enhance cardiovascular responsivity to psychological stress, research on hemodynamic responses to caffeine-stress combinations may help elucidate mechanisms of hypertension development. In a series of studies, regular consumers of caffeine were exposed to laboratory and naturalistic stressors with and without prior caffeine intake. Among the findings were (1) caffeine and stress produced additive increases in blood pressure, (2) caffeine appears to potentiate beta-adrenergic responsivity to active coping, but not passive coping, stressors, (3) caffeine enhanced emotional responses to stress, and (4) cardiovascular responses to caffeine and stress in a naturalistic setting were similar to those observed in the laboratory. These results indicate that caffeine may enhance cardiovascular and psychological responses to stress, and that these responses may contribute to risk for essential hypertension. |
