1. To evaluate the short-term reproducibility of heart rate, oscillometrically determined blood pressure, ante-cubital venous plasma catecholamine concentrations and subjective responses to strictly standardized mental arithmetic, we performed two identical tests 1 h apart in 14 young, healthy and normotensive male subjects (age 22–35 years) 2. Heart rate and blood pressure responses to the two stress tests were highly correlated, when expressed both as correlations between levels attained during stress ( r s >0.80 throughout) and as absolute reactivity measures (all r s >0.75). Also, subjective stress responses were highly correlated, when considering both levels during stress and reactivity ( r = 0.97 and r = 0.85, respectively). Stress levels of catecholamines were correlated, but the change scores (reactivity) were unrelated. 3. The measurement error sd for heart rate was 2.6 and 3.0 beats/min for reactivity and stress levels, respectively. The corresponding sd for blood pressure ranged between 2.7 and 4.4 mmHg. Subjective stress experience showed an sd of a similar magnitude. The responses of plasma catecholamine concentrations were subject to considerable variability. 4. It is concluded that haemodynamic and subjective stress responses and stress levels during the mental arithmetic stress test show acceptable reproducibility and high test-retest correlations. However, stress-induced changes in venous plasma catecholamine concentrations show low reproducibility.
1. The haemodynamic effects of hormonal changes during the menstrual cycle were examined in 11 normotensive women (age 20–46 years). The subjects were studied on days 2–8 (follicular phase) and days 18–26 (luteal phase) in a randomized order. A standardized mental stress test and a 24 h recording of ambulatory blood pressure and heart rate were performed. 2. Pre-stress resting levels of heart rate and blood pressure were similar during the two phases of the menstrual cycle. 3. During mental stress, the heart rate response was significantly greater during the luteal phase than during the follicular phase (14.7 versus 9.7 beats/min; P < 0.05). 4. Blood pressure, plasma catecholamine concentrations and subjective stress experience increased significantly in response to stress, without any significant differences between the two phases. 5. During 24 h ambulatory monitoring, higher levels of systolic blood pressure and heart rate were observed in the luteal phase than in the follicular phase ( P < 0.005 and P < 0.0001, respectively). 6. These data indicate that cyclic variations in female sex hormones not only affect systolic blood pressure and heart rate, but also alter the haemodynamic responses to psychosocial stress.