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- Jern, Sverker, 1954, et al.
(författare)
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'Polycythaemia of stress' in subjects with Type A and Type B behaviour patterns.
- 1991
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Ingår i: Journal of psychosomatic research. - 0022-3999. ; 35:1, s. 91-8
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Tidskriftsartikel (refereegranskat)abstract
- To determine the importance of emotional stress for relative polycythaemia, we studied 11 subjects with the Type A and 11 subjects with the Type B behaviour patterns during short-term mental stress. All subjects were healthy, normotensive non-smoking young males aged 20-34 yr. without any medication. During rest there were no significant differences in heart rate, blood pressure, or plasma catecholamines between the two groups, but the A-group had significantly higher haemoglobin concentration (147 vs 140 g/l; p less than 0.005) and haematocrit (43.8 vs 42.1%: p = 0.05) than the B-group. In the whole group, there was a positive correlation between resting diastolic blood pressure and haemoglobin concentration (r = 0.53; p less than 0.05). In response to 10 min of mental arithmetic, haematocrit, haemoglobin and erythrocyte count rose approximately 2% (p less than 0.001 throughout). The stress-induced changes were not significantly different between the A- and B-groups. It is concluded that mild relative polycythaemia could be induced by acute emotional stress. In subjects with the Type A behaviour pattern a slight haemoconcentration is present already at rest, which further increases during stress.
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| 2. |
- Jern, Sverker, 1954, et al.
(författare)
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Short-term reproducibility of a mental arithmetic stress test.
- 1991
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Ingår i: Clinical science (London, England : 1979). - 0143-5221. ; 81:5, s. 593-601
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Tidskriftsartikel (refereegranskat)abstract
- 1. To evaluate the short-term reproducibility of heart rate, oscillometrically determined blood pressure, antecubital 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 (rs greater than 0.80 throughout) and as absolute reactivity measures (all rs greater than 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.
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