Cardiovascular reactivity of different mental stress models in normotensives, borderline hypertensives and hypertensives

The present study compared simulated job-strain-conditions according to Karasek, in which psychological demand and decision latitude are independently varied (model I), with traditional concentration and short-term memory tasks (model II), with respect to their feasibility to differentiate cardiovascular reactivity in various blood pressure groups. Twenty normotensives, 20 borderline hypertensives and 20 untreated hypertensives (20–45 years) were investigated under both models in counterbalanced order. Each model consisted of a baseline, four mental tests separated by rest phases and a final recovery period. Blood pressure (BP) was recorded both intermittently from the brachial artery (Riva-Rocci) and continuously from the finger (Peñaz principle). Heart rate was also continuously recorded. The results show that model I evokes lower cardiovascular strain compared to model II, and that the expected cardiovascular effects can only be demonstrated for the peripheral BP in borderline hypertensives and hypertensives. Peripheral BP increases during the test phases of model I but decreases in model II. Cardiovascular reactivity does not significantly differ between the blood pressure groups. However, hypertensives show a significantly slower recovery in peripheral BP. With a reclassification rate of 70 percent over all conditions, the Karasek model does not give a more reliable discrimination of the blood pressure groups than model II. The usability of mental stress tests for identifying hypertension prone subjects is critically discussed.