Some Possibillities for Stress Assessment in Large Groups.
S. Porta T, Gifford, J. Rand, D. Westmoreland
Institute of Applied Stress Research
Catecholamine, especially norepinephrine determination for the assessment of stress is the classic method, but the hormone has an exceptionally short half life and is expensive to determine. One needs skilled personnel and molesting blood sampling. We could show (Porta et al. 1997), that some effects of catecholamines, like changes in base excess, are linearly proportional to catecholamine levels, and therefore could be used as screening parameters. By measuring 10 different, stress related parameters, we may be able to get a whole pattern of the effects of stresses of different intensity and duration in the more or less immediate past, combinining the post stress provocation test (Porta et al. 1991) with the measurement of interrelated catecholamine effects, whose proportionalities may change according to the kind or severity of stresses, thus characterizing them.
Material and methods: Of 26 young volunteers on national service 50µl of capillary blood were taken just after light gymnastics and 3 minutes of jogging. Bicycle ergometry up to 200 watts (post stress provocation test, Porta et. al. 1993) was superimposed immediately, followed by a second blood sampling for determination of electrolytes, blood gases and lactate. A group of 20 more volunteers who did not undergo immediate previous stress, but sleep depriving night exercises followed by a field combat maneuver some hours beforehand, underwent the same procedure.
Most important results and conclusions: Ionized Mg was low in the first group and much higher in the second group, a feat not due to diet but to previous stress. Linear correlation between the parameters were the more plentiful, the higher the intensity of accumulated stress has been. Moreover, characteristic stress related interparameter correlation pattern (ICP) evolved, whereby Mg played an important role. Consequently, we formed 3 new subgroups, regardless of the previous workload, only characterized by the fact, of an increasing or decreasing or stable reaction of ionized Mg to the ergometric test. Average values, correlation numbers and ICPs pointed to the fact, that the increasing Mg group consisted mainly of subjects in a significant better bodily shape than in the decreasing group.