The pattern of the electrodermal activity as indicator of stress related reaction

The aim of the present study was to characterize the patterns of signals associated with noninvasively detected skin sudomotor transient reflexes in a group of 221 apparently healthy people, aged between 16 and 72 years. By means of two pairs of surface electrodes applied respectively to the palm of the hand and to the sole of the foot skin impedance changes were recorded as two electrodermal parameters: skin electrical resistance and skin electrical capacitance. The recordings were obtained under standard conditions initially in the basal resting state of the subject and then, after the application of some standardized stimuli (evoked electrodermal responses). In terms of the basal (spontaneous) electrodermal activity and the evoked responses the subjects were divided into three categories: I--those with a high threshold of sympathetic activation (quiet basal trace and ample evoked responses); II--those with a medium threshold for sympathetic activation (basal trace with some spontaneous electrodermal activity, but obviously of a lower amplitude than the evoked responses); III--those with a low threshold for sympathetic activation (a tracing showing frequent, larger spontaneous sympathetic discharges from which the evoked responses cannot be distinguished). Of the 221 subjects, 22.2% in group I, 69.2% were included in group II, and 8.6% in group III. Our data show that each individual presents a characteristic electrodermal pattern which expresses the degree of stability/instability of the sympathetic nervous system, the most sensitive component of the physiological stress reaction system.

Is microalbuminuria a different problem for type I and type II diabetes mellitus?

As in previous studies an improved single radial immunodiffusion technique was used for albumin, calculating the albumin/creatinine ratio in spot urine (mg/g/1.73 m2). This ratio was 4.7 +/- 0.0174 (geometric mean +/- SEM as logarithm) in 130 healthy controls, the highest value being 10.8. The 182 non-selected ambulatory diabetic patients presented three subgroups, each showing a non-gaussian frequency distribution: 47% with normal values (5.0 +/- 0.0224); 42% with ratio values from 11.0 to 88.8 (22.7 +/- 0.0269, significantly differing from the controls); 11% with clinical proteinuria (subsequently excluded from the study). Type I (9.6 +/- 0.0452; n = 76) and type II diabetic patients (10.7 +/- 0.0430; n = 86) significantly differed (p less than 0.001) from the controls but not from one another. Irrespective of the diabetes type, ratio values were significantly correlated with the duration of diabetes, age of patients, age of diagnosis (for instance 16.2 +/- 0.0974 in 15 patients aged greater than 65 years versus 9.1 +/- 0.0792 in 23 patients aged less than 20 years), glycemia level and chronic complications (especially retinopathy). Therefore, more than half the diabetic patients, non-selected, presented an increased albumin excretion as compared to the controls. On the other hand, microalbuminuria appears to be linked to age, duration of the disease and quality of the metabolic control rather than to the diabetes type.

Study of sodium and potassium intake in different categories of healthy subjects

The usual Na+ and K+ intake was investigated in 436 apparently healthy subjects, 370 men and 66 women, ranging in age from 19 to 56 years, distributed into three lots: 219 from a metallurgical plant, 100 from a military unit and 117 from an unselected population sample. The average Na+ intake amounted to 214 mEq/24 h in the first lot of study, to 224 mEq/24 h in the second and to 203 mEq/24 h in the third, the differences among them being not significant. K+ intake in the three lots was 38 mEq/24 h, 43 mEq/24 h and 49 mEq/24 h, respectively. Na+/K+ ratio reached 5.6 in lot I, 5.2 in lot II and 4.1 in lot III, compared to the unitary ratio in natural foodstuffs. The data obtained demonstrate that Na+ intake in the general population is excessive, while K+ intake is deficient. It is assumed that this might partly account for the great incidence of arterial hypertension.