Relatives of people with asthma are clinically healthy subjects with a genetically determined increased risk of developing asthma (see section 7.3 “Energy metabolism in Alzheimer’s disease”). In recent years, it has been shown that people genetically predisposed to asthma long, sometimes several decades before the onset of clinical symptoms, have certain biochemical and neurophysiological disorders associated with the subsequent development of the disease. Relatives of patients with asthma showed elevated plasma levels of abnormal neurotoxic beta-amyloid protein, whose deposits in the brain play a significant role in the formation of senile plaques (NR Graff-Radford et al., 1998). When performing mnestic tests, local cerebral blood flow in people genetically predisposed to asthma,increases in the hippocampus more significantly than normal (S. Bookheimer et al., 2000). In the study of visual evoked potentials (VEP) in relatives of patients with asthma, an increase in latent periods and amplitudes of late components is revealed, which indicates the likelihood of subclinical neurodegeneration and hyperactivation in polysynaptic reticulo-limbic-cortical pathways (N.V. Ponomareva et al. 1998). Bone-synchronous paroxysmal activity was found in the EEG during hyperventilation. SCP in this group is moderately elevated (N.V. Ponomareva et al., 1991, 1999).indicating the likelihood of subclinical neurodegeneration and hyperactivation in polysynaptic reticulo-limbic-cortical pathways (N.V. Ponomareva et al., 1998). Bone-synchronous paroxysmal activity was found in the EEG during hyperventilation. SCP in this group is moderately elevated (N.V. Ponomareva et al., 1991, 1999).indicating the likelihood of subclinical neurodegeneration and hyperactivation in polysynaptic reticulo-limbic-cortical pathways (N.V. Ponomareva et al., 1998). Bone-synchronous paroxysmal activity was found in the EEG during hyperventilation. SCP in this group is moderately elevated (N.V. Ponomareva et al., 1991, 1999).
The study of the correlation between the parameters of EEG and SCP, not only in norm, but also in relatives of patients with asthma allows us to consider their relationship in a wide range of variations.
At rest, the relatives of patients with asthma tended to increase in all SCP unipolar leads compared to the norm, the difference reached statistical significance level in the left temporal raids STI .
The parameters of the relative spectral power of the delta, theta, alpha and beta activity in relatives of patients with asthma at rest corresponded to the norm .
In the relatives examined by us, as well as in healthy ones, a positive correlation was observed at rest between SCP and the relative spectral power of alpha activity. The mean SCP correlated with the relative power of the alpha rhythm averaged over all leads ( r = 0.54; p = 0.048). In addition, the correlation was significant in the central region ( r = 0.56; p = 0.036), while in healthy subjects it was in the occipital.
The value of SCP in the frontal region was associated with a negative correlation with the relative spectral power of the delta activity in the same brain region ( r = -0.70; p = 0.005). SCP in the frontal region correlated with the average for all leads relative spectral power of the delta activity ( r = -0.64; p = 0.014). A similar correlation existed in the central region ( r = –0.56; p = 0.039) and in the right temporal region ( r = -0.54; p = 0.049). The average SCP was associated with the value of the average relative power delta ( r = –0.66; p = 0.01) (fig. 8.10). A similar pattern was observed in healthy subjects, but in the occipital region.
On the ordinate axis – the values of the averaged SCP, on the abscissa axis – the average for all leads relative spectral power of the delta activity
Thus, in relatives of patients with asthma in a state of calm wakefulness, there was a tendency to an increase in AMR in all areas, the differences reached a level of significance in the left temporal region. Such changes may be due to increased energy metabolism and a slight decrease in pH as a result of the stimulating neurotoxic effect of low concentrations of beta-amyloid protein found in the blood of relatives of patients for many years before the onset of the disease (NR Graff-Radford et al., 1999). However, at rest, the EEG parameters in them did not significantly differ from the norm. The relationship between EEG and SCP in this group was less, but on the whole it had a fundamental similarity with the correlation dependences found in the norm.