[Quantitative electroencephalography features and cognitive impairment in alcoholic patients]. / Características del electroencefalograma cuantitativo y trastornos cognitivos en pacientes alcohólicos.

AIM: To determine the exact relation between the characteristics of quantitative electroencephalogram analyses and the estimators of the cognitive status in alcoholic patients undergoing withdrawal. SUBJECTS AND METHODS: The study examined 49 patients diagnosed with alcoholism (DSM-IV) after 10 days of withdrawal, as well as the correlation between the bandwidth measures from the quantitative electroencephalogram (qEEG) analysis and the characteristics of the visual and auditory cognitive evoked potentials (P300) and from the findings of the attention and memory tests. RESULTS: The patients were divided into two groups: group one, which displayed an overall increase in the delta and theta absolute powers with frontal predominance, and group two, with reduced delta and theta absolute powers. Latency of the P300 wave was delayed in patients, particularly in those in group one, but regional absence of the P300 wave was more frequent in group two. Results of attention and memory tests were abnormal in patients, especially those in group one. CONCLUSIONS: The findings in the two groups appear to reflect different stages in the progression of alcoholism: the first only involved cortical dysfunction due to metabolic causes and the second possibly had added cortical atrophy. They might also represent two types of biological response by their nervous systems to the same pathogenic agent. These findings suggest that it is advisable to conduct follow-up studies involving qEEG, cognitive tests and magnetic resonance imaging of the brain in this kind of patient.

[Cognitive evoked potentials in uncomplicated hypertensive patients]. / Potenciales evocados cognitivos en pacientes con hipertensión arterial no complicada.

INTRODUCTION: One of the most frequent complications of vascular encephalopathies is the onset of cognitive disorders that lead the patient to a progressive decay of his abilities and useful life. Being high blood pressure (HBP) one of the most important causes of brain vascular disorders, we studied some aspects of cognition in HBP patients without neurological manifestations and with normal scores in Mini Mental State Examination. PATIENTS AND METHODS: There were studied 84 uncomplicated hypertensive patients, with a normal neurological physical examination and a group of 35 functionally healthy subjects. The patients were divided into three groups: slight high blood pressure (SLHBP, n = 24 age, 49 +/- 4) with diastolic blood pressure (DBP) between 90 and 100 mmHg, moderate high blood pressure (MHBP, n = 40, age 51 +/- 6) with DBP between 101 and 114 mmHg, and severe high blood pressure (SHBP, n = 20, age 49 +/- 8) with DBP of 115 mmHg or higher. All subjects underwent visual and auditory P300 evoked potentials. RESULTS: Visual and auditory P300 wave showed global latency delay, and amplitude decrease and absence of response in different leads, especially in frontal regions, higher in SHBP patients. This absence of response was more evident in auditory P300 in all patient groups. CONCLUSION: It is remarkable that neurologically asymptomatic HBP patients have P300 alterations with regional focalization, possibly due to a functional disorder related to hemodynamic changes in the central nervous system.