RESUMO
Altered amygdala activity in patients with schizophrenia can influence respiratory patterns and consequently cardiovascular parameters. Hence, we examined respiration and heart rate time series complexity as well as coupling of both signals. Electrocardiograms and respiratory signals were obtained from 25 unmedicated patients with schizophrenia and controls. Approximate entropy (ApEn) was calculated for heart and respiratory rates as well as cross-ApEn reflecting coupling of both signals. Coupling was decreased indicating diminished vagal modulation at the brain stem level. Regularity of breathing correlated with disease severity. These data might reflect a lack of inhibitory control over brainstem centers in schizophrenia.
Assuntos
Frequência Cardíaca/fisiologia , Mecânica Respiratória/fisiologia , Esquizofrenia/fisiopatologia , Adulto , Eletrocardiografia/métodos , Entropia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Dinâmica não Linear , Estatísticas não Paramétricas , Fatores de Tempo , Adulto JovemRESUMO
BACKGROUND: Depressed patients frequently complain about vegetative symptoms. The aim of the present study was to evaluate gastric electrical activity in patients suffering from major depression in relation to their symptoms. METHODS: Electrogastrography (EGG) was performed before and after a test meal ingestion in 21 patients suffering from major depression and control subjects. A structured interview was used to assess the severity of clinical as well as abdominal symptoms. RESULTS: Patients presented with significantly elevated proportions of tachygastria. Significant differences were found for the parameter arrhythmia, the coefficient of dominant frequency and slow wave after the test meal ingestion. A positive correlation was found between tachygastria and ANS score as well as tachygastria and the item "sweating". LIMITATIONS: Further studies are warranted to include more patients and to investigate interaction with specific antidepressive drugs. DISCUSSION: This is the first study demonstrating an increased amount of tachygastria in patients suffering from major depression which might be caused by increased sympathetic modulation. The correlation of tachygastria with the amount of gastric symptoms underlines the clinical significance of this finding.
