title: Cardiac autonomic function in chagasic elderly patients in an endemic area: A time and frequency domain analysis approach.
abstract: Chagas' disease is a common cause of cardiac autonomic impairment. In an endemic area there is a predominance of the indeterminate form and the number of elderly individuals committed by the disease is increasing. This study aimed to investigate the profile of heart rate variability (HRV) in elderly chagasic patients. 28 aged chagasic (CH), 28 non-chagasic (NC) aged individuals and 28 adults between 20 and 40 years old (YG) were studied. R-R intervals were assessed in time and frequency domains applying an autoregressive algorithm. There was no difference regarding temporal and spectral indices among the elderly groups in baseline. The values of the variance in CH, NC and YG individuals were 891.80, 283.60, 2557.00, showing a reduction of the total HRV in the aged groups when compared to the young control (p < 0.001). During the cold face test, the pNN50 response was significantly different only in the young group (p < 0.001). The temporal and spectral indices were not different among the elderly groups. The percentile changes of the R-R intervals induced by the tilt test in CH, NC and YG were respectively -7.04%, -9.35%, -15.81%, being significantly higher in the young individuals (p < 0.001). There was no difference regarding the percentile changes of the temporal and spectral indices between CH and NC elderly patients. The cardiac autonomic function assessed by HRV parameters presented no differences among the elderly individuals (CH and NC) living in an endemic area.
authors.affiliation: Division of Infectious Disease of Federal University of the Triângulo Mineiro, Uberaba, Minas Gerais State, Brazil.
authors.forename: Luiz Antônio Pertili Rodrigues
authors.initials: LA
authors.lastname: de Resende
authors.forename: Rodrigo Juliano
authors.initials: RJ
authors.lastname: Molina
authors.forename: Bruno Doriguetto Couto
authors.initials: BD
authors.lastname: Ferreira
authors.forename: Aldo César
authors.initials: AC
authors.lastname: Carneiro
authors.forename: Luiz Alberto Andrade
authors.initials: LA
authors.lastname: Ferreira
authors.forename: Valdo José Dias
authors.initials: VJ
authors.lastname: da Silva
authors.forename: Aluízio
authors.initials: A
authors.lastname: Prata
authors.forename: Dalmo
authors.initials: D
authors.lastname: Correia
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D000704:Analysis of Variance; D001341:Autonomic Nervous System / Q000503:physiopathology*; D001919:Bradycardia / Q000503:physiopathology; D002318:Cardiovascular Diseases / Q000453:epidemiology* / Q000209:etiology* / Q000473:pathology; D014355:Chagas Disease / Q000150:complications* / Q000453:epidemiology* / Q000473:pathology; D005260:Female; D015577:Geriatric Assessment; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D013610:Tachycardia / Q000503:physiopathology; D013997:Time Factors