Cardiovascular variability (CVV) has been evaluated in patients with Parkinson's disease (PD) in other countries and exhibit ethnic differences. Objective: We investigated heart rate variability (HRV) and blood pressure variability (BPV) in Mexican patients with PD. Method: We further compared HRV and BPV between this group and young healthy controls (YHC) in order to estimate, for the first time in our country, the magnitude of the difference. Twenty patients were examined. Time-and frequency-domain CVV parameters were studied during supine rest (SR), active standing (AS) and controlled breathing. These measurements were compared to those of 20 YHC. Results: In the three conditions tested, our study showed a decrease in almost all HRV parameters in PD patients; on the contrary, decreased BPV parameters were found less frequently and only during SR and AS. Conclusion: Our results indicate that HRV is impaired in PD. Some BPV parameters are also diminished.Keywords: Parkinson's disease, autonomic nervous system, heart rate variability, blood pressure variability, dysautonomia.
RESUMOA variabilidade cardiovascular (VCV) tem sido avaliada em doentes parkinsonianos em vários países e apresenta diferenças étnicas. Objetivo: Investigar a variabilidade da frequência cardíaca (VFC) e a variabilidade da pressão arterial (VPA) em doentes parkinsonianos mexicanos. Método: Comparamos VFC e VPA entre o grupo de estudo e controles jovens (CJ), a fim de estimar a magnitude da diferença. CVV foi estudada no domínio do tempo e da frequência durante repouso supino (RS), ortostase ativa (OA) e respiração controlada. Estas medições foram comparadas com aquelas de 20 CJ. Resultados: Nosso estudo mostrou diminuição em quase todos os parâmetros da VFC em doentes parkinsonianos. A diminuição dos parâmetros da VPA foi encontrada com menos frequência. Conclusão: Nossos resultados indicam que a VFC é prejudicada na doença de Parkinson. Alguns parâmetros do VPA também são reduzidos.Palavras-chave: doença de Parkinson, sistema nervoso autônomo, variabilidade da frequência cardíaca, variabilidade da pressão arterial, disreflexia autonômica.The clinical features of Parkinson's disease (PD) are not restricted to the classical triad of resting tremor, rigidity, and bradykinesia, but also include autonomic disturbances 1 , which were first noted by James Parkinson in his original description. Concretely, the prevalence of clinically relevant dysautonomia in PD exceeds 50% 2 . The period between the onset of neurodegeneration and appearance of the cardinal motor signs is referred to as premotor or prodromal phase of PD and its duration has been estimated to be from years to decades 3 . During this phase patients later diagnosed with PD have more autonomic symptoms than control subjects 3,4 . Likewise, existing reports indicate that autonomic dysfunction occurs before any medical intervention and often precedes motor disturbances 5 .All three branches of the autonomic nerve system (ANS) are affected in PD 6 . Sympathetic cardioneuropathy ...