Parkinson's disease effect on autonomic modulation: an analysis using geometric indices

Abstract

Background: Parkinson's disease (PD) produces autonomic changes, indicating lower parasympathetic modulation and global variability, but these changes need further studying regarding geometric methods. Objective: To investigate the autonomic modulation in individuals with PD using heart rate variability (HRV) indices obtained through geometric methods. Methods: This is a cross-sectional study that assessed 50 individuals, split into two groups: PD group (PDG; n=26; 75.36±5.21 years) and control group (CG; n=24; 75.36±5.21 years). We evaluated the autonomic modulation by measuring the heart rate beat-to-beat for 30 min with the individual in supine rest using a heart rate monitor and assessed geometric indices (RRtri, TINN, SD1, SD2, SD1/SD2 ratio, and qualitative analysis of the Poincaré plot). Results: Significant reductions were found in RRtri, TINN, SD1, and SD2 indices among PDG compared to CG. Regarding the SD1/SD2 ratio, no significant changes were detected between the groups. The Poincaré plot demonstrated that individuals with PD had lower beat-to-beat dispersion in RR intervals, in addition to greater long-term dispersion of RR intervals compared to CG. Conclusions: The results suggest a reduction in the parasympathetic autonomic modulation and global variability in individuals with PD compared to controls, regardless of sex, age, and body mass index.

Autonomic and cardiorespiratory responses to the active tilt test in individuals with Parkinson disease: cross-sectional study

“…These results, together with the reduction observed in the rMSSD, HFms 2 and SD1, might indicate that individuals with PD present increased sympathetic and reduced parasympathetic modulation, suggesting a reduction in the complexity of the RR intervals series of the PDG. Similar results have been found by Rocha et al, 8 Stoco-Oliveira et al, 29 and Harnold et al 30 …”

“…These results, together with the reduction observed in the rMSSD, HFms 2 and SD1, might indicate that individuals with PD present increased sympathetic and reduced parasympathetic modulation, suggesting a reduction in the complexity of the RR intervals series of the PDG. Similar results have been found by Rocha et al, 8 Stoco-Oliveira et al, 29 and Harnold et al 30 Cardiovascular autonomic dysregulation in PD has been attributed to involvement of both the central as well as the peripheral postganglionic autonomic nervous system. 31 Solla et al 32 have suggested that the autonomic dysfunction present in PD is associated with significant increase in morbidity and mortality.…”

Does length of time since diagnosis in Parkinson’s disease influence heart rate variability? A cross-sectional study

“…Studies have shown that the reduction in the SDNN index can occur at the beginning of the disease, thus indicating involvement of the ANS physiology 37 . Ke et al 3 8 also demonstrated that a significant reduction in global variability occurred among individuals with PD, compared with individuals without the disease. Those authors reported SDNN values of 45.50 ms for the control group and 34.50 ms for the Parkinson group, which were higher than the values found in the current study, which were 26.19 ms for the control group, 14.10 ms for the group with shorter time since diagnosis and 14.63 ms for the group with longer time since diagnosis.…”

“…These intervals are associated with the influences of the ANS on the sinus node 7 . Studies using this analysis among individuals with PD have demonstrated that HRV is lower in this population 8,9,10 . This is an autonomic dysfunction that could be a consequence of autonomic regulatory degeneration in the brain and peripheral autonomic ganglia 9 .…”