Patrick M Kwon1, Steven Lawrence2, Bridget R Mueller3, Julian F Thayer4, Emma K T Benn2, Jessica Robinson-Papp3. 1. Department of Neurology, NYU Grossman School of Medicine, 8714 5th Ave 2nd Floor, Brooklyn, NY, 11209, USA. Patrick.kwon@nyulangone.org. 2. Center for Biostatistics and Department of Population Health Science and Policy, Icahn School of Medicine at Mount Sinai, New York, NY, USA. 3. Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, USA. 4. Department of Psychological Science, School of Social Ecology, University of California at Irvine, Irvine, CA, USA.
Abstract
PURPOSE: Resting heart rate variability (HRV) is an important biomarker linking mental health to cardiovascular outcomes. However, resting HRV is also impaired in autonomic neuropathy, a common and underdiagnosed complication of common medical conditions which is detected by testing autonomic reflexes. We sought to describe the relationship between autonomic reflex abnormalities and resting HRV, taking into consideration medical comorbidities and demographic variables. METHODS: Participants (n = 209) underwent a standardized autonomic reflex screen which was summarized as the Composite Autonomic Severity Score (CASS) and included measures of reflexive HRV, e.g., heart rate with deep breathing (HRDB). Resting HRV measures were: pNN50 (percentage of NN intervals that differ by > 50 ms) and cvRMSSD (adjusted root mean square of successive differences). RESULTS: In univariate analyses, lower resting HRV was associated with: older age, higher CASS, neuropathy on examination, hypertension, diabetes, chronic obstructive pulmonary disease, chronic kidney disease, and psychiatric disease. Adaptive regression spline analysis revealed that HRDB explained 27% of the variability in resting HRV for participants with values of HRDB in the normal range. Outside this range, there was no linear relationship because: (1) when HRDB was low (indicating autonomic neuropathy), resting HRV was also low with low variance; and (2) when HRDB was high, the variance in resting HRV was high. In multivariate models, only HRDB was significantly independently associated with cvRMSSD and pNN50. CONCLUSION: Subclinical autonomic neuropathy, as evidenced by low HRDB and other autonomic reflexes, should be considered as a potential confounder of resting HRV in research involving medically and demographically diverse populations.
PURPOSE: Resting heart rate variability (HRV) is an important biomarker linking mental health to cardiovascular outcomes. However, resting HRV is also impaired in autonomic neuropathy, a common and underdiagnosed complication of common medical conditions which is detected by testing autonomic reflexes. We sought to describe the relationship between autonomic reflex abnormalities and resting HRV, taking into consideration medical comorbidities and demographic variables. METHODS: Participants (n = 209) underwent a standardized autonomic reflex screen which was summarized as the Composite Autonomic Severity Score (CASS) and included measures of reflexive HRV, e.g., heart rate with deep breathing (HRDB). Resting HRV measures were: pNN50 (percentage of NN intervals that differ by > 50 ms) and cvRMSSD (adjusted root mean square of successive differences). RESULTS: In univariate analyses, lower resting HRV was associated with: older age, higher CASS, neuropathy on examination, hypertension, diabetes, chronic obstructive pulmonary disease, chronic kidney disease, and psychiatric disease. Adaptive regression spline analysis revealed that HRDB explained 27% of the variability in resting HRV for participants with values of HRDB in the normal range. Outside this range, there was no linear relationship because: (1) when HRDB was low (indicating autonomic neuropathy), resting HRV was also low with low variance; and (2) when HRDB was high, the variance in resting HRV was high. In multivariate models, only HRDB was significantly independently associated with cvRMSSD and pNN50. CONCLUSION: Subclinical autonomic neuropathy, as evidenced by low HRDB and other autonomic reflexes, should be considered as a potential confounder of resting HRV in research involving medically and demographically diverse populations.
Authors: Alexander Steger; Alexander Müller; Petra Barthel; Michael Dommasch; Katharina Maria Huster; Katerina Hnatkova; Daniel Sinnecker; Alexander Hapfelmeier; Marek Malik; Georg Schmidt Journal: Front Physiol Date: 2019-02-04 Impact factor: 4.566