Heart Rate Variability from Wearable Photoplethysmography Systems: Implications in Sleep Studies at High Altitude
Abstract
:1. Introduction
2. Materials and Methods
2.1. Participants and Data Collection
2.2. Pre-Elaboration
2.3. HRV Analysis
2.4. Statistics
3. Results
3.1. Mt. Rosa Expedition
3.2. Mt. Himalaya Expedition
4. Discussion
4.1. Quality of PPG Recording during Sleep at High Altitude
4.2. HRV Power Spectra
4.3. HRV Self-Similarity
4.4. HRV Entropy
4.5. Comparison among PPG Tachograms
4.6. HRV Changes at High Altitudes
4.7. Limitations
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
Appendix A
RRI | DDI | SSI | dP1 | dP2 | |
---|---|---|---|---|---|
SampEn | 1.047 (0.074) | 1.294 (0.097) ** | 1.295 (0.058) ** | 1.285 (0.052) ** | 1.419 (0.037) ** |
MSEHF | 1.194 (0.061) | 1.026 (0.065) ** | 1.262 (0.061) ** | 1.238 (0.058) ** | 1.194 (0.064) ** |
MSELF | 1.050 (0.054) | 0.750 (0.084) ** | 1.082 (0.058) ** | 1.078 (0.056) | 1.008 (0.053) |
MSEVLF | 1.056 (0.097) | 0.639 (0.085) ** | 1.033 (0.079) * | 1.017 (0.078) * | 1.010 (0.086) ** |
Milan | Camp 1 | p | |
---|---|---|---|
SampEn | |||
RRI | 1.07 (0.19) | 0.96 (0.09) | 0.22 |
DDI | 1.52 (0.17) | 1.49 (0.08) | 0.69 |
SSI | 1.40 (0.15) | 1.07 (0.08) | 0.08 |
dP1 | 1.46 (0.19) | 1.12 (0.06) | 0.14 |
dP2 | 1.53 (0.14) | 1.23 (0.05) | 0.14 |
MSEHF | |||
RRI | 1.43 (0.18) | 1.66 (0.05) | 0.22 |
DDI | 1.19 (0.17) | 1.47 (0.07) | 0.14 |
SSI | 1.48 (0.15) | 1.67 (0.04) | 0.22 |
dP1 | 1.47 (0.15) | 1.67 (0.04) | 0.22 |
dP2 | 1.46 (0.04) | 1.66 (0.04) | 0.14 |
MSELF | |||
RRI | 1.13 (0.15) | 1.17 (0.08) | 0.22 |
DDI | 0.71 (0.26) | 0.91 (0.11) | 0.89 |
SSI | 1.15 (0.14) | 1.15 (0.07) | 0.22 |
dP1 | 1.15 (0.14) | 1.15 (0.07) | 0.22 |
dP2 | 1.13 (0.07) | 1.15 (0.07) | 0.22 |
MSEVLF | |||
RRI | 1.08 (0.27) | 1.13 (0.20) | 0.35 |
DDI | 0.66 (0.20) | 0.77 (0.26) | 0.22 |
SSI | 1.07 (0.26) | 1.16 (0.17) | 0.35 |
dP1 | 1.06 (0.26) | 1.16 (0.17) | 0.35 |
dP2 | 1.07 (0.17) | 1.16 (0.17) | 0.35 |
RRI | DDI | SSI | dP1 | dP2 | |
SampEn | 0.86 [0.65–1.29] | 1.02 [0.78–1.48] | 0.82 [0.68–1.25] | 0.81 [0.65–1.17] | 0.88 [0.69–1.09] |
MSEHF | 1.09 [0.93–1.27] | 1.13 [0.89–1.68] | 1.08 [0.93–1.23] | 1.10 [0.94–1.23] | 1.11 [0.94–1.24] |
MSELF | 1.01 [0.92–1.21] | 1.13 [0.94–1.50] | 1.00 [0.91–1.20] | 1.01 [0.92–1.21] | 1.02 [0.92–1.23] |
MSEVLF | 1.24 [0.73–1.64] | 1.41 [1.25–1.65] | 1.22 [0.78–1.68] | 1.24 [0.79–1.72] | 1.22 [0.79–1.75] |
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RRI | DDI | SSI | dP1 | dP2 | |
Power Spectral Analysis | |||||
VLF (ms2) | 1888 (478) | 1915 (487) ** | 1860 (480) | 1854 (481) | 1855 (477) |
LF (ms2) | 986 (377) | 1180 (523) ** | 1047 (391) ** | 1042 (381) ** | 1038 (392) ** |
HF (ms2) | 383 (129) | 1791 (375) ** | 424 (143) ** | 453 (142) ** | 498 (139) ** |
LF/HF | 3.93 (0.57) | 1.03 (0.32) ** | 2.96 (0.44) ** | 2.74 (0.38) ** | 2.51 (0.32) ** |
Detrended Fluctuation Analysis | |||||
α1 | 1.158 (0.054) | 0.700 (0.096) ** | 1.092 (0.043) ** | 1.076 (0.043) ** | 1.037 (0.035) ** |
α2 | 0.885 (0.029) | 0.819 (0.028) ** | 0.848 (0.016) ** | 0.848 (0.018) ** | 0.846 (0.017) ** |
Entropy Analysis (m = 1) | |||||
SampEn | 1.135 (0.064) | 1.427 (0.12) ** | 1.384 (0.04) ** | 1.415 (0.047) ** | 1.519 (0.044) ** |
MSEHF | 1.342 (0.055) | 1.110 (0.087) ** | 1.391 (0.052) ** | 1.386 (0.051) ** | 1.372 (0.056) ** |
MSELF | 1.205 (0.029) | 0.916 (0.07) ** | 1.212 (0.033) * | 1.211 (0.036) | 1.192 (0.04) * |
MSEVLF | 1.114 (0.063) | 0.775 (0.075) ** | 1.047 (0.072) ** | 1.042 (0.067) ** | 1.039 (0.06) ** |
RRI | DDI | SSI | dP1 | dP2 | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Milan | Camp 1 | p | Milan | Camp 1 | p | Milan | Camp 1 | p | Milan | Camp 1 | p | Milan | Camp 1 | p | |
Power Spectra | |||||||||||||||
VLF (ms2) | 2016 (1.13) | 4827 (0.59) * | 0.04 | 2137 (1.13) | 5421 (0.59) * | 0.04 | 2000 (1.1) | 4598 (0.62) * | 0.04 | 2164 (1.1) | 5137 (0.61) * | 0.04 | 2176 (1.1) | 5128 (0.62) * | 0.04 |
LF (ms2) | 1433 (0.89) | 4346 (0.61) * | 0.04 | 1869 (0.77) | 5008 (0.67) * | 0.04 | 1553 (0.87) | 4476 (0.6) * | 0.04 | 1520 (0.86) | 4391 (0.62) * | 0.04 | 1522 (0.85) | 4388 (0.62) * | 0.04 |
HF (ms2) | 251 (0.76) | 765 (0.73) * | 0.04 | 1627 (0.8) | 3969 (0.9) | 0.08 | 316 (0.75) | 758 (0.81) * | 0.04 | 365 (0.71) | 856 (0.7) * | 0.04 | 432 (0.68) | 921 (0.69) * | 0.04 |
LF/HF | 5.70 (0.67) | 5.68 (0.58) | 0.69 | 1.15 (0.72) | 1.26 (0.76) | 0.89 | 4.91 (0.79) | 5.91 (0.65) * | 0.04 | 4.16 (0.68) | 5.13 (0.55) * | 0.04 | 3.52 (0.7) | 4.76 (0.54) * | 0.04 |
Detrended Fluctuation Analysis | |||||||||||||||
α1 | 1.24 (0.11) | 1.31 (0.04) | 0.69 | 0.62 (0.13) | 0.76 (0.11) | 0.50 | 1.20 (0.07) | 1.26 (0.05) | 0.22 | 1.19 (0.07) | 1.26 (0.03) | 0.14 | 1.14 (0.06) | 1.24 (0.03) * | 0.04 |
α2 | 0.85 (0.08) | 0.91 (0.04) | 0.89 | 0.73 (0.06) | 0.86 (0.05) | 0.22 | 0.79 (0.07) | 0.90 (0.04) | 0.35 | 0.79 (0.06) | 0.90 (0.04) | 0.35 | 0.79 (0.07) | 0.90 (0.04) | 0.35 |
Entropy Analysis (m = 1) | |||||||||||||||
SampEn | 1.14 (0.19) | 1.09 (0.07) | 0.50 | 1.66 (0.16) | 1.77 (0.10) | 0.50 | 1.44 (0.14) | 1.15 (0.07) | 0.14 | 1.51 (0.18) | 1.24 (0.06) | 0.14 | 1.60 (0.16) | 1.32 (0.05) | 0.14 |
MSEHF | 1.54 (0.13) | 1.70 (0.05) | 0.23 | 1.37 (0.15) | 1.49 (0.08) | 0.14 | 1.59 (0.10) | 1.72 (0.03) | 0.22 | 1.58 (0.10) | 1.71 (0.03) | 0.22 | 1.57 (0.03) | 1.70 (0.03) | 0.14 |
MSELF | 1.25 (0.14) | 1.23 (0.06) | 0.23 | 0.83 (0.25) | 0.92 (0.10) | 0.69 | 1.28 (0.13) | 1.23 (0.06) | 0.35 | 1.27 (0.13) | 1.22 (0.06) | 0.22 | 1.25 (0.06) | 1.22 (0.06) | 0.50 |
MSEVLF | 1.14 (0.19) | 1.16 (0.12) | 0.50 | 0.89 (0.20) | 0.95 (0.19) | 0.22 | 1.13 (0.18) | 1.19 (0.11) | 0.35 | 1.12 (0.20) | 1.20 (0.11) | 0.35 | 1.13 (0.11) | 1.19 (0.11) | 0.35 |
RRI | DDI | SSI | dP1 | dP2 | |
---|---|---|---|---|---|
Power Spectra | |||||
VLF | 1.90 [0.89–8.12] | 1.86 [1.00–7.10] | 1.90 [0.91–8.05] | 1.77 [0.90–7.08] | 1.77 [0.84–7.08] |
LF | 2.89 [0.54–11.1] | 2.90 [0.53–9.25] | 2.82 [0.53–10.8] | 2.85 [0.52–10.6] | 2.88 [0.53–10.6] |
HF | 5.04 [1.03–7.36] | 1.75 [0.64–11.9] | 3.45 [1.00–6.94] | 3.17 [0.87–6.52] | 3.14 [0.75–5.92] |
LF/HF | 0.67 [0.47–1.50] | 1.02 [0.28–6.17] | 0.81 [0.53–1.55] | 0.90 [0.60–1.63] | 0.92 [0.70–1.78] |
Detrended Fluctuation Analysis | |||||
α1 | 0.95 [0.84–0.96] | 1.02 [0.74–2.14] | 0.96 [0.80–1.00] | 0.98 [0.83–1.01] | 0.99 [0.86–1.03] |
α2 | 1.03 [0.82–1.19] | 1.06 [0.95–1.17] | 1.04 [0.87–1.19] | 1.04 [0.87–1.20] | 1.04 [0.88–1.20] |
Entropy Analysis (m = 1) | |||||
SampEn | 0.89 [0.78–1.24] | 1.09 [0.85–1.33] | 0.86 [0.79–1.20] | 0.84 [0.74–1.12] | 0.90 [0.76–1.04] |
MSEHF | 1.07 [0.93–1.21] | 1.09 [0.89–1.58] | 1.06 [0.94–1.18] | 1.07 [0.94–1.18] | 1.07 [0.95–1.19] |
MSELF | 0.99 [0.93–1.10] | 1.06 [0.96–1.39] | 0.99 [0.93–1.09] | 0.99 [0.93–1.10] | 1.00 [0.93–1.11] |
MSEVLF | 1.10 [0.73–1.34] | 1.31 [1.21–1.39] | 1.19 [0.75–1.43] | 1.19 [0.75–1.46] | 1.21 [0.76–1.47] |
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Castiglioni, P.; Meriggi, P.; Di Rienzo, M.; Lombardi, C.; Parati, G.; Faini, A. Heart Rate Variability from Wearable Photoplethysmography Systems: Implications in Sleep Studies at High Altitude. Sensors 2022, 22, 2891. https://doi.org/10.3390/s22082891
Castiglioni P, Meriggi P, Di Rienzo M, Lombardi C, Parati G, Faini A. Heart Rate Variability from Wearable Photoplethysmography Systems: Implications in Sleep Studies at High Altitude. Sensors. 2022; 22(8):2891. https://doi.org/10.3390/s22082891
Chicago/Turabian StyleCastiglioni, Paolo, Paolo Meriggi, Marco Di Rienzo, Carolina Lombardi, Gianfranco Parati, and Andrea Faini. 2022. "Heart Rate Variability from Wearable Photoplethysmography Systems: Implications in Sleep Studies at High Altitude" Sensors 22, no. 8: 2891. https://doi.org/10.3390/s22082891
APA StyleCastiglioni, P., Meriggi, P., Di Rienzo, M., Lombardi, C., Parati, G., & Faini, A. (2022). Heart Rate Variability from Wearable Photoplethysmography Systems: Implications in Sleep Studies at High Altitude. Sensors, 22(8), 2891. https://doi.org/10.3390/s22082891