Topological network analysis of patient similarity for precision management of acute blood pressure in spinal cord injury
- University of California, San Francisco, United States
- University of New Mexico School of Medicine, United States
- Lawrence Berkeley National Laboratory, United States
- Santa Clara Valley Medical Center, United States
- University of Minnesota, United States
Abstract
Background: Predicting neurological recovery after spinal cord injury (SCI) is challenging. Using topological data analysis, we have previously shown that mean arterial pressure (MAP) during SCI surgery predicts long-term functional recovery in rodent models, motivating the present multicenter study in patients.
Methods: Intra-operative monitoring records and neurological outcome data were extracted (n=118 patients). We built a similarity network of patients from a low-dimensional space embedded using a non-linear algorithm, Isomap, and ensured topological extraction using persistent homology metrics. Confirmatory analysis was conducted through regression methods.
Results: Network analysis suggested that time outside of an optimum MAP range (hypotension or hypertension) during surgery was associated with lower likelihood of neurological recovery at hospital discharge. Logistic and LASSO regression confirmed these findings, revealing an optimal MAP range of 76-[104-117] mmHg associated with neurological recovery.
Conclusion: We show that deviation from this optimal MAP range during SCI surgery predicts lower probability of neurological recovery and suggest new targets for therapeutic intervention.
Funding: NIH/NINDS: R01NS088475 (ARF); R01NS122888 (ARF); UH3NS106899 (ARF); Department of Veterans Affairs: 1I01RX002245 (ARF), I01RX002787 (ARF); Wings for Life Foundation (ARF)(ATE); Craig H. Neilsen Foundation (ARF); and DOD: SC150198 (MSB); SC190233 (MSB).
Data availability
Source data has been deposited to the Open Data Commons for Spinal Cord Injury (odc-sci.org; RRID:SCR_016673) under the accession number ODC-SCI:245 (doi: 10.34945/F5R59) and ODC-SCI:246 (doi: 10.34945/F5MG68)
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Intraoperative time series mean arterial pressure and heart rate after spinal cord injury in patients in a multi-site retrospective TRACK-SCI cohort: site 2 of 2Open Data Commons for Spinal Cord Injury, ODC-SCI:246.
Article and author information
Author details
Funding
National Institute of Neurological Disorders and Stroke (R01NS088475)
- Adam R Ferguson
National Institute of Neurological Disorders and Stroke (UG3NS106899)
- Adam R Ferguson
U.S. Department of Veterans Affairs (1I01RX002245)
- Adam R Ferguson
U.S. Department of Veterans Affairs (I01RX002787)
- Adam R Ferguson
Wings for Life Foundation
- Abel Torres Espín
Wings for Life Foundation
- Adam R Ferguson
Craig H. Neilsen Foundation
- Adam R Ferguson
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: This study constitutes a retrospective data analysis. All data was de-identified before pre-processing and analysis. Protocols for retrospective data extraction were approved by Institutional Research Board (IRB) under protocol numbers 11-07639 and 11-06997.
Copyright
© 2021, Torres Espín et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Topological network analysis of patient similarity for precision management of acute blood pressure in spinal cord injury
eLife 10:e68015.
https://doi.org/10.7554/eLife.68015
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