{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T07:08:06Z","timestamp":1784012886175,"version":"3.55.0"},"reference-count":52,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2021,1,28]],"date-time":"2021-01-28T00:00:00Z","timestamp":1611792000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Objective: the complexity of heart-rate variability (HRV) in amyotrophic lateral sclerosis (ALS) patients with different pulmonary capacities was evaluated. Methods: We set these according to their pulmonary capacity, and specifically forced vital capacity (FVC). We split the groups according to FVC (FVC &gt; 50% (n = 29) and FVC &lt; 50% (n = 28)). In ALS, the presence of an FVC below 50% is indicative of noninvasive ventilation with two pressure levels and with the absence of other respiratory symptoms. As the number of subjects per group was different, we applied the unbalanced one-way analysis of variance (uANOVA1) test after three tests of normality, and effect size by Cohen\u2019s d to assess parameter significance. Results: with regard to chaotic global analysis, CFP4 (p &lt; 0.001; d = 0.91), CFP5 (p = 0.0022; d = 0.85), and CFP6 (p = 0.0009; d = 0.92) were enlarged. All entropies significantly increased. Shannon (p = 0.0005; d = 0.98), Renyi (p = 0.0002; d = 1.02), Tsallis (p = 0.0004; d = 0.99), approximate (p = 0.0005; d = 0.97), and sample (p &lt; 0.0001; d = 1.22). Detrended fluctuation analysis (DFA) (p = 0.0358) and Higuchi fractal dimension (HFD) (p = 0.15) were statistically inconsequential between the two groups. Conclusions: HRV complexity in ALS subjects with different pulmonary capacities increased via chaotic global analysis, especially CFP5 and 3 out of 5 entropies.<\/jats:p>","DOI":"10.3390\/e23020159","type":"journal-article","created":{"date-parts":[[2021,1,28]],"date-time":"2021-01-28T09:03:45Z","timestamp":1611824625000},"page":"159","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Complexity Measures of Heart-Rate Variability in Amyotrophic Lateral Sclerosis with Alternative Pulmonary Capacities"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9523-4859","authenticated-orcid":false,"given":"Renata M. M.","family":"Pimentel","sequence":"first","affiliation":[{"name":"Departament of Medicine, Federal University of Santo Paulo (UNIFESP), S\u00e3o Paulo 04024-002, Brazil"},{"name":"Laborat\u00f3rio de Delineamento de Estudo e Escrita Cient\u00edfica, Centro Universit\u00e1rio FMABC, Santo Andr\u00e9 09060-650, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Celso","family":"Ferreira","sequence":"additional","affiliation":[{"name":"Departament of Medicine, Federal University of Santo Paulo (UNIFESP), S\u00e3o Paulo 04024-002, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7477-3805","authenticated-orcid":false,"given":"Vitor","family":"Valenti","sequence":"additional","affiliation":[{"name":"Autonomic Nervous System Center (CESNA) Sao Paulo State University, Mar\u00edlia 17525-900, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8114-9055","authenticated-orcid":false,"given":"David M.","family":"Garner","sequence":"additional","affiliation":[{"name":"Cardiorespiratory Research Group, Department of Biological and Medical Sciences, Faculty of Health and Life Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9966-8072","authenticated-orcid":false,"suffix":"Jr.","given":"Hugo","family":"Macedo","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de Delineamento de Estudo e Escrita Cient\u00edfica, Centro Universit\u00e1rio FMABC, Santo Andr\u00e9 09060-650, Brazil"},{"name":"Department of Community Health, Faculdade de Medicina do ABC, Santo Andr\u00e9 09060-870, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Acary S. Bulle","family":"Oliveira","sequence":"additional","affiliation":[{"name":"Department of Neuromuscular Diseases, UNIFESP, S\u00e3o Paulo 04022-002, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7743-2512","authenticated-orcid":false,"given":"Francisco Naildo Cardoso","family":"Leit\u00e3o","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de Delineamento de Estudo e Escrita Cient\u00edfica, Centro Universit\u00e1rio FMABC, Santo Andr\u00e9 09060-650, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7618-2109","authenticated-orcid":false,"given":"Luiz Carlos","family":"de Abreu","sequence":"additional","affiliation":[{"name":"Department of Integrated Health Education, Federal University of Esp\u00edrito Santo (UFES), Vit\u00f3ria 29040-090, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2084","DOI":"10.1016\/S0140-6736(17)31287-4","article-title":"Amyotrophic lateral sclerosis","volume":"390","author":"Hardiman","year":"2017","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"e6251","DOI":"10.1097\/MD.0000000000006251","article-title":"Different characteristics of ventilator application between tracheostomy- and noninvasive positive pressure ventilation patients with amyotrophic lateral sclerosis","volume":"96","author":"Park","year":"2017","journal-title":"Medicine"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1625","DOI":"10.1016\/j.clinph.2017.06.039","article-title":"The terminal latency of the phrenic nerve correlates with respiratory symptoms in amyotrophic lateral sclerosis","volume":"128","author":"Park","year":"2017","journal-title":"Clin. 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