Evidence map›Paper›PMID 41637364›Full record

ArticleJornal brasileiro de pneumologia : publicacao oficial da Sociedade Brasileira de Pneumologia e Tisilogia2026

Reference equation for measurement of the maximal dynamic inspiratory muscle pressure index (S-Index) in healthy Brazilian adults.

Luis Felipe da Fonseca Reis, Cleber da Penha, Pamela do Carmo Dosso da Silva, Aline Oliveira Martins Soares de Mendonça, Ana Carolina Sebastião da Silva, Clara Pinto Diniz, Flavia Mazzoli-Rocha, Arthur de Sá Ferreira, Agnaldo José Lopes

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In one paragraph

Article in Jornal brasileiro de pneumologia : publicacao oficial da Sociedade Brasileira de Pneumologia e Tisilogia, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

What it found

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2 · The registry

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3 · Its place in the literature

Who cites it

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4 · The record

Corrections and comments

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5 · Who and what money

Authors and funding

9 authors.

Luis Felipe da Fonseca Reis. Programa de Pós-Graduação em Ciências da Reabilitação, Centro Universitário Augusto Motta, Rio de Janeiro (RJ), Brasil.ORCID http://orcid.org/0000-0002-6812-6553
Cleber da Penha. Programa de Pós-Graduação em Ciências da Reabilitação, Centro Universitário Augusto Motta, Rio de Janeiro (RJ), Brasil.ORCID http://orcid.org/0009-0006-7311-8212
Pamela do Carmo Dosso da Silva. Programa de Pós-Graduação em Ciências da Reabilitação, Centro Universitário Augusto Motta, Rio de Janeiro (RJ), Brasil.ORCID http://orcid.org/0009-0004-0155-5400
Aline Oliveira Martins Soares de Mendonça. Programa de Pós-Graduação em Ciências da Reabilitação, Centro Universitário Augusto Motta, Rio de Janeiro (RJ), Brasil.ORCID http://orcid.org/0009-0006-5089-7145
Ana Carolina Sebastião da Silva. Programa de Pós-Graduação em Ciências da Reabilitação, Centro Universitário Augusto Motta, Rio de Janeiro (RJ), Brasil.ORCID http://orcid.org/0009-0009-0201-264X
Clara Pinto Diniz. Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro (RJ), Brasil.ORCID http://orcid.org/0000-0003-1398-7337
Flavia Mazzoli-Rocha. Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro (RJ), Brasil.ORCID http://orcid.org/0000-0003-0972-194X
Arthur de Sá Ferreira. Programa de Pós-Graduação em Ciências da Reabilitação, Centro Universitário Augusto Motta, Rio de Janeiro (RJ), Brasil.ORCID http://orcid.org/0000-0001-7014-2002
Agnaldo José Lopes. Programa de Pós-Graduação em Ciências da Reabilitação, Centro Universitário Augusto Motta, Rio de Janeiro (RJ), Brasil.ORCID http://orcid.org/0000-0001-8598-4878

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

objectivesSeveral equations for calculating maximal inspiratory pressure (MIP) have been validated for the Brazilian population; however, none exist for maximal dynamic inspiratory muscle pressure (S-Index).

methodsThis cross-sectional study was conducted at two centers following approval by the institutional ethics committee. Healthy Brazilian adults were sequentially randomized to assess either the MIP or S-Index. Pulmonary function (spirometry), peripheral muscle strength (handgrip strength of the dominant upper limb - HGdUL), and physical activity level (IPAQ) were also evaluated. The S-Index and MIP values were reported as absolute values and compared using the Wilcoxon paired test. Multiple linear regression was used to develop reference equations. Lower limits of normality (LLNs) were stratified by sex and age using Z-scores, providing cut-off points to define inspiratory muscle weakness via the S-Index Deviation Score (SDS).

resultsThe final sample comprised 214 eutrophic volunteers, 50% men, with a mean age of 43.1 ± 15.0 years. The median MIP was significantly higher than the median S-Index (97.2 [96.7-112.0] vs. 92.5 [80.0-105.0] cmH2O; p<0.001). The predicted equation for the S-Index, which used age, sex, and HGdUL as predictors, was: S-Index = 69.72 + 10.765×sex (men = 1; women = 0) - 0.211×age + 0.797×HGdUL. Additionally, the LLNs and cut-off points for ventilatory muscle weakness by sex and age group were established.

conclusionsThis study provides the first reference values for the S-Index in healthy, eutrophic Brazilian adults, including LLNs and cut-off points for diagnosing ventilatory muscle weakness.

Indexed as

InhalationMaximal Respiratory PressuresMuscle StrengthRespiratory MusclesAdultBrazilCross-Sectional StudiesFemaleHand StrengthHumansMaleMiddle AgedReference ValuesSpirometryStatistics, NonparametricYoung Adult

Identifiers

PMID41637364
PMCPMC13143645

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.