Ventilation distribution as a contributor to the functional exercise capacity in patients with systemic sclerosis-associated interstitial lung disease without pulmonary hypertension
Phenotypic differences have been described between patients with systemic sclerosis (SSc)-associated interstitial lung disease (ILD) and SSc-associated pulmonary hypertension, including performance differences in the 6-min walk test (6MWT). Moreover, the correlations between the 6MWT and traditional...
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Associação Brasileira de Divulgação Científica
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| Series: | Brazilian Journal of Medical and Biological Research |
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| Online Access: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2019000800601&lng=en&tlng=en |
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| author | F.M. Andrade A.D. Oliveira A.J. Lopes |
| author_facet | F.M. Andrade A.D. Oliveira A.J. Lopes |
| author_sort | F.M. Andrade |
| collection | DOAJ |
| description | Phenotypic differences have been described between patients with systemic sclerosis (SSc)-associated interstitial lung disease (ILD) and SSc-associated pulmonary hypertension, including performance differences in the 6-min walk test (6MWT). Moreover, the correlations between the 6MWT and traditional pulmonary function tests (PFTs) are weak, indicating the need to search for new parameters that explain exercise performance. Thus, our objective was to evaluate the impact of ventilation distribution heterogeneity assessed by the nitrogen single-breath washout (N2SBW) test and peripheral muscle dysfunction on the exercise capacity in patients with SSc-ILD and limited involvement of the pulmonary parenchyma. In this cross-sectional study, 20 women with SSc-ILD and 20 matched controls underwent PFTs (including spirometry, diffusing capacity for carbon monoxide (DLco), and the N2SBW test) and performed the 6MWT and knee isometric dynamometry. The 6-min walking distance (6MWD, % predicted) was strongly correlated with the phase III slope of the single-breath nitrogen washout (phase III slopeN2SBW) (r=−0.753, P<0.0001) and reasonably correlated with the forced vital capacity (FVC) (r=0.466, P=0.008) and DLco (r=0.398, P=0.011). The peripheral oxygen saturation (SpO2) during exercise was not significantly correlated with any of the pulmonary or muscle function parameters. The phase III slopeN2SBW was the only predictive variable for the 6MWD, whereas quadriceps strength and FVC/DLco were predictive variables for SpO2. Ventilation distribution heterogeneity is one factor that contributes to a lower 6MWD in SSc-ILD patients. In addition, muscle dysfunction and abnormal lung diffusion at least partly explain the decreased SpO2 of these patients. |
| first_indexed | 2024-12-10T13:20:12Z |
| format | Article |
| id | doaj.art-8d17f6b9c7f7455aaff090800ad77169 |
| institution | Directory Open Access Journal |
| issn | 1414-431X |
| language | English |
| last_indexed | 2024-12-10T13:20:12Z |
| publisher | Associação Brasileira de Divulgação Científica |
| record_format | Article |
| series | Brazilian Journal of Medical and Biological Research |
| spelling | doaj.art-8d17f6b9c7f7455aaff090800ad771692022-12-22T01:47:23ZengAssociação Brasileira de Divulgação CientíficaBrazilian Journal of Medical and Biological Research1414-431X52810.1590/1414-431x20198513S0100-879X2019000800601Ventilation distribution as a contributor to the functional exercise capacity in patients with systemic sclerosis-associated interstitial lung disease without pulmonary hypertensionF.M. AndradeA.D. OliveiraA.J. LopesPhenotypic differences have been described between patients with systemic sclerosis (SSc)-associated interstitial lung disease (ILD) and SSc-associated pulmonary hypertension, including performance differences in the 6-min walk test (6MWT). Moreover, the correlations between the 6MWT and traditional pulmonary function tests (PFTs) are weak, indicating the need to search for new parameters that explain exercise performance. Thus, our objective was to evaluate the impact of ventilation distribution heterogeneity assessed by the nitrogen single-breath washout (N2SBW) test and peripheral muscle dysfunction on the exercise capacity in patients with SSc-ILD and limited involvement of the pulmonary parenchyma. In this cross-sectional study, 20 women with SSc-ILD and 20 matched controls underwent PFTs (including spirometry, diffusing capacity for carbon monoxide (DLco), and the N2SBW test) and performed the 6MWT and knee isometric dynamometry. The 6-min walking distance (6MWD, % predicted) was strongly correlated with the phase III slope of the single-breath nitrogen washout (phase III slopeN2SBW) (r=−0.753, P<0.0001) and reasonably correlated with the forced vital capacity (FVC) (r=0.466, P=0.008) and DLco (r=0.398, P=0.011). The peripheral oxygen saturation (SpO2) during exercise was not significantly correlated with any of the pulmonary or muscle function parameters. The phase III slopeN2SBW was the only predictive variable for the 6MWD, whereas quadriceps strength and FVC/DLco were predictive variables for SpO2. Ventilation distribution heterogeneity is one factor that contributes to a lower 6MWD in SSc-ILD patients. In addition, muscle dysfunction and abnormal lung diffusion at least partly explain the decreased SpO2 of these patients.http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2019000800601&lng=en&tlng=enSystemic sclerosisRespiratory function testsVentilationNitrogen single-breath washout testExerciseSix-minute walk test |
| spellingShingle | F.M. Andrade A.D. Oliveira A.J. Lopes Ventilation distribution as a contributor to the functional exercise capacity in patients with systemic sclerosis-associated interstitial lung disease without pulmonary hypertension Brazilian Journal of Medical and Biological Research Systemic sclerosis Respiratory function tests Ventilation Nitrogen single-breath washout test Exercise Six-minute walk test |
| title | Ventilation distribution as a contributor to the functional exercise capacity in patients with systemic sclerosis-associated interstitial lung disease without pulmonary hypertension |
| title_full | Ventilation distribution as a contributor to the functional exercise capacity in patients with systemic sclerosis-associated interstitial lung disease without pulmonary hypertension |
| title_fullStr | Ventilation distribution as a contributor to the functional exercise capacity in patients with systemic sclerosis-associated interstitial lung disease without pulmonary hypertension |
| title_full_unstemmed | Ventilation distribution as a contributor to the functional exercise capacity in patients with systemic sclerosis-associated interstitial lung disease without pulmonary hypertension |
| title_short | Ventilation distribution as a contributor to the functional exercise capacity in patients with systemic sclerosis-associated interstitial lung disease without pulmonary hypertension |
| title_sort | ventilation distribution as a contributor to the functional exercise capacity in patients with systemic sclerosis associated interstitial lung disease without pulmonary hypertension |
| topic | Systemic sclerosis Respiratory function tests Ventilation Nitrogen single-breath washout test Exercise Six-minute walk test |
| url | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2019000800601&lng=en&tlng=en |
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