Maria Raquel Soares

Teste de caminhada de seis minutos: valores de referência para adultos saudáveis no Brasil

OBJETIVO: Desenvolver equacoes de regressao para a distância caminhada no teste de caminhada de seis minutos (DTC6) em adultos saudaveis (20-80 anos de idade) no Brasil. METODOS: Foram incluidos 132 voluntarios (66 homens) sem doencas respiratorias ou cardiacas, assim como sem comorbidades que afetassem a deambulacao. Os voluntarios completaram tres testes de caminhada de seis minutos. Foram obtidos antes e ao final de cada teste: SpO2, FC maxima e escores da escala de Borg para dispneia e fadiga de pernas. Os dados incluidos na analise final foram os derivados do teste com a maior DTC6. RESULTADOS: Os valores medios de DTC6 foram de 566 ± 87 m e 538 ± 95 m em homens e mulheres, respectivamente (p = 0,08). A DTC6 aumentou com a estatura e diminuiu com a idade e com o indice de massa corporea (IMC). O melhor modelo ajustado foi o quadratico. A equacao derivada para ambos os sexos foi: DTC6 = 511 + altura2 (cm) × 0,0066 - idade2 × 0,030 - IMC2 × 0,068. Esta equacao explicou 55% da variacao na DTC6. CONCLUSOES: Valores de referencia com uma elevada variância explicada foram derivados por um modelo quadratico de regressao em adultos saudaveis com ampla variacao de idade no Brasil.

Destaques das diretrizes de doenças pulmonares intersticiais da Sociedade Brasileira de Pneumologia e Tisiologia

Interstitial lung diseases (ILDs) are heterogeneous disorders, involving a large number of conditions, the approach to which continues to pose an enormous challenge for pulmonologists. The 2012 Brazilian Thoracic Association ILD Guidelines were established in order to provide Brazilian pulmonologists with an instrument that can facilitate the management of patients with ILDs, standardizing the criteria used for the diagnosis of different conditions and offering guidance on the best treatment in various situations. The objective of this article was to briefly describe the highlights of those guidelines.

Comparison between reference values for FVC, FEV1, and FEV1/FVC ratio in White adults in Brazil and those suggested by the Global Lung Function Initiative 2012

OBJECTIVE: To evaluate the spirometry values predicted by the 2012 Global Lung Function Initiative (GLI) equations, which are recommended for international use, in comparison with those obtained for a sample of White adults used for the establishment of reference equations for spirometry in Brazil. METHODS: The sample comprised 270 and 373 healthy males and females, respectively. The mean differences between the values found in this sample and the predicted values calculated from the GLI equations for FVC, FEV1, and VEF1/FVC, as well as their lower limits, were compared by paired t-test. The predicted values by each pair of equations were compared in various combinations of age and height. RESULTS: For the males in our study sample, the values obtained for all of the variables studied were significantly higher than those predicted by the GLI equations (p < 0.01 for all). These differences become more evident in subjects who were shorter in stature and older. For the females in our study sample, only the lower limit of the FEV1/FVC ratio was significantly higher than that predicted by the GLI equation. CONCLUSIONS: The predicted values suggested by the GLI equations for White adults were significantly lower than those used as reference values for males in Brazil. For both genders, the lower limit of the FEV1/FVC ratio is significantly lower than that predicted by the GLI equations.

Change in FVC and survival in chronic fibrotic hypersensitivity pneumonitis

The predictive value of the decline in FVC by ≥10% on survival in patients with fibrotic hypersensitivity pneumonitis is unknown. Of 112 patients included, 66 (59%) had surgical lung biopsies. Patients with ≥10% decline in predicted FVC after 6–12 months had a significantly increased risk of all-cause mortality (median survival 53 months, 95% CI 37 to 69 vs 139 months, 95% CI 66 to 212 months, p=0.007). On multivariate analysis remained associated with increasing mortality: decline in FVC by ≥10% (HR 4.13, 95% CI 1.96 to 8.70, p=0.005), lower FVC% (HR 1.03, 95% CI 1.01 to 1.05, p=0.003) and with decreasing mortality improvement with antigen avoidance (HR 0.18, 95% CI 0.04 to 0.77, p=0.021).

Lung volumes and airway resistance in patients with a possible restrictive pattern on spirometry

ABSTRACT Objective: Many patients with proportional reductions in FVC and FEV1 on spirometry show no reduction in TLC. The aim of this study was to evaluate the role that measuring lung volumes and airway resistance plays in the correct classification of patients with a possible restrictive pattern on spirometry. Methods: This was a prospective study involving adults with reduced FVC and FEV1, as well as an FEV1/FV(C) ratio within the predicted range. Restrictive lung disease (RLD) was characterized by TLC below the 5th percentile, as determined by plethysmography. Obstructive lung disease (OLD) was characterized by high specific airway resistance, significant changes in post-bronchodilator FEV1, or an FEF25-75% < 50% of predicted, together with a high RV/TLC ratio. Nonspecific lung disease (NLD) was characterized by TLC within the predicted range and no obstruction. Combined lung disease (CLD) was characterized by reduced TLC and findings indicative of airflow obstruction. Clinical diagnoses were based on clinical suspicion, a respiratory questionnaire, and the review of tests of interest. Results: We included 300 patients in the study, of whom 108 (36%) were diagnosed with RLD. In addition, 120 (40%) and 72 (24%) were diagnosed with OLD/CLD and NLD, respectively. Among the latter, 24 (33%) were clinically diagnosed with OLD. In this sample, 151 patients (50.3%) were obese, and obesity was associated with all patterns of lung disease. Conclusions: Measuring lung volumes and airway resistance is often necessary in order to provide an appropriate characterization of the pattern of lung disease in patients presenting with a spirometry pattern suggestive of restriction. Airflow obstruction is common in such cases.