title: Cardiopulmonary exercise testing variables as predictors of long-term outcome in thoracic sarcoidosis.
abstract: Cardiopulmonary exercise testing (CPET) plays an important role in the assessment of functional capacity in patients with interstitial lung disease. The aim of this study was to identify CPET measures that might be helpful in predicting the vital capacity and diffusion capacity outcomes of patients with thoracic sarcoidosis. A longitudinal study was conducted on 42 nonsmoking patients with thoracic sarcoidosis (median age = 46.5 years, 22 females). At the first evaluation, spirometry, the measurement of single-breath carbon monoxide diffusing capacity (D LCOsb) and CPET were performed. Five years later, the patients underwent a second evaluation consisting of spirometry and D LCOsb measurement. After 5 years, forced vital capacity (FVC)% and D LCOsb% had decreased significantly [95.5 (82-105) vs 87.5 (58-103) and 93.5 (79-103) vs 84.5 (44-102), respectively; P < 0.0001 for both]. In CPET, the peak oxygen uptake, maximum respiratory rate, breathing reserve, alveolar-arterial oxygen pressure gradient at peak exercise (P(A-a)O2), and Δ SpO2 values showed a strong correlation with the relative differences for FVC% and D LCOsb% (P < 0.0001 for all). P(A-a)O2 ≥22 mmHg and breathing reserve ≤40% were identified as significant independent variables for the decline in pulmonary function. Patients with thoracic sarcoidosis showed a significant reduction in FVC% and D LCOsb% after 5 years of follow-up. These data show that the outcome measures of CPET are predictors of the decline of pulmonary function.
authors.affiliation: Setor de Provas de Função Respiratória, Universidade do Estado do Rio de Janeiro, Rua Araguaia 1266, Rio de Janeiro, RJ, Brazil. phel.lop@uol.com.br
authors.forename: A J
authors.initials: AJ
authors.lastname: Lopes
authors.forename: S L S
authors.initials: SL
authors.lastname: Menezes
authors.forename: C M
authors.initials: CM
authors.lastname: Dias
authors.forename: J F
authors.initials: JF
authors.lastname: Oliveira
authors.forename: M R M
authors.initials: MR
authors.lastname: Mainenti
authors.forename: F S
authors.initials: FS
authors.lastname: Guimarães
mesh_terms: D000328:Adult; D005080:Exercise Test; D017079:Exercise Tolerance; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption / Q000502:physiology*; D017565:Sarcoidosis, Pulmonary / Q000503:physiopathology*; D012720:Severity of Illness Index; D013147:Spirometry; D014797:Vital Capacity / Q000502:physiology*