Background:CPET is a widely used examination to predict the prognosis of chronic obstructive pulmonary disease or post-transplant lung function, and it has also been examined in the context of respiratory tract involvement and pulmonary hypertension in systemic slerosis (SSc).Objectives:As CPET provides a general overview of the aerobic metabolism, influenced by pulmonary, cardiac and vascular function, the purpose of this investigation was to assess if development of poor overall disease outcome could be predicted by CPET.Methods:Twenty-nine SSc patients (M/F=5/24 DcSSc/LcSSc=16/13) were investigated repeatedly with CPET and followed for a mean of 3.7 (range 1-7) years. The clinical features of the patients were the following: alveolitis (n=15), pulmonary fibrosis (n=16), digital ulcers (n=13), 5 of them required bosentan therapy, macroangiopathy (n=8), GERD (n=26), Barrett metaplasia (n=19), gastrintestinal angiopathy (n=5), motility disorder (n=10), pulmonary artery hypertension (pPulm >40 mmHg) (n=4). The average disease duration was 8.9 years. A composite end point was set up: death or digital ulceration necessitating bosentan therapy or pulmonary hypertension (Ppulm>40mmHg) or the decrease of carbon-monoxide diffusion capacity (δDLCO) > 2%/year, or increase in pulmonary artery pressure (δPpulm) >3mmHg/year). Paralell with the CPET, conventional disease activity check-ups have been performed too (echocardiography, chest CT, resting lung function tests, clinical examinations). The correlations between the CPET mesurements and conventional findings and the predictive value of CPET parameters at the first visit to the future development of the composite end-point have been examined.Results:Various CPET results (anaerobic threshold (AT), work rate (WR), desaturation) have significantly correlated with worsening DLCO (p<0,05; Pearson’s correlation). The change of aT per year (δAT/yr) and the degree of desaturation during exercise predicted the development of poor prognostic end-point (p<0.05 with logistic regression), and the detection of desaturation at the first CPET test was associated with a higher risk of poor prognosis (OR: 5,265 [95% CI 1,077-29,38] p=0.057). In contrast, none of the standard pulmonary or cardiac parameters have proved to be predictive to the end-point in this cohort.Conclusion:CPET parameters correlate well with the standard assessment tools, indicating that this test is feasible in SSc patients too. The changes of aT during follow-up and desaturation are predictive to the appearence of the end point designed to comprise multiple features of the disease. This makes CPET a promising non-invasive examination method to estimate the progression of disease in patients suffering from systemic sclerosis.Disclosure of interests: None declared
