Table 4. Results of cardiopulmonary exercise testing according to the decline in pulmonary function after a 5-year follow-up in thoracic sarcoidosis patients.
| Significant variables* | Decline in pulmonary function+ | |||||
|---|---|---|---|---|---|---|
| Present (N = 18) | Absent (N = 24) | RR | 95%CI | |||
| N | % | N | % | |||
| Peak VO2 ≤50% of predicted | 17 | 94.4 | 2 | 8.3 | 20.6 | 3.01-140.8 |
| BR max ≥40 breaths/min | 16 | 88.9 | 6 | 25.0 | 7.27 | 1.91-27.8 |
| Breathing reserve ≤40% | 17 | 94.4 | 2 | 8.3 | 20.6 | 3.01-140.8 |
| P(A-a)O2 ≥22 mmHg | 17 | 94.4 | 1 | 4.2 | 22.7 | 3.32-154.9 |
| Δ SpO2 ≥4% | 17 | 94.4 | 3 | 12.5 | 18.7 | 2.73-128.0 |
RR = relative risk; 95%CI = 95% confidence interval; peak VO2 = peak oxygen uptake; BR max = maximum respiratory rate; P(A-a)O2 = alveolar-arterial oxygen pressure gradient at peak exercise; Δ SpO2 = difference between peak and resting oxygen saturation. *Significant variables resulting from Spearman's rank correlation between the relative variations of pulmonary function tests and cardiopulmonary exercise testing measures (optimal cut-off points of the area under the ROC curve). +Decrease >10% in relation to the initial values of forced vital capacity or single-breath diffusion of carbon monoxide across the lung.