P722 The steep ramp test is a valid practical test to assess cardiorespiratory fitness in patients with inflammatory bowel disease

Abstract

Abstract Background Comprehensive disease management of inflammatory bowel disease (IBD) requires a holistic approach that extends beyond achieving endoscopic healing. Monitoring health-related physical fitness (HRPF) parameters (i.e. body composition, cardiorespiratory fitness, muscular strength, muscular endurance, and flexibility) may lead to a more proactive approach to managing IBD, as IBD may affect HRPF due to e.g. chronic inflammation, malnutrition, corticosteroid use, and reduced physical activity. Yet, knowledge regarding HRPF in patients with IBD is limited. Assessment of cardiorespiratory fitness (CRF), a key component of HRPF in other chronic diseases, could offer valuable insights into physical capacity and overall health. However, the gold standard, measuring oxygen uptake at peak exercise (VO2peak) achieved during cardiopulmonary exercise testing (CPET) is impractical for widespread implementation in clinical practice. The steep ramp test (SRT), a short-term maximal exercise test on a cycle ergometer, might serve as a less demanding assessment method to facilitate routine assessment of CRF in clinical practice and deliver more practical endpoints for intervention studies. This study aimed to examine the criterion validity of the SRT as compared with CPET in evaluating CRF in patients with IBD. Methods From August 2022 to October 2023, adult patients with IBD in remission or with mild-to-moderate clinical disease activity were consecutively enrolled. Each participant performed a SRT and a CPET within 14 days to examine CRF. The main outcome measures were the achieved work rate at peak exercise (WRpeak) for the SRT (SRT-WRpeak) and VO2peak as well as WRpeak for CPET (CPET-VO2peak and CPET-WRpeak). Validity of the SRT was evaluated with Pearson’s correlation coefficients between SRT-WRpeak and CPET-VO2peak and SRT-WRpeak and CPET-WRpeak. Results A total of 50 participants, with a mean age of 42.9 years and 56% diagnosed with CD, were included (Table 1). One participant was excluded from the analysis due to the inability to achieve a maximal effort during CPET. Mean (±SD) WRpeak attained at the SRT was 4.32 (±1.06) W·kg-1, and mean (±SD) VO2peak and WRpeak achieved during CPET were 33.47 (±9.85) mL·kg-1·min-1 and 2.90 (±0.95) W·kg-1, respectively. Figure 1 illustrates robust linear relationships with very strong correlations between SRT-WRpeak and CPET- VO2peak (r=0.945, p<0.001) and SRT-WRpeak and CPET-WRpeak (r=0.960, p<0.001). Conclusion Results of this study suggest that the SRT is a valid alternative test for examining CRF in patients with IBD, indicating its potential application in both clinical practice and intervention studies. Further research should explore the criterion validity of practical tests for other components of HRPF.