BACKGROUND: Patient reported outcome measures (PROMs) such as health status (HS) and quality of life (QOL) are frequently used interchangeably while they represent different outcomes. Whether a discrepancy exists in patients with intermittent claudication (IC) in changes over time between HS and QOL is unclear. This study aimed to investigate the strength and the direction of the association between HS and QOL over time in patients with IC that underwent supervised exercise therapy (SET).
MATERIAL AND METHODS: Patients were part of the ELECT multi-center prospective cohort study. One goal of this study was to obtain data on HS and QOL at different time intervals of patients with IC that underwent SET. HS (VascuQOL-6) and QOL (WHOQOL-BREF) were completed at baseline, 3 months, and 6 months follow up. Pearson's correlation coefficients and the associated common variances (R2) were calculated to measure the strength and the direction of the association between HS and QOL in changes between baseline and follow-up moments.
RESULTS: In total, 177 patients were included in data analyses. Only changes in physical QOL and overall QOL had a small correlation with changes over time in HS, at both 3- and 6 months follow up (respectively R2=.14; P < 0.001 and R2 = 0.12; P < 0.001 for physical QOL and R2 = 0.18; P < 0.001 and R2 = 0.13; P < 0.001 for overall QOL).
CONCLUSIONS: This study showed that HS and QOL provide different outcomes in patients with IC that underwent SET. Future studies should be aware of these differences before PROMs are being incorporated as an outcome measure in clinical studies.
- Exercise Therapy
- Health Status
- Intermittent Claudication/diagnosis
- Middle Aged
- Patient Reported Outcome Measures
- Prospective Studies
- Quality of Life
- Time Factors
- Treatment Outcome