Exploring exercise intolerance in adult patients with persistent post-concussion symptoms after mild traumatic brain injury.

OBJECTIVES

Explore exercise intolerance with the Buffalo Concussion Treadmill Test (BCTT) in adult patients with persisting post-concussion symptoms (PCS). Examine the association between exercise intolerance and persistent post-concussion symptom burden. Explore factors associated with the BCTT symptom threshold.

DESIGN

Cross-sectional study.

PATIENTS: 100 patients (mean age 36.9 [SD 10.6] years; 58% women) with mild traumatic brain injury and persistent PCS.

METHODS

Exercise intolerance was assessed using descriptive statistics and group comparisons. Regression models were applied testing the association between exercise intolerance and symptom burden, and to explore factors associated with symptom threshold.

RESULTS

81% tested positive for exercise intolerance. Patients with exercise intolerance were younger, had a shorter time since injury, more symptoms, and poorer quality of life. Higher symptom burden was associated with increased odds for exercise intolerance (OR: 1.07, 95%CI: 1.01 to 1.13, p = 0.023). Higher heart rate at start of BCTT was associated with a higher symptom threshold (B: 0.34, 95%CI: 0.17 to -0.50, p  <  0.001), while greater anxiety symptoms were associated with lower symptom threshold (B: -0.86, 95%CI: -1.6 to -0.12, p < 0.023) with R2 = 0.21.

CONCLUSION

Exercise intolerance was confirmed in over 80% of the patients. Assessments of exercise intolerance might contribute to a broader understanding and improved rehabilitation of these patients.