Use of a Nonexercise Estimate for Prestroke Peak Vo₂ During the Acute Stroke Hospital Stay

For individuals with acute stroke, it is difficult to conduct an exercise test to assess peak oxygen consumption (peak Vo₂). Therefore, the purpose of this study was to use a clinically feasible tool for assessing prestroke peak Vo₂ using a nonexercise estimation equation to test whether estimated prestroke peak Vo₂ was related to the functional outcome measures at discharge from the hospital in individuals after an acute stroke. We hypothesized that the estimated prestroke peak Vo₂ would be significantly related to discharge Physical Performance Test (PPT), 6-minute walk test (6MWT), and lower extremity Fugl-Meyer (LEFM) assessment.

Estimated prestroke peak Vo₂ was calculated using a previously validated prediction equation using the following variables: body mass index, age, sex, resting heart rate, and a self-reported measure of physical activity. Outcome measures were assessed 4 days after enrollment or immediately before discharge (whichever occurred first).

Thirty-four participants (mean age = 56.0, SD = 12.6 years; 20 men) with acute stroke were enrolled within 48 hours of admission. For all individuals, mean estimated prestroke peak Vo₂ was 27.3 (SD = 7.4) mL·kg^-1·min^-1 and had a weak, nonsignificant relationship with the PPT (r = 0.19; P = .28), 6MWT (r = 0.10; P = .56), and LEFM (r = 0.32; P = .06). However, when considering sex, women, but not men, had a significant relationship with LEFM (r = 0.73; P = .005) and moderate but nonsignificant relationship with PPT (r = 0.53; P = .06) and 6MWT (r = 0.47; P = .10).

Within 48 hours of stroke admission, we were able to administer a nonexercise equation to estimate prestroke peak Vo₂. For the entire sample, functional measures conducted at discharge were not related to estimated prestroke peak Vo₂. However, when considering sex, the relationship between prestroke Vo₂ and the functional measures was strengthened.