Symptoms upon postural change and orthostatic hypotension in adolescents with concussion.

Healthy controls were assessed only once, during pre-season sports physicals, not at time points comparable with the concussion group's acute and recovery visits. The study did not assess re-test reliability of the 1-minute orthostatic hypotension test. Different automated blood pressure monitors were used at different centers, although measurement was standardized and the same monitor was used for each patient's visits. Mood, food intake, time of day and environment were not controlled, although the authors note these factors would not be controlled in routine clinical settings. The concussion group had a significantly higher number of previous concussions than the control group. Some adolescents with concussion were excluded for medications or conditions affecting heart rate, incomplete data, or loss to follow-up. The Prolonged Recovery Group was classified retrospectively after 4 months, and no recovery-time comparisons were performed. Not all concussion participants had sport-related concussion, although controls were athletic.

The authors disclosed no conflicts of interest relevant to this article. The paper is categorized as NIH extramural research support.

Do not use standing lightheadedness or dizziness as proof of orthostatic hypotension after concussion. The adolescents did not meet standard blood pressure criteria more often, and dizziness was linked to abnormal eye movement testing rather than blood pressure criteria.