Gait Assessment: An Effective Tool for Posterior Circulation Stroke Diagnosis

On arrival, gait assessment could be a cost-effective screening tool for posterior circulation stroke, especially among patients who present with dizziness or subjective gait abnormality. These are the results of a study presented at the 2023 American Academy of Neurology (AAN) Annual Meeting, held from April 22 to 27, in Boston, Massachusetts.

Previous research has found that among patients with posterior circulation stroke, objective gait abnormality was the most common presenting feature.

In a case-control study, researchers sought to assess whether objective gait abnormality could be a cost-effective prognostication tool for posterior circulation stroke.

To calculate the probability of objective gait abnormality in patients with posterior circulation stroke and mimics, the researchers used confidence intervals (CI), sensitivity (SE), specificity (SP), positive predictive value (PPV), and negative predictive value (NPV).

The researchers defined cases of posterior circulation stroke as “acute ischemic strokes isolated to the posterior cerebral, basilar, or vertebral artery territories.” They defined mimics as “acutely vertiginous patients from other causes.”

The study included a total of 82 patients with posterior circulation stroke (average age, 67; women, 51%) and 104 patients with mimics (average age, 63; women, 51%) with gait assessment at admission.

The findings revealed objective gait abnormality in 69 (84.1%) of posterior circulation stroke cases vs 18 (17.3%) mimics (odds ratio [OR], 25.4; CI, 11.62-55.35; SE 84%; SP 82%; PPV 79%; NPV 87%).

When the researchers stratified by dizziness, objective gait abnormality was recorded in 38 (86%) posterior circulation stroke cases vs 18 (17.3%) mimics (OR, 30.3; CI, 11.13-82.23; SE 86%; SP 83%; PPV 68%; NPV 94%).

Upon stratifying for subjective gait abnormality, the researchers found objective gait abnormality was recorded in 48 (92%) posterior circulation stroke cases vs 16 (21.6%) mimics (OR, 43.5; CI, 13.63-138.83; SE 92%; SP 78%; PPV 75%; NPV 94%).

Overall, at NYU Langone Hospitals, objective gait abnormality was 25.4 times more likely than mimics in patients with posterior circulation stroke. When presenting with dizziness or subjective gait abnormality, these patients were 30.3 times or 43.5 times more likely to have objective gait abnormality. Upon arrival, NPV increased to 94% in patients with dizziness and subjective gait abnormality.

The researchers concluded, “Gait assessment can be used as a cost-effective screening tool to rule out PCS [posterior circulation stroke] on arrival.”

The researchers’ findings warrant further research before clinicians recommend the use of gait assessment as a screening tool for posterior circulation stroke in clinical practice.