The Modified Volume-Viscosity Swallow Test as a Predictor of Aspiration Pneumonia after Acute Ischemic Stroke

Dysphagia is common in patients with acute ischemic stroke patients (AIS) and it increases the risk of aspiration pneumonia after AIS. The volume-viscosity swallow test (V-VST) is a useful dysphagia screening tool. Therefore, we aim to explore the association between dysphagia (using the modified V-VST) and aspiration pneumonia in acute ischemic stroke patients.

All patients with acute ischemic stroke (AIS) admitted during 1 January 2018 and 31 December 2018 were screened in this study by completing the modified V-VST within 24 hours after admission. The information of aspiration pneumonia was obtained from electronic medical system (EMS) and discharge notes.

Among 624 AIS patient, there were 152(24.36%) patients who suffered from aspiration pneumonia (95% CI, 20.65% - 27.35%) during hospitalization. Among all of them, patients with both impaired safety and impaired efficacy (HR, 7.53, 95%CI, 3.42-16.58, P < 0.001)) had a higher risk of aspiration pneumonia than those with only safety impaired (HR, 2.38, 95%CI, 1.40-4.04, P < 0.001) or only efficacy impaired (HR, 2.47, 95%CI, 1.33-4.57, P = 0.004). The risk of aspiration pneumonia was also associated with their completed volume at each viscosity. The patients with all impairment of three viscosities were also found to be related to the higher risk of developing aspiration pneumonia (P = 0.029).

The Modified V-VST is an easy-hand on, reliable screening tool for dysphagia among patients with AIS. Patient subgroup analyses based on the modified V-VST might be able to predict the risk of aspiration pneumonia during hospitalization.