Lesion location and other predictive factors of dysphagia and its complications in acute stroke

Abstract

Background and aims: Early detection of dysphagia is crucial in stroke patients as a result of increased morbidity and mortality due to malnutrition and respiratory tract infections. The aim of this study was to identify possible predictors of the onset of dysphagia following stroke in order to be able to act precociously.

Methods: Observational, prospective study in which a Volume-Viscosity Swallow Test (V-VST) was carried out in the first 72 h following admission to assess dysphagia in acute stroke patients with a previous result of <3 in the Eating Assessment Tool-10. Lesions were analysed by computed tomography and/or magnetic resonance, using the ABC/2 formula to calculate their volume. Likewise, 3-month follow-up was carried out for the evaluation of the occurrence of respiratory tract infections and deaths.

Results: Out of 106 patients admitted for acute stroke, 60 (56.60%) presented dysphagia (44.40% showing alterations in the effectiveness of swallowing and 33.30% in its safety). The factors that were related to dysphagia were: older age (76.40 ± 11.50 vs 66.37 ± 13.85 years, p = 0.0001), stroke severity as measured on the National Institute of Health Stroke Scale (6.81 ± 5.83 vs 3.38 ± 3.46, p = 0.001) and greater volume of the lesion (23.47 ± 47.15 vs 7.50 ± 14.53 ml, p = 0.042). The variables that were influenced by a greater lesion size were the presence of cough, oxygen desaturation and impaired labial seal. Dysphagia was not affected by the lateralization of the lesion or by the type of stroke (ischaemic/haemorrhagic). Despite the fact that 68.80% of the patients with a temporoparietal lesion presented dysphagia, no significant differences were observed regarding the location of the lesion in the regions studied. 27.3% of the patients with frontal lesions presented respiratory infections after discharge (p = 0.018), a condition which was also observed in 20.0% of patients with dysphagia (p = 0.044). Mortality during the 3-month follow-up period was 20.0% for patients with a positive V-VST (p = 0.005), due to respiratory infection in 66.6% of the cases (p = 0.0001).

Conclusions: Post-stroke dysphagia was associated with the occurrence of respiratory tract infection and mortality. Our study also provides more information about how certain demographic and clinical factors, as well as neuroimaging patterns, influence dysphagia. This fact may help to identify at an early stage those patients with a greater risk of developing swallowing alterations.

Keywords: Dysphagia; Stroke; Swallowing; V-VST.