Mortality and Pulmonary Complications of Post-stroke Dysphagia: A Casuistic Review of an Acute Stroke Unit

Introduction: Dysphagia is a common post-stroke neurological disorder. Early screening for dysphagia can identify patients at risk of aspiration, thereby reducing the occurrence of pulmonary complications, morbidity, and mortality in this population.

Objectives: This study aims to evaluate the impact of an intervention in a stroke unit, following a retrospective study carried out in the same unit in 2020, which investigated the association between dysphagia and acute cerebrovascular disease and analyzed the prevalence of readmissions due to respiratory tract infections (RTI) and mortality. An assessment of the factors related to a higher risk of developing post-stroke dysphagia was also performed.

Material and methods: A retrospective observational study analyzed 210 clinical records of patients with acute cerebrovascular disease, including clinical history, neurological examination, imaging, and Gugging Swallowing Screen in the initial 48 hours. Patient follow-up for three months through medical records was used to evaluate RTI and mortality.

Results: Among the 210 clinical records examined, 209 (99.5%) underwent dysphagia assessment, contrasting with the previously reported casuistic from this unit (40.8%). The prevalence of dysphagia was also higher (50.7% vs. 32.4%). Over a three-month follow-up, RTI occurred in 19% of all patients, in 35.8% of all dysphagic patients, and in 67.7% (p<0.001) of those with severe dysphagia. The overall three-month mortality rate was 9.0% and 12.3% in dysphagic patients, particularly in patients with severe dysphagia (29.0%; p<0.001). Compared to the previous report, this study found a decrease of 1.4% in all-cause mortality (9.0% vs. 10.4%), 11.9% in all-cause mortality in dysphagic patients (12.3% vs. 24.2%), and 46% in all-cause mortality in patients with severe dysphagia (29.0% vs. 75.0%). A higher risk of dysphagia was significantly associated with older age (p<0.001), female gender (p<0.006), severe stroke (p<0.001), hemorrhagic stroke (p=0.005), strokes involving the carotid territory (p=0.040), dysarthria (p=0.004), aphasia (p<0.001), and type of aphasia, particularly global and Broca's aphasia (p=0.022).

Conclusions: The recent rates of all-cause mortality at the three-month follow-up, especially in the severe dysphagia group, indicate an overall improvement in the quality of patient care in the stroke unit intervened with regard to dysphagia, while the higher prevalence of RTI post-stroke at three months may not only reflect the larger number of patients screened for dysphagia but also aging, multimorbidity, and the increasing incidence of stroke on the Portuguese population. The type of cerebrovascular disease, vascular territory, age, gender, National Institutes of Health Stroke Scale and Glasgow Coma Scale scores, dysarthria, aphasia, and type of aphasia were significant associated factors to post-stroke dysphagia. The intervention of a multi-professional team with the implementation of a protocol for early dysphagia screening is crucial to optimizing the outcomes of patients with post-stroke dysphagia.