Risk factors of dysphagia in patients with ischemic stroke: A meta-analysis and systematic review

Postextubation dysphagia management in Danish intensive care units: A national survey

BACKGROUND

Postextubation dysphagia (PED) is a common complication to endotracheal intubation in critically ill patients and may lead to pneumonia, prolonged ventilation, longer hospital stays, and increased mortality. Recognizing dysphagia is paramount to preventing adverse events. The aim of this study was to describe PED management by investigating practice in Danish intensive care units (ICUs) focusing on current practice in 2023 (screening, prevention, and treatment), perceived best practice (barriers and facilitators), and when possible, to compare practice in 2017 and 2023.

METHODS

Self-reported, cross-sectional survey of dysphagia practice in Danish ICUs administered from April to May 2023. In addition, data were compared with the 2017 Dysphagia in Intensive Care Evaluation study, when possible.

RESULTS

Only half of Danish ICUs reported to have a PED protocol, and less than half routinely screen patients for dysphagia after extubation. Most common screening methods were the oral mechanism examination, water test, and Facio-oral tract therapy. Nurses and physicians often relied on an overall physical assessment of the patient. Best treatment methods were uniformly agreed to be patient positioning, modification of food and fluids, use of ergonomic utensils, and compensatory maneuvers. Key barriers to dysphagia management were lack of specialized staff, under-recognition of dysphagia as a health issue, and lack of standardized protocols.

CONCLUSION

Awareness of PED is increasing and identification, prevention, and treatment is slowly improving, but systematic implementation of protocols for dysphagia screening and treatment could enhance dysphagia management in Danish ICUs.

Swallowing muscle mass contributes to post-stroke dysphagia in ischemic stroke patients undergoing mechanical thrombectomy

BACKGROUND

Neurogenic dysphagia is a frequent complication of stroke and is associated with aspiration pneumonia and poor outcomes. Although ischaemic lesion location and size are major determinants of the presence and severity of post-stroke dysphagia, little is known about the contribution of other acute stroke-unrelated factors. We aimed to analyse the impact of swallowing and non-swallowing muscles measurements on swallowing function after large vessel occlusion stroke.

METHODS

This retrospective study was based on a prospective registry of consecutive ischaemic stroke patients. Patients who underwent mechanical thrombectomy between July 2021 and June 2022 and received a flexible endoscopic evaluation of swallowing (FEES) within 5 days after admission were included. Demographic, anthropometric, clinical, and imaging data were collected from the registry. The cross-sectional areas (CSA) of selected swallowing muscles (as a surrogate marker for swallowing muscle mass) and of cervical non-swallowing muscles were measured in computed tomography. Skeletal muscle index (SMI) was calculated and used as a surrogate marker for whole body muscle mass. FEES parameters, namely, Functional Oral Intake Scale (FOIS, as a surrogate marker for dysphagia presence and severity), penetration aspiration scale, and the presence of moderate-to-severe pharyngeal residues were collected from the clinical records. Univariate and multivariate ordinal and logistic regression analyses were performed to analyse if total CSA of swallowing muscles and SMI were associated with FEES parameters.

RESULTS

The final study population consisted of 137 patients, 59 were female (43.1%), median age was 74 years (interquartile range 62-83), median baseline National Institutes of Health Stroke Scale score was 12 (interquartile range 7-16), 16 patients had a vertebrobasilar occlusion (11.7%), and successful recanalization was achieved in 127 patients (92.7%). Both total CSA of swallowing muscles and SMI were significantly correlated with age (rho = -0.391, P < 0.001 and rho = -0.525, P < 0.001, respectively). Total CSA of the swallowing muscles was independently associated with FOIS (common adjusted odds ratio = 1.08, 95% confidence interval = 1.01-1.16, P = 0.029), and with the presence of moderate-to-severe pharyngeal residues for puree consistencies (adjusted odds ratio = 0.90, 95% confidence interval = 0.81-0.99, P = 0.036). We found no independent association of SMI with any of the FEES parameters.

CONCLUSIONS

Baseline swallowing muscle mass contributes to the pathophysiology of post-stroke dysphagia. Decreasing swallowing muscle mass is independently associated with increasing severity of early post-stroke dysphagia and with increased likelihood of moderate-to-severe pharyngeal residues.

FOXP3 gene is associated with susceptibility to ischemic stroke in the Chinese population

AIM

Immunoinflammatory response plays an important role in the pathophysiological process of ischemic stroke (IS). Forkhead box P3 (FOXP3) is a master regulator for immune cells. Polymorphisms of FOXP3 gene might contribute to the susceptibility of IS. This study aimed to explore the association between FOXP3 gene polymorphisms (rs3761548 and rs2232365) and IS susceptibility in the Chinese Han population.

METHODS

Polymerase chain reaction and Sanger sequencing were used to detect the genotype of FOXP3 gene rs3761548 and rs2232365 polymorphisms.

RESULTS

Smoking, diabetes mellitus (DM), and HBP histories, higher TG and HDL-C levels were more frequently observed in IS patients than in controls. In comparison with rs3761548 GG genotype, GT genotype (OR = 1.573, 95 %CI = 1.030-2.402; adjusted: OR = 1.736, 95 %CI = 1.070-2.817) and GT + TT vs. GG model (OR = 1.581, 95 %CI = 1.0449-2.382; adjusted: OR = 1.720, 95 %CI = 1.074-2.755) of rs3761548 polymorphism was significantly correlated with elevated ischemic stroke susceptibility both at prior and after adjusted by smoking, HBP, DM, TG and HDL-C. Recessive model of rs2232365 polymorphism could elevate the susceptibility of ischemic stroke (OR = 11.962, 95 %CI = 1.144-3.3363; adjusted: OR = 1.876, 95 %CI = 1.016-3.463). Besides, rs3761548 dominant model (OR = 2.757, 95 %CI = 1.379-5.552; adjusted: OR = 2.601, 95 %CI = 1.268-5.336) and rs2232365 recessive model (OR = 3.103, 95 %CI = 1.463-6.583; adjusted: OR = 3.545, 95 %CI = 1.600-7.855) were related to the severity of ischemic stroke.

CONCLUSION

FOXP3 gene rs3761548 and rs2232365 polymorphisms were risk factors for susceptibility and severity of IS.

Effect of a systemic intervention combined with a psychological intervention in stroke patients with oropharyngeal dysfunction

BACKGROUND

Stroke frequently results in oropharyngeal dysfunction (OD), leading to difficulties in swallowing and eating, as well as triggering negative emotions, malnutrition, and aspiration pneumonia, which can be detrimental to patients. However, routine nursing interventions often fail to address these issues adequately. Systemic and psychological interventions can improve dysphagia symptoms, relieve negative emotions, and improve quality of life. However, there are few clinical reports of systemic interventions combined with psychological interventions for stroke patients with OD.

AIM

To explore the effects of combining systemic and psychological interventions in stroke patients with OD.

METHODS

This retrospective study included 90 stroke patients with OD, admitted to the Second Affiliated Hospital of Qiqihar Medical College (January 2022-December 2023), who were divided into two groups: regular and coalition. Swallowing function grading (using a water swallow test), swallowing function [using the standardized swallowing assessment (SSA)], negative emotions [using the self-rating anxiety scale (SAS) and self-rating depression scale (SDS)], and quality of life (SWAL-QOL) were compared between groups before and after the intervention; aspiration pneumonia incidence was recorded.

RESULTS

Post-intervention, the coalition group had a greater number of patients with grade 1 swallowing function compared to the regular group, while the number of patients with grade 5 swallowing function was lower than that in the regular group (P < 0.05). Post-intervention, the SSA, SAS, and SDS scores of both groups decreased, with a more significant decrease observed in the coalition group (P < 0.05). Additionally, the total SWAL-QOL score in both groups increased, with a more significant increase observed in the coalition group (P < 0.05). During the intervention period, the total incidence of aspiration and aspiration pneumonia in the coalition group was lower than that in the control group (4.44% vs 20.00%; P < 0.05).

CONCLUSION

Systemic intervention combined with psychological intervention can improve dysphagia symptoms, alleviate negative emotions, enhance quality of life, and reduce the incidence of aspiration pneumonia in patients with OD.

Causal relations between ischemic stroke and epilepsy: A bidirectional Mendelian randomization study

Background

Although previous studies have reported a bidirectional relationship between ischemic stroke (IS) and epilepsy, the existence of a causal nexus and its directionality remains a topic of controversy.

Methods

The single nucleotide polymorphisms (SNPs) associated with IS were extracted from the Genome-Wide Association Study (GWAS) database. Pooled genetic data encompassing all epilepsy cases, as well as generalized and focal epilepsy subtypes, were acquired from the International League Against Epilepsy's GWAS study. In this study, the primary analysis approach utilized the inverse variance weighting (IVW) method as the main analytical technique. To enhance the robustness of the findings against potential pleiotropy, additional sensitivity analyses were conducted.

Results

In the forward analysis, the IVW method demonstrated that IS was associated with an increased risk of all epilepsy (odds ratio (OR) = 1.127, 95 % confidence interval (CI) = 1.038-1.224, P = 0.004) and generalized epilepsy (IVW: OR = 1.340, 95 % CI = 1.162-1.546, P = 5.70 × 10-5). There was no substantial causal relationship observed between IS and focal epilepsy (P > 0.05). Furthermore, generalized epilepsy, focal epilepsy, and all epilepsy did not show a causal relationship with IS.

Conclusion

This Mendelian randomization (MR) analysis demonstrates that IS increases the risk of developing epilepsy, especially generalized epilepsy. Conversely, no clear causal association was found between epilepsy and the onset of stroke. Therefore, the possible mechanisms of the effect of epilepsy on the pathogenesis of IS still need to be further investigated.

Transient postictal dysphagia in older adults with focal structural epilepsy

OBJECTIVE

Seizures can cause transient neurological symptoms, such as hemiparesis and aphasia. However, temporary swallowing changes leading to postictal dysphagia have not been previously described. Therefore, this study evaluated the presence of swallowing disorders following seizure. In addition, dysphagia severity and duration of any recovery from dysphagic symptoms were investigated.

METHODS

The local clinical database of all fiberoptic endoscopic evaluation of swallowing (FEES) examinations performed from 2008 to 2019 was screened for patients diagnosed with seizures, but excluding patients with intensive care unit admission or intubation >24 h. Patient charts were evaluated to identify preexisting dysphagia or potential concurrent medical causes for dysphagia, including hyponatremia, increased intracranial pressure, sepsis, or other encephalopathies associated with infections, or other possible causes at the time of admission. Patients receiving >.5 defined daily doses of benzodiazepines or neuroleptics were also excluded. Age, sex, seizure semiology and etiology, comorbidities, concurrent pneumonia, and dysphagia course during hospitalization were evaluated as predictors of the occurrence of dysphagia or its potential duration.

RESULTS

We identified 41 patients with dysphagia following a seizure, without evidence of any concurrent cause of swallowing dysfunction. These patients all presented with focal structural epilepsy, they had a mean age of 79 ± 11.3 years (range = 44-95 years), and 21 were women. The mean Elixhauser Comorbidity Score was 4.8. Hospital-acquired pneumonia was detected in 21 patients (51.2%). FEES diagnosed mild and severe dysphagia in 21 (51.2%) and 20 (48.8%) patients, respectively. Dysphagia improved significantly (p = .001) during hospitalization, persisting for an average of 3.9 days (median = 3 days, SD = 2.07 days, range = 1-8 days).

SIGNIFICANCE

Dysphagia is a potential transient neurological deficit following seizure. Our findings suggest that older patients, with focal structural epilepsy, are at risk for postictal dysphagia. Further studies are needed to ascertain the prevalence, complications, and predictors of postictal dysphagia. Dysphagia screening may improve early detection in patients with relevant risk factors, as well as reduce the occurrence of aspiration pneumonia.

The neurorehabilitation of post-stroke dysphagia: Physiology and pathophysiology

Swallowing is a complex process involving the precise contractions of numerous muscles of the head and neck, which act to process and shepherd ingested material from the oral cavity to its eventual destination, the stomach. Over the past five decades, information from animal and human studies has laid bare the complex network of neurones in the brainstem, cortex and cerebellum that are responsible for orchestrating each normal swallow. Amidst this complexity, problems can and often do occur that result in dysphagia, defined as impaired or disordered swallowing. Dysphagia is common, arising from multiple varied disease processes that can affect any of the neuromuscular structures involved in swallowing. Post-stroke dysphagia (PSD) remains the most prevalent and most commonly studied form of dysphagia and, as such, provides an important disease model to assess dysphagia physiology and pathophysiology. In this review, we explore the complex neuroanatomical processes that occur during normal swallowing and PSD. This includes how strokes cause dysphagia, the mechanisms through which natural neuroplastic recovery occurs, current treatments for patients with persistent dysphagia and emerging neuromodulatory treatments.

Does ICU admission dysphagia independently contribute to delirium risk in ischemic stroke patients? Results from a cohort study

BACKGROUND

Delirium is prevalent in ischemic stroke patients, particularly those in the intensive care unit (ICU), and it poses a significant burden on patients and caregivers, leading to increased mortality rates, prolonged hospital stays, and impaired cognitive function. Dysphagia, a common symptom in critically ill patients with ischemic stroke, further complicates their condition. However, the association between dysphagia and delirium in this context remains unclear. The objective of this study was to investigate the correlation between dysphagia and delirium in ICU patients with ischemic stroke.

METHODS

A retrospective analysis was conducted on adult patients diagnosed with ischemic stroke at a medical center in Boston. Ischemic stroke cases were identified using the ninth and tenth revisions of the International Classification of Diseases. Dysphagia was defined as a positive bedside swallowing screen performed by medical staff on the day of ICU admission, while delirium was assessed using the ICU Confusion Assessment Method and review of nursing notes. Logistic regression models were used to explore the association between dysphagia and delirium. Causal mediation analysis was employed to identify potential mediating variables.

RESULTS

The study comprised 1838 participants, with a median age of approximately 70 years, and 50.5% were female. Among the total study population, the prevalence of delirium was 43.4%, with a higher prevalence observed in the dysphagia group (60.7% vs. 40.8%, p < 0.001) compared to the non-dysphagia group. After adjusting for confounding factors including age, sex, race, dementia, depression, sedative medications, history of falls, visual or hearing deficit, sequential organ failure score, and Glasgow coma score, multifactorial logistic regression analysis demonstrated a significant association between dysphagia and an increased likelihood of delirium (odds ratio [OR]: 1.48; 95% confidence interval [CI]: 1.07-2.05; p = 0.018; E-value = 1.73). Causal mediation analysis revealed that serum albumin levels partially mediated the association between dysphagia and delirium in critically ill patients with ischemic stroke (average causal mediated effect [ACME]: 0.02, 95% CI: 0.01 to 0.03; p < 0.001).

CONCLUSION

ICU admission dysphagia may independently contribute to the risk of delirium in patients with ischemic stroke. Early identification and intervention in ischemic stroke patients with dysphagia may help mitigate the risk of delirium and improve patient prognosis.

Bidirectional causal association between ischemic stroke and five mental disorders

OBJECTIVE

To explore the bidirectional causal association between ischemic stroke and five mental disorders from a genetic perspective using two-sample Mendelian randomization (TSMR).

METHODS

Single-nucleotide polymorphisms (SNPs) associated with ischemic stroke were obtained from the genome-wide association study (GWAS) database, and those closely related to the exposure phenotype and satisfying the three core assumptions of Mendelian randomization were selected as instrumental variables (IVs). The main TSMR analysis was conducted using the inverse variance-weighted (IVW) method, and the robustness of the results was assessed using the weighted median, weighted mode, and MR Egger methods. Heterogeneity test, pleiotropy test, and sensitivity analysis were also conducted to further ensure the accuracy and stability of the research results.

RESULTS

This study found a positive correlation between ischemic stroke and depression [IVW method (FEM): OR = 1.002, 95%CI: 1.000-1.003, P = 0.023<0.05], but no significant causal association with schizophrenia, bipolar disorder, insomnia, or anxiety (P > 0.05). Reverse TSMR analysis showed no causal association between depression, schizophrenia, bipolar disorder, insomnia, anxiety, and ischemic stroke (P > 0.05).

CONCLUSION

This study used TSMR to demonstrate from a genetic perspective that there is a positive correlation between ischemic stroke and depression, which increases the risk of depression. Proactive intervention for ischemic stroke might reduce the risk of depression.

Efficacy and safety of oropharyngeal muscle strength training on poststroke oropharyngeal dysphagia: a systematic review and meta-analysis

OBJECTIVES

To investigate how oropharyngeal muscle strength training affected the safety and performance of swallowing in patients with poststroke oropharyngeal dysphagia.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Cochrane Central Register of Controlled of Trials, Web of Science, PubMed, Embase databases and ClinicalTrials.gov were systematically searched, for publications in English, from database inception to December 2022.

ELIGIBILITY CRITERIA

Studies comparing the effect of oropharyngeal muscle strength training with conventional dysphagia therapy in patients with poststroke. Penetration-Aspiration Scale (PAS) and Functional Oral Intake Scale (FOIS) were assessed as the main outcomes.

DATA EXTRACTION AND SYNTHESIS

Two researchers independently screened the literature, extracted data and evaluated the quality of the included studies, with disagreements resolved by another researcher. The Cochrane risk-of-bias tool was used to assess the risk of bias. Review Manager V.5.3 was employed for the meta-analysis. Random effect models were used for meta-analysis.

RESULTS

Seven studies with 259 participants were included in this meta-analysis. The results showed that oropharyngeal muscle strength training could reduce PAS score compared with conventional dysphagia therapy (mean difference=-0.98, 95% CI -1.34 to -0.62, p<0.0001, I2=28%). The results also showed that oropharyngeal muscle strength training could increase FOIS score (mean difference=1.04, 95% CI 0.55 to 1.54, p<0.0001, I2=0%) and the vertical displacement of the hyoid bone (mean difference=0.20, 95% CI 0.01 to 0.38, p=0.04, I2=0%) compared with conventional dysphagia therapy.

CONCLUSION

In patients with poststroke oropharyngeal dysphagia, oropharyngeal muscle strength training can improve swallowing safety and performance.

PROSPERO REGISTRATION NUMBER

CRD42022302471.

Atropine facilitates water-evoked swallows via central muscarinic receptors in anesthetized rats

Anticholinergic medication causes impaired swallowing with hyposalivation. However, the underlying mechanisms by which these drugs modulate the swallowing reflex remain unclear. This study investigated the effects of the muscarinic acetylcholine receptor (mAChR) nonspecific antagonist atropine on the initiation of swallowing. Experiments were performed on 124 urethane-anesthetized rats. A swallow was evoked by either topical laryngeal application of a small amount of distilled water (DW), saline, citric acid, or capsaicin; upper airway distention with a continuous airflow; electrical stimulation of the superior laryngeal nerve (SLN); or focal microinjection of N-methyl-d-aspartate (NMDA) into the lateral region of the nucleus of the solitary tract (L-nTS). Swallows were identified by electromyographic bursts of the digastric and thyrohyoid muscles. Either atropine, the peripheral mAChR antagonist methylatropine, or antagonists of mAChR subtypes M1-M5 were intravenously delivered. Atropine at a dose of 1 mg/kg increased the number of DW-evoked swallows compared with baseline and did not affect the number of swallows evoked by saline, citric acid, capsaicin, or upper airway distention. Methylatropine and M1-M5 antagonists did not significantly change the number of DW-evoked swallows. Bilateral SLN transection completely abolished DW-evoked swallows, and atropine decreased the swallowing threshold of SLN electrical stimulation. Finally, microinjection of NMDA receptor antagonist AP-5 into the L-nTS inhibited DW-evoked swallows, and atropine facilitated the initiation of swallowing evoked by NMDA microinjection into this region. These results suggest that atropine facilitates DW-evoked swallows via central mAChR actions.NEW & NOTEWORTHY Atropine facilitated the distilled water (DW)-evoked swallows in anesthetized rats. Atropine decreased the swallowing threshold evoked by electrical stimulation of the superior laryngeal nerve, which is a primary sensory nerve for the initiation of DW-evoked swallows. Atropine facilitated the swallows evoked by N-methyl-d-aspartate microinjection into the lateral region of the nucleus of the solitary tract, which is involved in the DW-evoked swallows. We speculate that atropine facilitates the DW-evoked swallows via central muscarinic receptor actions.

Gastrointestinal Dysfunction in Stroke

Gastrointestinal (GI) complications are seen in over 50% of ischemic stroke survivors; the most common complications are dysphagia, constipation, and GI bleeding. The bidirectional relationship of the gut-brain axis and stroke has recently gained traction, wherein stroke contributes to gut dysbiosis (alterations in the normal host intestinal microbiome) and gut dysbiosis perpetuates poor functional neurologic outcomes in stroke. It is postulated that the propagation of proinflammatory cells and gut metabolites (including trimethylamine N-oxide and short-chain fatty acids) from the GI tract to the central nervous system play a central role in gut-brain axis dysfunction. In this review, we discuss the known GI complications in acute ischemic stroke, our current knowledge from experimental stroke models for gut-brain axis dysfunction in stroke, and emerging therapeutics that target the gut-brain axis.