Risk factors for oropharyngeal dysphagia in cardiovascular diseases.

Some conditions consolidated as risk factors for oropharyngeal dysphagia have already been identified in other diseases, such as neurological. Studies on cardiovascular diseases concentrate in individuals in the postoperative period; thus, it is unknown if these same factors occur in individuals hospitalized for clinical or surgical treatment of these diseases. Objective to correlate predictive risk factors for oropharyngeal dysphagia in individuals with cardiovascular disease admitted at a reference cardiology hospital. Methodology This is a retrospective clinical study. Medical records of 175 individuals hospitalized for clinical and/or surgical treatment at a reference cardiology hospital from January to June 2017, attendants of the Speech-Language Pathology and Nutrition team, were analyzed. Of these, 100 records were included in the study: 41 females and 59 males (mean age 67.56 years). Deaths and individuals from 0 to 18 years were excluded. Stroke, malnutrition, age and prolonged orotracheal intubation were considered predictive risk factors for oropharyngeal dysphagia. Mann-Whitney test and Fisher's test were used for statistical analysis. Results Stroke (OR=2.93 p=0.02), malnutrition (OR=2.89 p=0.02) and prolonged orotracheal intubation (OR=3.94 p=0.02) were statistically significant predictors for oropharyngeal dysphagia within this population. Age below 80 years was not significant (p=0.06), but within octogenarians, significance was found (p=0.033). Conclusion Stroke, malnutrition, prolonged orotracheal intubation and age > 80 years are predictive risk factors for oropharyngeal dysphagia in adult population with cardiovascular diseases.


Introduction
Cardiovascular disease is the leading cause of mortality worldwide. 1,2 Among its treatments, there is a clinical and/or a surgical option, often requiring prolonged hospitalization. Oropharyngeal dysphagia incidence in the population with cardiovascular disease varies from 2.7% to 51%, 3,4 and most studies have investigated this population within the postoperative period. 5,6 Regardless of the underlying disease, oropharyngeal dysphagia may be associated with several conditions of hospitalized patients and other clinical conditions associated with cardiovascular disease. 7,8 General evaluation of hospitalized patients includes nutritional status. Many may present unintentional weight loss due to malnutrition and low muscle strength, increasing the risk of developing oropharyngeal dysphagia. In addition, malnutrition is a frequent complication, as a result of specific difficulties on swallowing, compromising caloric intake levels. 9 Some studies proposed the evaluation of nutritional status to predict the risk of dysphagia due to the significant association between these two conditions, in older adults. 10 Malnutrition was also recently considered an independent predictor for dysphagia in population with heart failure. 11,12 Potential risk factors for oropharyngeal dysphagia in cardiovascular disease populations are: advanced age, 13 prolonged orotracheal intubation (OTI) 14,15 and neurological diseases, such as stroke. OTI in cardiac surgery was considered a potential risk to increase the degree of swallowing impairment, 4 not only due to the surgical procedure, but also the clinical and respiratory decompensation . As for stroke, oropharyngeal dysphagia prevalence is high and, although widely studied, 16,17 it is rarely associated to the population with cardiovascular disease. 18 The conditions described above have already been identified as risk factors for oropharyngeal dysphagia.
However, in cardiovascular disease, most previous studies include individuals in postoperative period only 5,6,14,15,19   To analyze predictive risk factors for oropharyngeal dysphagia, parameters were stroke, nutritional status (malnourished, eutrophic and obese), age and OTI time equal to or greater than 48 hours.

Results
Mann-Whitney's test and Fisher's test were used for the statistical analysis of results; and odds ratio statistics (O.R) for categorical data analysis.
Univariate and multivariate were used to analyze risk factors associated with dysphagia. Table 2 shows that 46% of the individuals had oropharyngeal dysphagia and, among these, 58.7% were moderate level. Table 3 shows that 35% of patients were malnourished, 26% had stroke, 39% had prolonged intubation and 82% were over 60 years old.

Discussion
Investigation about oropharyngeal dysphagia in population with cardiovascular disease is outnumbered when compared to other underlying diseases.
Prevalence within literature varies from 2.7% to 51%, which may be related to the method used by each study in the investigation of dysphagia. 3,4 In this study, 46% of individuals with cardiovascular Our findings corroborate with studies which show that stroke is a clinical condition strongly associated with dysphagia. 17 The variable incidence in this population is due to the location and extent of the lesion, as well as different investigation methods used, with some studies reporting up to 90% incidence. 22 Thus, the presence of oropharyngeal dysphagia in cardiopathy population is closely related to the comorbidity of stroke, whether or not it is associated with surgery. The generalization of dysphagia in cardiopathy populations deserves further discussion.
Another very important and significant clinical condition in this study was malnutrition. At hospital admission, malnutrition ranges from 20% to 60% and may increase even more in patients with prolonged hospitalizations for clinical and surgical treatment, with a higher incidence among elderly, due to other risk factors associated with this population. 23,24 According to literature, aging is responsible for the reduction of caloric intake and progressive weight loss, due to catabolic state related to heart failure. Thus, many  Age was not a significant factor associated with dysphagia in this study, which can be explained by the fact that sample is predominantly made of the older people, as aging is already considered a risk factor for the cardiovascular diseases development (p=0.033).
This corroborates with the literature, which states that the progressive physiological aging of structures involved in swallowing process, associated with other comorbidities such as malnutrition, cardiovascular disease, stroke and prolonged hospitalizations negatively impact swallowing, generating risk for oropharyngeal dysphagia. 13 Long-term orotracheal intubation, significant in this study when exceeding 5 days and a tracheostomy tube, is considered a predictive risk factor for dysphagia, frequently cited as the cause of it in population submitted to heart surgery. Furthermore, it is extremely important to consider intubation not only within surgical context, but also in patients with cardiopathy hospitalized for clinical treatment, as they may need long periods of intubation. 4,18,26,27 The present study has its limitations.It was not possible to categorize possible cardiovascular clinical alterations, as well as the type of cardiac surgery, considering the variability of the sample. In addition, extracorporeal circulation time, the need for transesophageal echocardiography, and associations with other comorbidities such as dyslipidemias, COPD, among others, cited as risk factors for dysphagia in this population, were not analyzed. 8,18 Another limitation was the method use to evaluate swallowing, since clinical protocols have 73% to 98% accuracy. 28