Gastrointestinal Symptoms in Elderly Hemodialysis Patients

Aim: Gastrointestinal symptoms are common in patients with end-stage renal disease undergoing renal replacement therapy. The aim of this cross-sectional study was to determine the prevalence and diversity of gastrointestinal symptoms in elderly hemodialysis patients. Methods: Elderly patients (>75 years of age) of four outpatient hemodialysis service centers were given a questionnaire to complete which was previously validated and designed to measure the occurrence of gastrointestinal symptoms within the last six months. An interview with a nephrologist was completed at the same time. Results: A total of 112 patients responded (67 females, 45 males) to the questionnaire. Our study revealed a high prevalence of gastrointestinal symptoms in elderly patients. Ninety-four percent of elderly dialysis patients had at least one of the following chronic gastrointestinal symptoms: dyspeptic symptoms (especially bloating) was reported in 53%, chronic constipation was reported in 42%, pyrosis in 25% and abdominal pain in 22% of the patients. Thirty-eight percent had loss of appetite and 14% had chronic diarrhoea. Patients were moderately/severely bothered by symptoms in up to 63% of cases. Nausea and vomiting were the least prevalent symptoms. There was no significant statistical difference between the severity of symptoms by gender (p=0.483). Diabetes mellitus was not associated with more gastrointestinal symptoms (p=0.662). Conclusion: The prevalence of gastrointestinal symptoms is high in elderly dialysis patients and these symptoms cause a major health burden in their daily life. Our study showed no significant relationship between the severity of gastrointestinal symptoms and gender. Diabetic patients showed no substantial rise in the amount or severity of gastrointestinal symptoms as compared to non-diabetic patients.


Introduction
Gastrointestinal symptoms are widespread in patients undergoing maintenance hemodialysis and are a major cause of morbidity [1][2][3][4][5]. These symptoms are more common in older adults because of changes associated with aging, comorbidities such as diabetes, and medications they have to take. Delayed motility, decrease in gastric secretion, and decreased absorption in the elderly may be responsible for gastrointestinal symptoms [1,6,7].

Methods
We included all elderly hemodialysis patients older than 75 years who had been receiving dialysis for at least six months in four hemodialysis centers in Istanbul, Turkey. The severity of gastrointestinal symptoms was determined by a patient administered gastrointestinal symptoms questionnaire, which divided patients into three categories: mild, moderate, and severe.
The study was conducted through a face-to-face interview with a nephrologist to ensure that patients understood the questions.
Details on co-morbid conditions, medications and duration of dialysis were retrieved from medical notes. Patients diagnosed with a gastrointestinal disease, infectious illness, malignancies and who were hospitalized in the last 3 months were excluded.

Statistical Analysis
Data were coded and entered into the Statistical Package for Social Sciences program (SPSS) for analysis. Statistical analysis was performed with SPSS, version 23.0 (IBM, San Jose, CA, USA).
Comparisons were made between female and male patients as well as diabetic and non-diabetic patients. Continuous variables were expressed as mean ± standard deviation and categorical variables were presented as absolute (number of participants) and relative frequencies (percentages). Continuous variables were compared using either Student's t-test, whereas the categorical variables were compared with Pearson's χ2 analysis test where appropriate. A significant difference was considered when p < 0.05.

Results
Clinically stable geriatric hemodialysis patients (older than 75 years old) who were dialysis outpatients were included in this crosssectional study. Diabetes mellitus (43%) and hypertension (37%) were the two primary causes of ESRD. Characteristics of the study population are shown in Table 1  Ninety-four percent of the patients on hemodialysis reported at least one gastrointestinal symptom. The most frequent symptoms were bloating and constipation, while vomiting was the least prevalent ( Figure 1).  We did not find any association between the amount of gastrointestinal symptoms and gender (p = 0.64) ( Table 2). There was no significant statistical difference between the severity of symptoms by gender (p=0.483) ( Table 3).
Patients with diabetes showed no significant difference in the prevalence and severity of gastrointestinal symptoms compared to non-diabetics. Diabetes mellitus was not associated with more gastrointestinal symptoms (p=0.73) ( Tables 4 & 5).     [12,13].
Our study revealed a high prevalence of gastrointestinal symptoms in geriatric patients, with abdominal bloating and constipation being more prevalent and severe. In our crosssectional study, the most common symptom experienced by elderly dialysis patients was abdominal bloating (53%). Bossola et al. [2] also found a high incidence of bloating in dialysis patients. In a meta-analysis, the prevalence of bloating in hemodialysis patients ranged between 8-45.2% [5]. Hemodialysis patients have to limit their intake of potassium-rich foods such as fruits, vegetables, and other fiber-rich foods, and constipation is a side effect of this kind of diet.
Yasuda et al. [14] showed that constipation was very common in hemodialysis patients compared to peritoneal dialysis patients.
Fluid restriction, sedentary lifestyle and medications such as phosphate binders, may contribute to constipation in hemodialysis patients [1,3]. Zuvela et al. [5] investigated gastrointestinal symptoms in a total of 5161 dialysis (3804 HD and 1507 PD) patients across 30 studies and found that constipation was one of the most common gastrointestinal symptoms. Constipation was the second most common and severe presenting gastrointestinal symptom among elderly hemodialysis patients in our cross-sectional study.
Malnutrition is also an important criterion in the prognosis of patients with chronic renal failure and is associated with increased morbidity and mortality. In the elderly, malnutrition leads to additional decrease in quality of life [10,15]. Anorexia has been associated with malnutrition, poor quality of life, depression, greater hospitalization rates, and an increase in mortality [16].
Our study showed a high prevalence of anorexia in dialysis patients (38%

Conclusions
The current study showed that elderly patients on hemodialysis have a high prevalence of gastrointestinal symptoms, with abdominal bloating and constipation being more prevalent and severe. Further evaluation in a larger population of elderly dialysis patients is needed.
studies should focus on the type of diet and medications to better comprehend the effects of these symptoms on elderly dialysis patients.