|Year : 2019 | Volume
| Issue : 1 | Page : 54-60
Comparison of endoscopic findings in Egyptian and Indian patients: a retrospective cohort
Essam A Hassan1, Tarek I Ahmed2, Sanjay Rajput3
1 Tropical Medicine department, Faculty of Medicine, Fayoum University, Fayoum, Egypt
2 Internal Medicine Department, Faculty of Medicine, Fayoum University, Fayoum, Egypt
3 Ansh Clinic, Ahmedabad, Gujarat, India
|Date of Submission||30-Dec-2018|
|Date of Acceptance||25-Mar-2019|
|Date of Web Publication||12-Sep-2019|
Tarek I Ahmed
Department of Internal Medicine, Fayoum University, Fayoum 63514
Source of Support: None, Conflict of Interest: None
Aims Esophagogastroduodenoscopy is the commonest diagnostic procedure performed to evaluate upper gastrointestinal tract. However, there are limited data on the differences in endoscopic findings in different populations. Therefore, we conducted this study to compare the frequencies of endoscopic findings in two different populations.
Patients and methods We used a large endoscopic database to retrieve the data of patients who underwent esophagogastroduodenoscopy at Fayoum University Hospital, Egypt and Ansh Clinic, Ahmadabad, India in the year of 2016.
Results A total of 7107 patients were included in the final analysis: 5527 from India and 1580 from Egypt. Indian patients were more likely to present with normal finding (54.6 vs. 22.7%, P<0.001), whereas Egyptian patients were presenting with varices more commonly (49.5 vs. 15.9%, P<0.001). The Egyptian cohort showed a high frequency of grades I and III gastroesophageal reflux disease, whereas the Indian cohort revealed higher grades I and II varices (P<0.001). Gastritis was more common in Indian patients (67.2 vs. 35.2%, P>0.001). Overall, varices are most common in older male patients (>20 years), gastroesophageal reflux in males, and gastritis in females.
Conclusion Further research is needed to validate our findings regarding the effect of age and sex on the frequency of endoscopic findings.
Keywords: duodenum, endoscopy, esophagus, stomach
|How to cite this article:|
Hassan EA, Ahmed TI, Rajput S. Comparison of endoscopic findings in Egyptian and Indian patients: a retrospective cohort. Al-Azhar Assiut Med J 2019;17:54-60
|How to cite this URL:|
Hassan EA, Ahmed TI, Rajput S. Comparison of endoscopic findings in Egyptian and Indian patients: a retrospective cohort. Al-Azhar Assiut Med J [serial online] 2019 [cited 2020 Jun 2];17:54-60. Available from: http://www.azmj.eg.net/text.asp?2019/17/1/54/266731
| Introduction|| |
The symptoms of upper gastrointestinal tract (GIT) diseases are very common ,. Known as upper gastrointestinal endoscopy, esophagogastroduodenoscopy (EGD) yields an excellent modality for evaluating the underlying pathologies by enabling the visual inspection of the mucosa of the GIT (esophagus, stomach, and duodenum). Standard diagnostic indications for EGD include assessment of upper gastrointestinal symptoms that persist despite an appropriate trial of therapy, upper abdominal symptoms associated with other symptoms or signs suggesting structural diseases or deformity (e.g. anorexia and weight loss), or new onset of dyspepsia in patients older than 50 years of age . Dysphagia has been reported to significantly worsen the quality of life in affected individuals, with patients reporting panic, stress, and anxiety about eating, as well as developing depression ,.
There have been multiple studies conducted in Egypt and India to estimate the prevalence of different upper endoscopic findings in patients complaining of dysphagia. A cross-sectional study conducted in Egypt to determine the frequency of endoscopic findings in patients presenting with dysphagia showed that gastroesophageal reflux disease (GERD) is the most common endoscopic finding followed by esophageal stricture, esophageal mass, and normal endoscopic findings . On the contrary, in a study conducted on Indian patients presenting with dyspepsia, gastritis was the most common endoscopic finding followed by gastric ulcer . Another study conducted in India revealed that esophageal erosion was the most common finding in the esophagus, whereas gastritis was the most common findings in the stomach, and duodenitis has the highest prevalence of duodenal endoscopic findings . To the best of our knowledge, there has been no study conducted to address the differences in endoscopic findings in these populations and whether these differences are significant or not as well as assess the factors that could attribute or even account for such differences.
Moreover, there is no or little, if any, data of the relative prevalence rates of various endoscopic findings and whether or not they differ according to the patients’ demographics, or according to sex and different age groups. Therefore, we conducted this study to estimate the overall prevalence rates of various endoscopic findings in the Egyptian and Indian cohorts and to determine the frequencies of such findings according to sex and age groups.
| Patients and methods|| |
This retrospective comparative study was conducted at two different health centers: Fayoum University Hospital, Egypt and Ansh Clinic, Ahmadabad, India. Informed consent was obtained from all of the study participants. Our inclusion criteria were all patients referred to endoscopy unit by gastroenterology specialists for doing endoscopy during the year of 2016. Participants’ demographic data and endoscopic findings were obtained from a large endoscopic database and revised for further incorporation in the study. A total of 7107 participants: 5527 Indian patients and 1580 Egyptian patients, who had undergone at least a single EGD during the study period for the indication of dysphagia, were included in the study, regardless of their sex or age.
Sociodemographic background of our participants was obtained, and the endoscopic evaluation was categorized according to the three structures: esophagus, stomach, and duodenum. Esophageal endoscopic findings were identified as normal, GERD, varices, mass, ulcer, stricture, polyp, and mixed (others). GERD and varices were furtherly assessed based on their grades (I, II, III, or IV). Gastric findings were grouped as normal, gastritis, portal hypertensive gastropathy (PHG), varices, mass, ulcer, vascular malformation, polyp, and mixed (others). Duodenal findings were identified as normal, duodenitis, atrophy, mass, ulcer, stricture, polyp, and mixed (others). The prevalence of these selected endoscopic findings was determined overall and also stratified by sex and age groups (≤20 or >20 years) in the two included populations (Egyptian and Indian). Before conducting the study, ethical approval was obtained from the corresponding Research Ethics Committee, Institutional Review Board (IRB) of the two health centers.
All relevant data were collected, entered into Microsoft Access, and coded to facilitate further data manipulation. The analysis was performed using SPSS, version 18 software (Milton, QLD, Australia). Frequency and percentages were calculated for categorical variables like sex and common EGD findings. Mean±SD were calculated for quantitative variables like age. Categorical variables were compared using the χ2 test. Student’s t test was used to compare different numerical variables (quantitative). A P value less than or equal to 0.05 was considered statistically significant.
| Results|| |
The records of 7107 patients undergoing EGD) in the year of 2016 (5527 in India and 1580 in Egypt) were reviewed and included in the final analysis. Evaluation of these patients was performed at three levels: esophageal findings, gastric findings, and duodenal findings. The mean age of Indian population was 45.4 (SD=17.3), whereas the mean age of the Egyptian population was 46.5 (SD=15.5). Males were predominant in both populations: Indian and Egyptian (60.3 and 56.9%, respectively). Demographic characteristics of each population are presented in [Table 1].
|Table 1 Comparisons of demographic characteristics in different study groups|
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At the level of esophageal evaluation, the Indian population presented with normal endoscopy results as the most common finding (54.6%), followed by mixed findings (39.6%) and esophageal varices (15.9%). On the contrary, the Egyptian population presented with esophageal varices (49.5%) as the most common endoscopic finding followed by normal (22.7%) and mixed findings (22.6%). Upon comparison of both populations, Indian patients were more likely to present with normal endoscopic picture compared with Egyptian patients (54.6 vs. 22.7%, P<0.001), whereas Egyptian patients were more likely to present with esophageal varices (49.5 vs. 15.9%, P<0.001). Meanwhile, Indian patients were more likely to present with esophageal varices of grade I (49.1 vs. 27.3%, P<0.001) and grade II (50.2 vs. 49.6%, P<0.001). Egyptian patients were more likely to present with grade I (74.5 vs. 50.2%, P<0.001) and grade III (5.5 vs. 0%, P<0.001) GERD, whereas Indian patients showed higher rates of grade II GERD (49.8 vs. 20%, P<0.001). Other findings did not differ substantially between both cohorts ([Table 2]). Injection was the most commonly used approach to manage varices in the Indian population, whereas ligation was the most common method used in the Egyptian population.
|Table 2 Comparisons of esophageal endoscopic finding in different study groups|
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At the level of gastric evaluation, regarding the Indian population, gastritis was the most common finding followed by mixed findings and PHG (67.2, 58.4, and 14.2%, respectively). On the contrary, Egyptian patients had normal endoscopic picture as the most common finding followed by gastritis and PHG (38.9, 35.2, and 13.3%, respectively). Upon comparing both populations, Egyptian population was more likely to present with normal finding (38.9 vs. 12.5%, P <0.001), whereas Indian population was more likely to present with gastritis (67.2 vs. 35.2%, P <0.001). Other findings did not differ substantially between both cohorts ([Table 3]).
|Table 3 Comparisons of stomach endoscopic finding in different study groups|
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At the level of duodenum evaluation, normal finding was the most common presentation followed by duodenitis in the entire cohort − both populations. However, Egyptian patients were slightly more likely to present with duodenitis compared with Indian patients (11.9 vs. 10.8%, P=0.001). Other findings are comparable in both cohorts (Supplementary 1).
According to different age groups, patients above 20 years old were more likely to present with esophageal varices in both populations (Indian and Egyptian) (16.6 vs. 5.5%, 49.7 vs. 46.3%, respectively). Indian patients above 20 years old were more likely to present with GERD compared with younger matches (9.8 vs. 2.6%, P<0.001). On the contrary, Egyptian patients above 20 years old were less likely to present with such finding − GERD (15 vs. 30.6%, P=0.001). Age groups showed no statistical significance in grades of varices and GERD in the Indian population. On the contrary, regarding Egyptian population, more than 20 years old patients we more likely to present with grade I GERD (78.4 vs. 50%, P=0.004), whereas younger patients (≤20 years) were more likely to present with grade II GERD (40 vs. 16.8%, P=0.004) ([Table 4] and [Table 5]).
|Table 4 Comparisons of esophagus endoscopic findings in different age groups among Indian patients|
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|Table 5 Comparisons of esophagus endoscopic finding in different age groups among Egyptian patients|
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Regarding gastric findings, Indian patients were more likely to present with PHG at an older age (>20 years) (14.8 vs. 5.3%, P<0.001), whereas they are more likely to present with gastric vascular malformation (1.4 vs. 0.3%, P<0.001) at a younger age (≤20 years). Moreover, older Indian patients (>20 years) were more likely to present with duodenitis and duodenal ulcer. On the contrary, different age groups did not reveal any significant difference in gastric and duodenal findings in the Egyptian population (Supplementary 2 and 3).
Sex differences in endoscopic findings revealed that males were more likely to present with varices and GERD in both Indian and Egyptian populations (P<0.001). However, female patients were more likely to present with gastritis in both cohorts (P<0.001). Regarding duodenal findings, male Indian patients were more likely to present with duodenitis and duodenal ulcer (P<0.001). Grades of GERD and esophageal varices revealed no significant differences in both sexes (Supplementary 4, 5, 6, 7, 8, and 9).
| Discussion|| |
Known as upper endoscopy, EGD is the most common initial diagnostic procedure carried out in the evaluation of esophageal dysphagia. It allows direct and maximal visualization of the entire esophagus and tissue acquisition via biopsy . Multiple studies have been conducted to establish different endoscopic findings for patients presenting with dysphagia ,. There are, however, no or little, if any, data on the relative prevalence rates of different endoscopic findings in patients presenting with dysphagia and whether or not these findings change according to the patient’s demographics. Therefore, we aimed to address the differences in the prevalence rates according to different age groups and sex in two completely different populations.
Our results showed that normal was the most common esophageal endoscopic finding in the Indian cohort followed by mixed findings (others) and varices. On the contrary, varices were the most common presentation in the Egyptian cohort, followed by normal and mixed findings. Meanwhile, another study conducted in Egypt showed that normal endoscopic picture was the third common finding with a percentage of 15.7% . Inconsistently, Gilani et al.  reported that normal finding had a high rate of 32.5%. Such differences may be owing to geographic and genetic variations and may also be owing to differences in sample sizes. On comparison of our two populations, Egyptian patients were more likely to present with varices, whereas Indian patients were more likely to present with normal endoscopic finding. Egypt is known to have the highest prevalence of hepatitis C virus (HCV) infection (>10% of the general population) . Going in line with the literature, we hypothesize that such high rates of esophageal varices in our Egyptian cohort could be HCV-induced varices; however, this finding needs further confirmation as we do not know the HCV background of our patients . Moreover, alcohol consumption, which is known to increase the risk of alcoholic cirrhosis and subsequent esophageal varices, could have played a role .
Indian patients in our study had significantly higher rates of esophageal varices grades I and II compared with Egyptian peers. It is possible that such differences could be related to interobserver variability in the grading of varix size which is known to differ by 10–15% . Alternatively, the reproducibility of estimating esophageal varices in a given individual owing to technical factors of insufflating the esophagus could have also played a role. Our Indian cohort was more likely to present with grade II GERD, whereas the Egyptian cohort was more likely to present with grades I and III GERD. The reason behind this difference remains controversial; however, it has been proposed that obesity, NSAID, and Helicobacter pylori infection are strong risk factors for differences in GERD grades . The increased amount of fat in the abdomen of obese patients leads to increase in the pressure in the stomach and more relaxation of the sphincter, thus promoting GERD formation ,. NSAIDs may interfere with esophagogastric junction function and impair the protective mechanisms against the acid . We have not reviewed the full history of our participants, so this point needs to be furtherly addressed.
Compared with the Egyptian cohort, Indian patients were more likely to present with gastritis. Gastritis is a common medical disorder in India with an incidence of approximately three in 869 . Smoking, alcohol consumption, tobacco use, spicy food, drugs, and stress are all risk factors for gastritis. Our Indian population could have had worsened conditions, increased stress, and bad life habits, which could explain their high rate of gastritis . However, this needs further assessment. On the contrary, Egyptian patients were more likely to present with duodenitis. It has been postulated that the presence of endoscopic finding of duodenitis may appear from H. pylori infection . Multiple studies conducted in Egypt have reported a prevalence rate of H. pylori infection of 69.4% in adults and 72.38% in children ,. Based on the assumption that our Egyptian patients had high H. pylori infection rates, this could possibly explain why they had higher rates of duodenitis. However, we did not know the H. pylori status of our patients; therefore, further investigations by larger prospective studies would be helpful in understanding the underlying cause and attributable factors of duodenitis.
The relative prevalence of endoscopic findings in our study according to different age groups showed that Indian patients more than 20 years old had significantly higher rates of GERD compared with younger peers. On the contrary, Egyptian patients of 20 years or less were more likely to present with GERD compared with older peers. Noteworthy, developing GERD at an earlier age has been shown to increase the risk of esophageal adenocarcinoma . A national multicenter study conducted in China stated that the prevalence of GERD increases with age . The association between GERD and age remains controversial. Several studies observed a positive relationship ,,, whereas other studies detected an inverse association , or a lack of relationship ,,,,,. Many explanations have been proposed. Obesity has been showed to increase the risk of GERD , whereas BMI has been reported to be directly linked to increased risk of GERD whether the patient was of normal weight or overweight . These factors should put into consideration in future work. Overall, in both cohorts, patients of more than 20 years had significantly higher prevalence rates of esophageal varices.For the entire cohort, our analysis revealed that males had significantly higher prevalence rates of GERD and esophageal varices. This finding is incompatible to what has been reported by another study which stated that females had higher rates of GERD . Differences in lifestyle, diet, socioeconomic status, and comorbidity may account for such differences . Portal hypertension, as a leading cause of esophageal varices, has been known to be more common in males, explaining the high rates of varices in our male population . Overall, in our study, gastritis rates were significantly higher in female patients. A previous research revealed no significant difference in gastritis rates in both sexes . However, lifestyle changes, drugs (NSAIDs), stress, and life habits are well-known causative factors for gastritis and could possibly explain the differences in our findings from that in the literature .
The strengths of this study include the large sample size and the diverse practice sites that contributed data. Moreover, this study provides a comparison between two different nations with different feeding habits and different GIT symptoms, hence a better understanding of population-specific pathologies. However, we have encountered several limitations. Besides the retrospective design of our study, the database that we used did not provide a full detailed history of the patient’s status such as comorbidities, lifestyle, and habit to be able to fully evaluate the underlying cause of high gastritis, GERD, and varices rates. Therefore, further studies are required to address these limitations for further implication of our findings.
In conclusion, Egyptian patients were more likely to present with esophageal varices and duodenitis compared with Indian patients, whereas the Indian cohort was more likely to present with gastritis. Indians were more likely to have grade II GERD and grades I and II varices, whereas Egyptians were more likely to have grades I and III GERD. In both cohorts, varices have shown to be appear more frequently in the older age group (>20 years); however, GERD rate increased in the older Indian population, whereas it showed an increase in the younger Egyptian population (≤20 years). For the entire cohort, male patients were more likely to present with varices and GERD, whereas, female patients were more likely to present with gastritis.
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Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]