Comparison of electrogastrography findings in patients with dyspepsia with and without type 2 diabetes mellitus

Abstract

BACKGROUND

Dyspepsia encompasses a wide range of high-prevalence upper gastrointestinal symptoms, especially in patients with type 2 diabetes mellitus (T2DM) owing to diabetic autonomic neuropathy. Despite its disruption to daily life, limited studies have compared patients with dyspepsia with and without T2DM, largely due to high-cost, availability, and radiation exposure of the gold standard gastric emptying scintigraphy (GES). Although less accurate than GES, electrogastrography (EGG) examination is more affordable, non-invasive, and radiation-free instead, recording gastric myoelectrical activity to assess gastric motility dysfunction, and making it a promising preliminary evaluation tool for detecting gastric motility dysfunction.

AIM

To investigate gastric myoelectrical activity in patients with dyspepsia with and without T2DM using EGG.

METHODS

Clinical and demographic data of study participants were collected from August to December 2025 at Cipto Mangunkusumo National Hospital and Mitra Keluarga Hospital Kemayoran through consecutive sampling. Eligible subjects were patients who provided informed consent, had complete medical records, completed the Indonesian version of the Short-Form Leeds Dyspepsia Questionnaire, and underwent EGG recordings. Data were statistically analysed using SPSS version 26.0, including bivariate comparative analyses and multivariate analysis with robust variance estimation Poisson regression.

RESULTS

In total, 76 subjects (38 in each group) were included. Patients in the T2DM group were older (P = 0.001), predominantly obese (P = 0.006), and had higher rates of indigestion (P = 0.021) and bradygastria (P = 0.005). EGG results were similar across demographic characteristics (P > 0.05), while T2DM status remained independently associated with bradygastria in multivariate analysis. Compared with other forms of gastric myoelectrical activity, patients with T2DM had a higher likelihood of bradygastria (adjusted prevalence ratio: 1.739; 95%CI: 1.079-2.804; P = 0.023). Additionally, good glycaemic control (glycated haemoglobin of < 6.5%) in patients with T2DM was associated with milder dyspepsia (P = 0.036).

CONCLUSION

T2DM is significantly associated with bradygastria in patients with dyspepsia. Good glycaemic control is associated with milder dyspeptic symptoms in patients with T2DM.

Key Words: Type 2 diabetes mellitus; Dyspepsia; Electrogastrography; Gastrointestinal motility; Glycated haemoglobin

Core Tip: This study compared dyspepsia in patients with and without type 2 diabetes mellitus (T2DM) using electrogastrography (EGG). The results highlight the association between T2DM and gastric myoelectrical activity. While age, sex, and body mass index may act as confounding factors, T2DM was significantly associated with a higher prevalence of bradygastria on EGG findings. Furthermore, the severity of dyspeptic symptoms in T2DM was associated with glycaemic control. These findings demonstrate the potential role of EGG as a non-invasive preliminary evaluation tool for gastric motility abnormalities and provide further insight into the characteristics of dyspepsia in T2DM.

INTRODUCTION

Dyspepsia, a major upper gastrointestinal disorder, affects approximately 16%-30% of the population[1,2]. According to the Rome IV Criteria, dyspepsia can be categorized into postprandial distress syndrome and epigastric pain syndrome. Postprandial distress syndrome is characterized by postprandial fullness and early satiety, while epigastric pain syndrome is characterized by epigastric pain and heartburn[3]. Based on aetiology, dyspepsia may be classified as organic, functional, or uninvestigated. Several risk factors have been identified, such as older age, female sex, Helicobacter pylori(H. pylori) infection, psychological factors, diet, nonsteroidal anti-inflammatory drug use, gastric motility dysfunction, and smoking[3-6]. Therefore, consideration of patient risk factors and demography is essential in the clinical approach to dyspepsia. This is particularly relevant in patients with type 2 diabetes mellitus (T2DM), in whom the risk of dyspepsia is higher than in the general population[7].

In T2DM, chronic hyperglycaemia due to insulin resistance and/or reduced insulin secretion causes long-term damage to multiple target organs, including the heart, kidney, nervous system, and eyes. In the gastrointestinal system, T2DM affects gastric motility and contributes to the development of gastroparesis[7-9]. As gastric emptying slows, patients may experience prolonged postprandial fullness, nausea, vomiting, and uncontrolled or fluctuating blood glucose levels[10]. The higher prevalence of dyspepsia in patients with T2DM is associated with diabetic autonomic neuropathy, which impairs gastric motility through damage to the vagus nerve. In addition, chronic hyperglycaemia may disrupt hormonal balance, impair gastric smooth muscle activity, and worsen gastric motility dysfunction[7].

Several methods to evaluate gastric motility are available, with gastric emptying scintigraphy (GES) considered the gold standard for evaluation of gastric emptying time. However, GES has remained costly and time-consuming, and requires exposing the patient to radiation, which limits its routine use in Indonesia. In contrast, electrogastrography (EGG) is a non-invasive method used to determine gastric motility dysfunction by detecting abnormal gastric myoelectrical activity. The use of EGG offers greater convenience and patient comfort; however, its accuracy and result interpretation remain limited because it does not directly measure gastric muscle contractility or gastrointestinal pressure. Despite these limitations, EGG may be useful for the evaluation of dyspepsia, especially in patients with T2DM[11,12]. To our knowledge, no previous study has evaluated EGG findings among patients with dyspepsia with and without T2DM in Indonesia.

Through this study, we aimed to evaluate the potential of EGG as a preliminary evaluation tool for dyspepsia in patients with and without T2DM by examining gastric electrical activity and exploring its potential implications for improving therapeutic approaches.

MATERIALS AND METHODS

Data and participants

This cross-sectional comparative study was conducted in Jakarta, Indonesia, from August 1, 2025 to December 31, 2025, at two tertiary hospitals: Cipto Mangunkusumo National Hospital and Mitra Keluarga Kemayoran Hospital. The study was performed in accordance with the principles of the Declaration of Helsinki and was approved by the health ethics committees of both hospitals before the commencement of the study. Participants were recruited consecutively to maximize recruitment feasibility and reduce the risk of bias in sampling. All participants provided written informed consent prior to participation. Primary data were obtained from EGG recordings and questionnaires, while secondary data were collected from participants’ medical records (Figure 1).

Figure 1 Research process. EGD: Esophagogastroduodenoscopy; T2DM: Type 2 diabetes mellitus.

Inclusion and exclusion criteria

The inclusion criteria for this study required patients to provide informed consent before enrolment. Eligible participants were adults aged ≥ 18 years who had been diagnosed with dyspepsia and had undergone upper gastrointestinal endoscopy within 8 weeks before enrolment. The diagnosis of dyspepsia was based on the American College of Gastroenterology/American Gastroenterological Association criteria, which included patients who have experienced symptoms for at least 1 month and presented with at least one of the following symptoms: Epigastric pain, epigastric burning, early satiety, and/or postprandial fullness. Patients in the T2DM group had a confirmed diagnosis of T2DM and were either receiving ongoing therapy for T2DM or had a glycated haemoglobin (HbA1c) level of > 6.5% in the previous 3 months. Patients in the non-T2DM group had no prior diagnosis of T2DM or other types of DM and had fasting blood glucose < 200 mg/dL or HbA1c < 6.5%.

To minimize potential bias, patients with organic gastrointestinal diseases, including peptic ulcer disease, oesophageal stricture, oesophageal varices, severe gastric erosion, gastric polyps, and duodenal ulcers, were excluded [as assessed by esophagogastroduodenoscopy (EGD) within 2 months before the EGG testing]. Patients with cancer, other severe comorbidities, or a history of gastrointestinal surgery were also excluded. In addition, patients presenting with dyspepsia accompanied by one or more alarm symptoms (unintentional weight loss, anaemia, recurrent vomiting, hematemesis, melaena, dysphagia, or family history of gastrointestinal cancer) and those who were pregnant or breastfeeding were excluded. Moreover, patients with incomplete data or poor compliance and those who had used medications that could affect gastric motility, including nonsteroidal anti-inflammatory drugs, prokinetics, anticholinergics, opioids, GLP-1 receptor agonists, and/or antidepressants within 7 days before EGG testing were also excluded.

Study variables

In this study, T2DM status was considered an independent variable, while EGG results were the primary dependent variable. The Short-Form Leeds Dyspepsia Questionnaire (SF-LDQ) score, dyspepsia severity, and predominant symptoms were analysed as secondary dependent variables. Potential covariates, including age, sex, and body mass index (BMI) according to the Asia-Pacific classification, were also analysed to control for potential confounding factors.

Outcome

Subjects were grouped according to T2DM status into the T2DM group and the non-T2DM group. EGG results were classified according to the 3CPM (Sparks Glencoe, MD, United States) elastography system manufacturer’s criteria for the dominant frequency range, defined in cycles per minute (cpm): Bradygastria (< 2.5 cpm), normogastria (2.5-3.75 cpm), and tachygastria (> 3.75 cpm)[13]. The Indonesian version of SF-LDQ was used to evaluate dyspepsia severity (scores 1-8: Mild, 9-15: Moderate, 16-32: Severe) and predominant symptoms (heartburn, indigestion, regurgitation, or nausea)[14].

Sample size

A minimum of 30 participants per group was needed for this study, based on a sample size calculation for two independent groups with a 95%CI and 80% statistical power. This calculation was performed using the standard formula for comparing two proportions:

,

n₁: Sample size of non-T2DM group; n₂: Sample size of T2DM group; P₁: Expected proportion of outcome in non-T2DM group; P₂: Expected proportion of outcome in T2DM group; Q₁ = 1 - P₁; Q₂ = 1 - P₂; Z_α/2: Standard normal value for significance (equals to 1.96 for P < 0.05 significance cut-off); Z_β: Standard normal value for statistical power (equals to 0.84 for 80% statistical power).

The estimated prevalence of dyspepsia in the two groups was derived from previous studies, which reported rates of 6.78% in the non-T2DM group and 36% in the T2DM group[15,16].

Statistical analyses

The data were cleaned and subsequently analysed using SPSS version 26.0 (IBM Corp., Armonk, NY, United States). Univariate analysis was conducted to assess data distribution and homogeneity and to describe the characteristics of the study participants. Bivariate analysis between the two groups was conducted based on data distribution; for normally distributed numeric variables, the independent t-test was used. Ordinal and nominal variables were analysed using the χ² test or the Fisher-Freeman-Halton test when the assumptions for the χ² test were not met. For comparisons involving more than two groups, one-way analysis of variance was used for numeric variables, whereas ordinal and nominal variables were analysed using the χ² test. When the assumptions for the χ² test were not satisfied, Fisher’s exact test was applied. The prevalence ratio (PR) was calculated with robust variance estimation Poisson regression to address the relationship between T2DM and gastric myoelectrical activity in patients with dyspepsia. Multivariate analysis was conducted by incorporating theoretically relevant covariates that had yielded a P < 0.25 in the bivariate analysis into a robust variant estimation Poisson regression model to minimize overestimation.

RESULTS

Demographic and clinical characteristics of study subjects

A total of 76 participants were recruited in this study, with 38 participants each in the T2DM and non-T2DM groups. The characteristics of the study participants are presented in Table 1. The mean age of the participants was 49.85 years, and 60.53% of them were female. The two groups differed significantly in age distribution. The T2DM group consisted predominantly of older participants, with 73.68% aged ≥ 50 years, whereas the majority of participants in the non-T2DM group were younger than 50 years of age (71.05%). However, the sex distribution between the two groups was similar. The majority of the participants were obese, while only 11 participants (14.47%) had a normal BMI.

Table 1 Baseline characteristics of study participants and bivariate analysis of study cohorts, n (%)/mean ± SD.

Characteristics	Overall	T2DM, n = 38	Non-T2DM, n = 38	P value
Age (year)	49.855 ± 15.851	56.736 ± 14.128	42.973 ± 14.574	< 0.001
18-49	37 (48.7)	10 (26.3)	27 (71.0)	0.001
≥ 50	39 (51.3)	28 (73.7)	11 (29.0)
Sex				0.814
Male	30 (39.5)	16 (42.1)	14 (36.8)
Female	46 (60.5)	22 (57.9)	24 (63.2)
BMI Asia-Pacific category				0.006
Underweight	5 (6.6)	3 (7.9)	2 (5.3)
Normal	11 (14.5)	2 (5.3)	9 (23.7)
Overweight	15 (19.7)	3 (7.9)	12 (31.5)
Obesity I	29 (38.2)	18 (47.4)	11 (29.0)
Obesity II	16 (21.1)	12 (31.5)	4 (10.5)
HbA1c (%)	6.95 (2.2)	6.95 (2.2)
SF-LDQ score	16.408 ± 6.907	15.157 ± 6.680	17.657 ± 6.991	0.115
Dyspepsia severity				0.097
Mild	13 (17.1)	8 (21.1)	5 (13.2)
Moderate	23 (30.3)	14 (36.8)	9 (23.7)
Severe	40 (52.7)	16 (42.1)	24 (63.2)
Dominant symptom				0.105
None	1 (1.3)	0 (0)	1 (2.6)
Heartburn	13 (17.1)	4 (10.5)	9 (23.7)
Indigestion	34 (44.7)	22 (57.9)	12 (31.5)
Regurgitation	12 (15.8)	4 (10.5)	8 (21.1)
Nausea	16 (21.1)	8 (21.1)	8 (21.1)
EGG result				0.005
Bradygastria	47 (61.8)	30 (78.9)	17 (44.7)
Normogastria	18 (23.7)	5 (13.2)	13 (34.2)
Tachygastria	11 (14.5)	3 (7.9)	8 (21.1)

BMI: Body mass index; EGG: Electrogastrography; HbA1c: Haemoglobin A1c; SF-LDQ: Short-Form Leeds Dyspepsia Questionnaire; T2DM: Type 2 diabetes mellitus.

T2DM is significantly associated with abnormal gastric motility in dyspepsia

Bivariate analysis comparing patients with dyspepsia in the T2DM and non-T2DM groups showed that age and BMI category were significantly associated with T2DM status. The analysis also indicated that T2DM was associated with abnormal gastric motility based on EGG results (P = 0.005). However, T2DM status was not associated with differences in SF-LDQ scores or overall dyspepsia severity. Accordingly, the association measured with PR, as shown in Table 2, revealed that patients with both dyspepsia and T2DM had higher prevalence of bradygastria compared to other gastric myoelectrical forms (PR: 1.765; 95%CI: 1.195-2.606; P = 0.004) and lower prevalence of normogastria compared to other gastric myoelectrical forms (PR: 0.385; 95%CI: 0.152-0.973; P = 0.044).

Table 2 Prevalence ratio of different gastric myoelectrical activity in patients with dyspepsia, with and without type 2 diabetes mellitus, n (%).

Comparison	T2DM, n = 38	Non-T2DM, n = 38	PR (95%CI)	P value
Bradygastria vs others	30 (78.9)	17 (44.7)	1.765 (1.195-2.606)	0.004
Normogastria vs others	5 (13.2)	13 (34.2)	0.385 (0.152-0.973)	0.044
Tachygastria vs others	3 (7.9)	8 (21.1)	0.375 (0.108-1.307)	0.124

PR: Prevalence ratio; T2DM: Type 2 diabetes mellitus.

In contrast, Table 3 shows that none of the demographic covariates associated with the EGG findings significantly. The EGG results were also not associated with dyspepsia symptoms or severity significantly. Multivariate analysis (Tables 4 and 5) further demonstrated an association between T2DM and bradygastria. Covariate adjustment showed that patients with dyspepsia and T2DM are more likely to exhibit bradygastria compared to other gastric myoelectrical forms (adjusted PR: 1.739; 95%CI: 1.079-2.804; P = 0.023).

Table 3 Bivariate analysis of electrogastrography results, n (%)/mean ± SD.

Characteristics	Bradygastria, n = 47	Normogastria, n = 18	Tachygastria, n = 11	P value
Age (years)	51.553 ± 16.241	48.277 ± 15.461	45.181 ± 14.919	0.439
18-49	21 (44.7)	8 (44.4)	6 (54.5)	0.830
≥ 50	26 (55.3)	10 (55.6)	5 (45.5)
Sex				0.376
Male	22 (46.8)	3 (16.7)	5 (45.5)
Female	25 (53.2)	15 (83.3)	6 (54.5)
BMI Asia-Pacific category				0.084
Underweight	3 (6.4)	1 (5.6)	1 (9.1)
Normal	3 (6.4)	4 (22.2)	4 (36.4)
Overweight	8 (17.0)	6 (33.3)	1 (9.1)
Obesity I	22 (46.8)	5 (27.8)	2 (18.2)
Obesity II	11 (23.4)	2 (11.1)	3 (27.3)
T2DM status				0.005
Non-T2DM	17 (36.2)	13 (72.2)	8 (72.7)
T2DM	30 (63.8)	5 (27.8)	3 (27.3)
SF-LDQ score	15.723 ± 6.199	17.611 ± 8.111	17.363 ± 7.966	0.550
Dyspepsia severity				0.519
Mild	8 (17.0)	2 (11.1)	3 (27.3)
Moderate	17 (36.2)	4 (22.2)	2 (18.2)
Severe	22 (46.8)	12 (66.7)	6 (54.4)
Dominant symptom				0.368
None	1 (2.1)	0 (0)	0 (0)
Heartburn	7 (14.9)	4 (22.2)	2 (18.2)
Indigestion	24 (51.1)	8 (44.4)	2 (18.2)
Regurgitation	5 (10.6)	4 (22.2)	3 (27.3)
Nausea	10 (21.3)	2 (11.1)	4 (36.4)

BMI: Body mass index; SF-LDQ: Short-Form Leeds Dyspepsia Questionnaire; T2DM: Type 2 diabetes mellitus.

Table 4 Multivariate analysis of electrogastrography results comparing bradygastria with other forms of gastric rhythms.

Variables	Adjusted PR (95%CI)	P value
T2DM	1.739 (1.079-2.804)	0.023
Age (years)
18-49	0.690 (0.437-1.090)	0.112
≥ 50	Reference group	1
BMI Asia-Pacific category
Underweight	1.088 (0.277-5.967)	0.826
Normal	0.550 (0.180-1.683)	0.295
Overweight	1.100 (0.546-2.216)	0.791
Obesity I	1.346 (0.868-2.088)	0.185
Obesity II	Reference group	1
SF-LDQ score	0.968 (0.914-1.026)	0.276
Dyspepsia severity
Mild	0.813 (0.352-1.878)	0.628
Moderate	0.964 (0.550-1.690)	0.899
Severe	Reference group	1

BMI: Body mass index; PR: Prevalence ratio; SF-LDQ: Short-Form Leeds Dyspepsia Questionnaire; T2DM: Type 2 diabetes mellitus.

Table 5 Multivariate analysis of electrogastrography results comparing normogastria with other form of gastric rhythms.

Variables	Adjusted PR (95%CI)	P value
T2DM	0.445 (0.164-1.207)	0.112
Age (year)
18-49	1.862 (0.761-4.555)	0.173
≥ 50	Reference group	1
BMI Asia-Pacific category
Underweight	1.162 (0.120-11.292)	0.245
Normal	1.897 (0.308-11.665)	0.897
Overweight	1.937 (0.375-9.994)	0.490
Obesity I	0.976 (0.213-4.471)	0.430
Obesity II	Reference group	1
SF-LDQ score	1.000 (0.878-1.140)	0.994
Dyspepsia severity
Mild	0.354 (0.044-2.859)	0.330
Moderate	0.657 (0.149-2.896)	0.579
Severe	Reference group	1

BMI: Body mass index; PR: Prevalence ratio; SF-LDQ: Short-Form Leeds Dyspepsia Questionnaire; T2DM: Type 2 diabetes mellitus.

Blood sugar control in T2DM association with dyspepsia severity

In the T2DM cohort, only 14 out of 38 participants had controlled blood sugar levels (HbA1C < 6.5%). Table 6 presents an explorative analysis of glycaemic control. Participants with controlled blood glucose were significantly more likely to experience milder symptoms (P = 0.036) compared with those who had uncontrolled blood glucose. In the uncontrolled group, the majority of participants experienced moderate (11/24 vs 3/14) to severe dyspepsia (11/24 vs 5/14).

Table 6 Bivariate analysis of glycaemic control, n (%)/mean ± SD.

Characteristics	Controlled blood sugar, n = 14	Uncontrolled blood sugar, n = 24	P value
Age (years)	60.357 ± 14.867	54.625 ± 13.548	0.943
18–49	3 (21.4)	7 (29.2)	0.715
≥ 50	11 (78.6)	17 (70.8)
Sex			1.000
Male	6 (42.9)	10 (41.7)
Female	8 (57.1)	14 (58.3)
BMI Asia-Pacific category			0.882
Underweight	1 (7.1)	2 (8.3)
Normal	1 (7.1)	1 (4.1)
Overweight	2 (14.3)	1 (4.1)
Obesity I	6 (42.9)	12 (50.0)
Obesity II	4 (28.6)	8 (33.3)
SF-LDQ score	14.214 ± 8.097	15.708 ± 5.820	0.513
Dyspepsia severity			0.036
Mild	6 (42.9)	2 (8.3)
Moderate	3 (21.4)	11 (45.8)
Severe	5 (35.7)	11 (45.8)
Dominant symptom			0.792
None	0 (0)	0 (0)
Heartburn	1 (7.1)	3 (12.5)
Indigestion	9 (64.3)	13 (54.2)
Regurgitation	2 (14.3)	2 (8.3)
Nausea	2 (14.3)	6 (25.0)
EGG result			1.000
Bradygastria	11 (78.6)	19 (79.2)
Normogastria	2 (14.3)	3 (12.5)
Tachygastria	1 (7.1)	2 (8.3)

BMI: Body mass index; EGG: Electrogastrography; SF-LDQ: Short-Form Leeds Dyspepsia Questionnaire.

DISCUSSION

Sample exclusion

During the sample recruitment process, we found 93 potential patients for this study. However, 9 of those patients did not complete the SF-LDQ questionnaire and parts of their demographic data were missing from the medical record; in addition, 1 patient fasted for more than 16 hours and was not willing to reschedule the EGG testing, which posed a risk for bias in their result (as the patient fasted much longer than the recommended fasting duration for EGG); and 7 patients had gastric polyps identified during the evaluation of their EGD results. Thus, only 76 patients were ultimately included in this study. Sensitivity analysis (Supplementary Table 1) indicated no significant difference (P > 0.05) of available baseline and dependent variables between those patients that were included and those that were excluded from the study.

Covariates in participants with dyspepsia with T2DM and without T2DM

In Asian populations, dyspepsia is predominantly characterized by the dysmotility-like subtype. The prevalence of dyspepsia ranges from 10% to 30%, with 21% of the population predicted to have uninvestigated dyspepsia[3]. In this study, the youngest participant was 22-year-old and the oldest was 85-year-old, indicating that dyspepsia can occur at any age, although it appears to be most prevalent in middle age (45–54 years). Consistent with findings from previous epidemiological studies, we observed a higher prevalence of dyspepsia among females in both the T2DM and non-T2DM groups[17,18]. Obesity was also highly prevalent, especially in the T2DM group (P = 0.006). A previous study conducted in Turkey reported that obesity affects dyspepsia through mechanisms related to gastrointestinal dysmotility. In contrast, a study from Japan reported that being underweight was associated with functional dyspepsia in females[19-21]. However, in our study, the BMI category was not significantly associated with abnormal gastric motility, as observed on EGG.

T2DM correlates with gastric motility dysfunction in dyspepsia

Although SF-LDQ scores and overall dyspepsia severity did not differ significantly between the two groups, we observed higher prevalence of indigestion as the predominant symptom in the T2DM group. A similar finding was reported by Bandyopadhyay and Kolatkar[22] in 2025 in an Indian population, in which dyspepsia severity among patients with and without T2DM, assessed using the Gastroparesis Cardinal Symptom Index, was similar. However, symptoms related to indigestion, including early satiety (P < 0.0001) and bloating (P = 0.005), were significantly more frequent in patients with T2DM. The authors also reported a significant increase in regurgitation (P = 0.029), which was not observed in our study[22].

An increased incidence of bradygastria in patients with T2DM compared with healthy individuals has been reported previously in Western countries[23-26]. In contrast, a preliminary study comparing patients with gastroesophageal reflux disease with DM (n = 10) and those without DM (n = 13) did not obtain significant differences in EGG findings between the two groups. In that study, patients with DM were found to have gastric autonomic dysfunction, while patients without DM were found to have abnormal 24-hour pH measurements[27].

A multicentre study conducted in India is the largest comparative study in an Asian population to date with similar observed conditions. However, EGG findings were not evaluated as the primary outcome in that study, and approximately 13% of participants did not complete the water-load test according to the protocol. Therefore, their findings are not directly comparable with the results of our study[22].

In our study, multivariate analysis showed that the association between bradygastria and T2DM persisted after adjustment for potential confounding variables. Age, BMI, and dyspepsia severity were not found to be significant predictors of gastric motility abnormalities detected by EGG.

Glycaemic control in T2DM as a protective factor against dyspepsia severity

A recent study conducted in China demonstrated that 24.62% of respondents with T2DM suffer from gastric myoelectrical dysfunction associated with the rise of fasting blood glucose, HbA1c levels, a history of diabetic peripheral neuropathy, and diabetic cardiac autonomic neuropathy[28]. Our study further explored association between glycaemic control and dyspepsia by analysing HbA1c levels among participants with T2DM and categorizing them into controlled (HbA1c < 6.5%) and uncontrolled (HbA1c ≥ 6.5%) blood glucose groups. Although no significant difference in dyspepsia scores based on the SF-LDQ was observed between the groups, interestingly, participants with controlled blood glucose levels exhibited significantly milder dyspeptic symptoms (P = 0.036). Milder dyspepsia may support better dietary adherence, which would result in better management of blood glucose. Other pathophysiological mechanisms should also be considered as our study suggested that symptoms may arise in the absence of rhythm abnormalities.

Previous studies have demonstrated an association between autonomic neuropathy and glycaemic control in relation to the postprandial-to-fasting power ratio. Increased normal dominant frequency and a reduced dominant frequency instability coefficient were also associated with improvements in glycaemic control. In contrast, EGG dominant frequency classification in our study was not associated with glycaemic control. Further longitudinal studies are needed to elaborate the temporal and causal relationships between dysrhythmia and dyspepsia severity. Our findings highlight the importance of achieving adequate glycaemic control in the management of dyspepsia in patients with T2DM, in addition to empirical treatments such as prokinetics and erythromycin, which are commonly used to improve oesophageal transit time and gastric emptying time in patients with T2DM-related dyspepsia[29-31].

Study limitations

In this study, we did not include gold standard testing (i.e. GES) as a comparator and acknowledge the limitation of such to validate EGG as a proper screening tool. During EGD, only some of the participants were tested for H. pylori using the rapid urease test. Thus, we were unable to assess H. pylori infection as a potential contributing factor to delayed gastric emptying and its association with T2DM[32-34]. We also recognize the significant baseline difference of age and BMI as another confounding factor that may have influenced our findings.

As the majority of our baseline data were obtained from the study participants’ medical records, we were unable to perform a complete assessment of several variables that were not regularly noted in medical records, including history of smoking and alcohol consumption, duration of T2DM, history of autonomic neuropathy, and intensity of dyspepsia-related pain[3-7]. Several criteria in our study may also limit generalizability to the currently expanding segment of patients with T2DM who receive GLP-1 or other medications that affect gastric motility. Further large-scale studies with more comprehensive data collection are needed to better evaluate these factors.

Furthermore, the version of 3CPM EGG system that was used in this study did not provide information on the postprandial-to-fasting power ratio and dominant frequency instability coefficient, and the normal gastric slow wave percentage required manual calculation[13]. Other versions of EGG testing software might address these variables. Nonetheless, due to this limitation, our study was designed with a focus on dominant frequency to classify primary EGG outcome. This limitation also directly impacts our analysis on the association between SF-LDQ score and EGG results. In their 2022 EGG study, Al Kafee et al[12] had found a significant association of dominant frequency (in cpm), dominant power, and instability coefficient between functional dyspepsia, diabetic gastroparesis, joint hypermobility (vs the control group); yet, analysis comparing dominant frequency category did not demonstrate any difference. Meanwhile, a meta-analysis on the associations of dyspepsia and gastric dysrhythmia provided evidence of abnormal gastric myoelectrical activity as a constant presence in dyspepsia[35].

CONCLUSION

Our study compared dyspepsia in patients with and without T2DM to evaluate how T2DM associates with dyspepsia. We demonstrated the potential role of EGG as a simple, non-invasive tool to assess gastric myoelectrical activity in patients with dyspepsia, especially those with T2DM. In this study, bradygastria was more commonly observed in T2DM, suggesting a possible gastric motility disturbance in this group of patients. Statistical analysis further indicated the association between T2DM and bradygastria in the patients with dyspepsia. Additionally, appropriate glycaemic control was found to be associated with milder dyspeptic symptoms in patients with T2DM.

We anticipate our findings will assist clinicians in the comprehensive management of dyspepsia in patients with T2DM by identifying those who will benefit from closer follow-up, optimization of glycaemic control, dietary advice, or further gastric motility evaluation. However, EGG should be interpreted as a preliminary evaluation tool and not as a substitute for standard gastric emptying tests.

ACKNOWLEDGEMENTS

We would like to thank all medical staff of the Division of Gastroenterology, Pancreatobiliary and Digestive Endoscopy, Department of Internal Medicine, Cipto Mangunkusumo National Hospital, as well as the medical staff of the Department of Internal Medicine, Mitra Keluarga Kemayoran Hospital, for their support and assistance throughout the study.