Clinical insights into diabetic gastroparesis: gastric scintigraphy-based diagnosis and treatment outcomes

Background Long-standing diabetes mellitus (DM) can lead to macrovascular and microvascular complications including autonomic neuropathy, which disrupts gut motility. Gastroparesis (GP) is defined as delayed gastric emptying of solids (with or without liquids) in the absence of any mechanical obstruction. The gold standard test for the diagnosis of gastroparesis is gastric scintigraphy (GS) using a solid meal. Gastroparesis poses diagnostic and therapeutic challenges, and can significantly impact patients with DM. The purpose of this study is to evaluate the utility of solid gastric scintigraphy in diagnosing gastroparesis, and to assess the outcomes of medical treatment and gastric per-oral endoscopic myotomy (G-POEM) in patients with DM. Patients and Methods From June 2022 to June 2024, all patients visiting the diabetes clinic in Cairo University Hospital for any reason were screened for symptoms of gastroparesis using the gastroparesis cardinal symptom index (GCSI). Symptomatic patients underwent solid gastric scintigraphy. Those diagnosed with GP were treated for three months and refractory cases were offered G-POEM. Results Thirty-two patients with moderate-to-severe symptoms of gastroparesis were the population of this study. Of these, 62.5% had delayed gastric emptying on solid gastric scintigraphy. A GCSI > 23 independently predicted delayed gastric emptying on solid gastric scintigraphy (OR 1.153, 95% CI (1.009 – 1.317), p = 0.036) . 55% of GP patients achieved improvement in symptoms after three months of optimized medical therapy, and two out of four cases had sustained improvement for one year after G-POEM. The responders to medical treatment were significantly older in age, had lower GCSI and greater reduction in hemoglobin A1c (HbA1c) compared to those in refractory group (p = 0.046, 0.012, 0.012 respectively) . Conclusion This study highlighted the role of the GCSI in assessing and monitoring gastroparesis, particularly in resource-limited settings. Diabetic GP differs in clinical presentation and management from other types of GP. Optimizing glycemic control may contribute to symptoms improvement. Patients with higher GCSI can be refractory to medical treatment and may benefit from early referral for alternative interventions such as G-POEM, potentially avoiding prolonged ineffective treatment.