The Gastroparesis Registry 3 (GpR3) was an observational study of adult patients with symptoms of gastroparesis (Gp) and functional dyspepsia (FD) with either delayed or normal gastric emptying. To better understand these disorders, this registry captured demographic, clinical, physiological, and patient outcome data to characterize the patients and their clinical course. The study population was 406 adults aged 18 or over, located in the United States, with symptoms of gastroparesis and/or functional dyspepsia. Participants were recruited from the six clinical sites of the GpCRC located throughout the United States. The study enrolled and followed participants from January 2019 through April 2024.

• To create a new registry of patients with symptoms of gastroparesis, both patients with delayed gastric emptying and patients with similar symptoms but normal gastric emptying, for the enhanced study of symptoms, gastric motility abnormalities, patient characteristics, and degree of morbidity.
• To follow a well-characterized cohort to further define the natural history and clinical course of patients with symptoms of gastroparesis – both symptoms and gastric emptying over time. Treatments given for their clinical care and clinical responses to treatments will be recorded.
• To provide a reliable source for recruitment of well-characterized patients with gastroparesis for other studies including therapeutic clinical trials, pathophysiological, molecular, histopathologic, or other ancillary studies. These subsequent clinical trials or ancillary studies will be conducted under separate study protocols with separate consent processes.

• Assess several areas of gastric motility in patients with symptoms of gastroparesis (fundic accommodation, antral contractility, global gastric emptying).
• Determine the change in gastric motility over time, in patients with gastroparesis and in patients with symptoms of gastroparesis but normal gastric emptying.
• Evaluate the clinical symptomatic course (outcome) of patients followed in the registry.
• Use the registry to better capture clinical treatment responses to specific treatments while patients are in the registry.
• Characterize abdominal pain in patients with gastroparesis and gastroparesis-like syndrome by:
• Describing the abdominal pain seen in patients with gastroparesis
• Determining if the pain has neuropathic or nociceptive qualities
• Determining attributes of patients with abdominal pain
• Assessing patients in the presence of sensory gastric dysfunction
• Objective mapping of the abdominal pain and determining central and/or peripheral attributes of the abdominal pain

Measures the patient’s interactions with the healthcare system (e.g., hospitalizations and emergency department visits)

Measure the frequency and clinical Implications of chronic abdominal wall pain assessed by the Carnett’s Sign Test in Patients with Symptoms of Gastroparesis

Pain Characterization of Patients with Gastroparesis and Correlation with Symptoms

• Symptoms of gastroparesis of at least 12 weeks’ duration with varying degrees of nausea, vomiting, early satiety, postprandial fullness
• An etiology of either diabetic, idiopathic, or post-fundoplication (Nissen, Dor, or Toupet) gastroparesis or gastroparesis-like disorder (symptoms of gastroparesis but normal gastric emptying)
• Gastric emptying scintigraphy of solids using the 4-hour Egg Beaters® protocol (or equivalent generic liquid egg white meal) within the last 6 months with either:
• Abnormal gastric emptying rate defined as an abnormal 2 hour (>60% retention) and/or 4 hour (>10% retention) result based on a 4 hour scintigraphic gastric emptying study. (This group will comprise ~75% of patients in the registry.)
• Patients with a normal gastric emptying rate, but who have symptoms of gastroparesis. (This group will comprise ~25% of patients in the registry.)
• Negative upper endoscopy or upper radiographic GI series within 2 years of registration
• Age at least 18 years at initial screening visit

• Inability to comply with or complete the gastric emptying test by scintigraphy (including allergy to eggs)
• Use of narcotic analgesics greater than three days per week
• Presence of other conditions that could explain the patient’s symptoms:
• Pyloric or intestinal obstruction: by EGD, UGI, or Abdominal CT
• Active inflammatory bowel disease
• Known eosinophilic gastroenteritis or eosinophilic esophagitis
• Primary neurological conditions that can cause nausea and vomiting such as increased intracranial pressure, space occupying or inflammatory/infectious lesions
• Acute renal failure
• Chronic renal failure (serum creatinine >3 mg/dL) and/or on hemodialysis or peritoneal dialysis
• Acute liver failure
• Advanced liver disease (Child's B or C; a Child-Pugh-Turcotte (CPT) score of ≥7)
• Prior gastric surgery including total or subtotal (near complete) gastric resection, esophagectomy, gastrojejunostomy, gastric bypass, gastric sleeve, pyloroplasty, pyloromyotomy. Note: patients with prior Nissen, Dor, or Toupet fundoplication will be eligible for enrollment.
• Any other condition, which in the opinion of the investigator, could explain the symptoms or interfere with study requirements
• Inability to obtain informed consent

The study enrolled 406 participants. GpR3 participants are invited to enroll in the GpCRC Gastroparesis Registry 4 (GpR4) study. Analyses are ongoing.