Atypical Causes of Gastroparesis Prevalence, Gastric Emptying, and Clinical Features

Background: Gastroparesis is commonly attributed to idiopathic or diabetic causes. Goals: We aimed to describe atypical causes of gastroparesis and examine the clinical features and severity of delayed gastric emptying compared with idiopathic and diabetic causes. Study: Between 2018 and 2021, gastroparesis patients being evaluated at our tertiary care center completed a 4-hour gastric emptying scintigraphy and questionnaires assessing for gastrointestinal disorders, including patient assessment of upper gastrointestinal symptoms. Patients were divided into groups relating to gastroparesis cause: diabetic, postsurgical (PSGp), connective tissue (CTGp), neurological and idiopathic. Results: Two hundred fifty-six patients with delayed emptying on gastric emptying scintigraphy completed the questionnaires. Gastroparesis causes included 149 (58.2%) idiopathic, 60 (23.4%) diabetic, 29 (11.3%) postsurgical, 13 (5.1%) connective tissue, and 5 (2.0%) neurological. In each group, most patients were female and White. Gastric retention at 4 hours was significantly greater in patients with diabetic (39.3 +/- 25.7% P<0.001), postsurgical (41.3 +/- 24.0% P=0.002), and connective tissue gastroparesis (37.8 +/- 20.0% P=0.049) compared with patients with idiopathic gastroparesis (25.5 +/- 17.6%). In PSGp, diabetic and idiopathic causes, the main symptoms were early satiety and postprandial fullness, whereas in CTGp, bloating and abdominal distension were the predominant symptoms. Vomiting severity was significantly greater in patients with diabetes compared with idiopathic gastroparesis (2.9 +/- 1.9 vs. 2.1 +/- 1.8 P=0.006). Conclusions: Atypical causes contributed to gastroparesis in 47 of 256 (18.4%) patients with delayed gastric emptying. Gastric emptying was significantly more delayed in PSGp and CTGp patients. PSGp patients mainly experienced stomach fullness and early satiety, whereas CTGp patients had predominantly bloating and distension.