A cross-sectional study describing peripheral neuropathy in patients with symptoms of gastroparesis: associations with etiology, gastrointestinal symptoms, and gastric emptying

BACKGROUND: Peripheral neuropathy (PN) is present in diabetic gastroparesis but is not described in idiopathic gastroparesis. AIMS: (1) Determine prevalence of PN in idiopathic gastroparesis; (2) assess if patients with symptoms of gastroparesis and PN differ in gastric emptying and symptoms, both gastrointestinal and psychosocial, from patients without PN (nPN); (3) compare this relationship to that in other etiological groups. METHODS: 250 patients with symptoms of gastroparesis underwent gastric emptying scintigraphy and answered questionnaires including severity of gastroparesis symptoms using the Gastroparesis Cardinal Symptom Index (GCSI) and presence of peripheral neuropathy using the Neuropathy Total Symptom Score-6 (NTSS-6). RESULTS: PN, defined by NTSS-6 > 6, was present in 70/250 (28%) patients: 22/148 (15%) idiopathic, 33/61 (54%) diabetic, and 11/32 (34%) postsurgical (p < 0.01). Among 148 patients with symptoms of idiopathic gastroparesis, defined as non-diabetic, non-postsurgical, and not caused by a known disorder such as Parkinson’s or connective tissue disease, symptoms of gastroparesis were more severe in PN than nPN: bloating (4.05 ± 1.17 vs. 2.99 ± 1.61, p < 0.01), abdominal distension (3.86 ± 1.49 vs. 2.45 ± 1.68, p < 0.01), and upper abdominal pain (3.64 ± 1.22 vs. 2.71 ± 1.78, p = 0.03). Ninety-nine idiopathic patients underwent gastric emptying scintigraphy: 7/43 (16%) patients with delayed gastric emptying and 9/56 (16%) patients with normal gastric emptying had PN. Among patients with idiopathic gastroparesis, abdominal distension (4.43 ± 0.53 vs. 2.89 ± 1.68, p = 0.01) was more severe in PN than nPN. The association of PN and worse gastrointestinal symptoms was not as apparent in patients with symptoms of diabetic or postsurgical gastroparesis. CONCLUSIONS: PN was present in 70/250 (28%) of patients with symptoms of gastroparesis and was present to a lesser extent in idiopathic than diabetic gastroparesis. The presence of PN in IG was associated with more severe gastroparetic symptoms than in nPN. Screening for PN may help identify a gastroparesis cohort with peripheral neuropathy who are more symptomatic.