Chronic Vestibular Dysfunction: An Unappreciated Cause of Chronic Nausea and Vomiting: ACG /AstraZeneca Fellow Award

Abstract

Purpose: Patients with chronic nausea and/or vomiting who are not found to have structural lesions of the stomach are frequently diagnosed as having gastroparesis. This impression may be strengthened by an abnormal gastric emptying scan. When standard treatments fail, these patients may be referred to a center for advanced therapy. We reviewed the records of patients referred to our center for chronic nausea and vomiting over a three year period to learn about their subsequent diagnosis and management. Methods: Consecutive outpatients referred for chronic nausea and vomiting from January 2008—December 2010 were identified from billing records. Medical records were reviewed to characterize evaluation and treatment before referral, subsequent investigation, and response to treatment. Results: Of 248 patients referred for chronic nausea and vomiting during this interval, 156 (62.9%) were referred with a diagnosis of gastroparesis. 95 of these patients had abnormal non-standardized gastric emptying tests [duration <4 hours, atypical test meal, concurrent symptoms, confounding medications]; repeat testing using the international standard protocol was done in 36 patients and was normal in 27 (75.0%). Only 28 patients from the initial cohort (11.3%) had a final diagnosis of gastroparesis. Other diagnoses included cyclical vomiting syndrome (8.8%), rumination syndrome (1.2%), postsurgical syndromes (2.0%), medication-induced vomiting (1.2%), GERD (2.4%), and unspecified or other (47.3%). The most common specific diagnosis in this cohort was chronic vestibular dysfunction (CVD, 64 patients, 25.8%). This diagnosis was made on the basis of an abnormal modified Fukuda stepping test (>90° rotation within 60 seconds while marching in place with eyes closed and ears occluded), presence of nystagmus, or abnormal Romberg test. 43 (67.2%) of these patients had been referred for “gastroparesis.” Most had had an abnormal nonstandard gastric emptying scan; when a standardized test was repeated, it was normal in 8 of 9. As compared to patients ultimately diagnosed with other conditions, CVD patients more often presented with nausea alone. Diabetes was present in similar proportions in CVD and non-CVD patients (20% vs 27.2%, p=0.27). Vertigo was reported by only 6 (9.4%). 57 of 64 CVD patients were given trials of anti-vertiginous medications; of the 39 followed for a median of 5 months, improvement occurred in two-thirds. Conclusion: Diagnosis of gastroparesis should not be based on a non-standardized gastric emptying test. Gastroparesis was an unlikely diagnosis in our cohort. Chronic vestibular dysfunction was a much more likely diagnosis. Treatment for this condition may mitigate nausea and vomiting.