Comparison of Body Mass Index (BMI) of Symptomatic Patients With and Without Gastroparesis: A Retrospective Study

Abstract

Introduction: Gastroparesis is a condition characterized by delayed gastric emptying. Symptoms of gastroparesis include early satiety, post-prandial fullness, bloating, nausea, vomiting and abdominal discomfort which may cause malnourishment and weight loss. Diabetes mellitus and hypothyroidism are common etiologies of gastroparesis which are associated with metabolic derangements and obesity. We conducted a retrospective study to compare the BMI of symptomatic patients with and without gastroparesis. Methods: A retrospective study at a single tertiary-care center was performed after IRB approval. All adult patients that underwent gastric emptying scintigraphy (GES) at our hospital from January 2013 through August 2014 were included. Patient charts were reviewed for the following data: Age, gender, BMI, causes of gastroparesis and GES results. The weight status of the patients was categorized according to the BMI range (underweight BMI < 18.5, normal weight: BMI 18.5-24.9, overweight: BMI 25.0-29.9, obese: BMI ≥30 kg/m2). Statistical analysis was performed using descriptive statistics, two-tailed unpaired t-test for continuous data, and Fisher's exact test for categorical data with statistical significance defined as p< 0.05. Results: A total of 596 patients who underwent GES were identified consisting of 152 males and 444 females with mean age 47.8 ± 16.3 years. Out of these, 292 patients were in the non-gastroparesis (non-GP) group who had normal GES results. There were 304 patients in the gastroparesis (GP) group with delayed gastric emptying documented by abnormal GES. The mean BMI of the non-GP group was 29.57 ± 8.61 kg/m2 versus 31.09 ± 9.32 kg/m2 in the GP group (p=0.04). In the non-GP group (n=292), there were 10 underweight, 66 normal weight, 70 overweight and 146 obese patients. In the GP group (n=304), there were 23 underweight, 63 normal weight, 82 overweight and 136 obese patients. Gastroparesis was identified more in those patients with BMI ≤18.5 kg/m2 than those >18.5 (p=0.03). No differences were noted for gastroparesis in those patients overweight with BMI ≥30 kg/m2 (p=0.22) and morbidly obese with BMI ≥40 kg/m2 (p=0.57) as compared to other groups. Conclusion: Symptomatic patients with gastroparesis are significantly more likely to be underweight with BMI < 18.5 kg/m2. This may be due to malnourishment and weight loss due to gastroparesis symptoms, and it emphasizes the importance of dietary counseling in these patients.