Does Grading the Severity of Gastroparesis Based on Scintigraphic Gastric Emptying Predict the Treatment Outcome of Patients with Gastroparesis?

The objectives of this study were as follows: (1) Whether gastric emptying is different between gastroparesis (GP) patients responding or not responding to standard medical therapy; (2) Identifying if mild, moderate, and severe degrees of gastroparesis based on the scintigraphic gastric emptying test (GET) can predict treatment responses for GP of diabetic (DM) and idiopathic (ID) origin. A total of 165 patients (119 F) diagnosed with GP [126 (76%) DM, 39 (24%) ID etiology] failed medical treatment and required the gastric electrical stimulation (GES) device (GES group). In addition, 112 patients (89 F) [37 (33%) DM, 75 (67%) ID] with GP who symptomatically responded to medical therapies are the comparison group (MED GP). All patients underwent a standardized scintigraphic GET consisting of low-fat (2%) isotope labeled egg beaters meal of 250 kcal. We also analyzed the GET data to find cut-off points for different degrees of GP and identified mild (11-20% retention), moderate (21-35%), and severe gastroparesis (> 35%) based on percent retention of isotope at 4 h. Overall gastric retention at 4 h was significantly greater in the GES group (45 +/- A 1.9%) than MED GP (30 +/- A 2%) (p < 0.001). The distribution severity of the GET was different in GES-treated patients than MED treated (p < 0.001). In the diabetics, 57% of GES patients retained > 35% after 4 h (severe) similar to 43% in the DM MED group. However, 50% of the ID GES patients had retention > 35% at 4 h significantly more than only 17% of ID MED GP. Significantly more ID patients who responded to medical therapy had mild gastroparesis and significantly more requiring GES had severe GET (p < 0.05). (1) GET in patients whose GP symptoms were refractory to standard medical therapy and required GES was significantly slower than in GP patients whose symptoms responded to medical therapy. (2) Stratifying GET into mild, moderate, and severe degrees of gastric retention does not predict whether a medical or surgical approach will be better to control the symptoms of diabetic GP but does correlate with treatment for the idiopathic GP subgroup.