The gastric emptying study with oatmeal: reference range and reproducibility as a function of age and sex.

UNLABELLED This study evaluated the reference range and reproducibility of the gastric emptying study with oatmeal as a function of age and sex. METHODS Twenty-four healthy subjects, 12 men and 12 women, categorized into 3 age groups, 20-40, 40-60, and 60-80 y, were studied twice, 1 d apart, with instant oatmeal labeled with (99m)Tc-sulfur colloid. Imaging was performed in the upright position using the left anterior oblique (LAO), right posterior oblique (RPO), anterior, and posterior projections. One-minute digital images acquired every 15 min for 60 min were used to calculate a simple half-time of emptying. RESULTS A strong correlation was found among half-times of gastric emptying calculated from the anterior projection, LAO projection, anterior-posterior geometric mean, and LAO-RPO geometric mean (P < 0.01). A significant inverse correlation was found between increasing age and decreasing half-time of emptying in men and women (P < 0.05). A reference range of 10-60 min is suggested for 20- to 40-y-old patients, 10-40 min for 40- to 60-y-olds, and 10-30 min for 60- to 80-y-olds. Half-times of emptying tended to be longer for women than for men (not statistically significant). There was a large variation between the first and second studies, with a trend toward decreasing variation with increasing age in both men and women. In repeated studies, a reference range of variation of up to 30 min is suggested for 20- to 40-y-old patients, up to 20 min for 40- to 60-y-olds, and up to 15 min for 60- to 80-y-olds. CONCLUSION The reference range for half-time of gastric emptying with instant oatmeal decreases with increasing age in both men and women. Test-retest variation is relatively large and tends to decrease with increasing age in both men and women. Data from either the LAO projection or the anterior-posterior geometric mean are acceptable for calculating the half-time of gastric emptying.