14C triolein breath test: an assessment in the elderly.

14C triolein breath tests are highly sensitive in detecting fat malabsorption in adults, but experience in the elderly is sparse. We have evaluated 48 'normal' subjects over the age of 65 years and compared the results with those of 46 normal subjects under 65 from a previous study. Results were calculated as eight hour cumulative values and expressed as percentages of the administered dose. Reference ranges have been calculated separately for the following age groups: 65 years or less (201 to 460), 66 to 75 (182 to 405) and over 75 (141 to 336). A clear age related decline in eight hour cumulative values was noted. The values fell by 23% between the ages of 17 and 65 years and by 25% between the ages of 65 and 87 years. Pancreatic insufficiency or bacterial colonisation of the small bowel is unlikely, but delayed intestinal absorption or the effects of slower metabolic rate cannot be excluded. This test is simple and practicable in the elderly and the study emphasises the importance of age in the interpretation of results.