RELIABILITY AND REPRODUCIBILITY OF BREATH HYDROGEN AND METHANE IN MALE DIABETIC SUBJECTS

We studied the variability and reliability of breath hydrogen and meth ane as well as the alterations in intestinal gas profile in response t o lactulose ingestion in 13 asymptomatic male patients with diabetes m ellitus (DM). Seventeen healthy subjects served as controls, The preva lence of methane producers was 33% in DM and 45% among control subject s (P = NS), The prevalence of nonhydrogen producers was 7.7% and 5.9%, respectively, The coefficient for interday variation of H-2 was 72.6 +/- 9.8% in DM and 49.7 +/- 9.8% in controls (P < 0.05), Similarly, th e coefficient for interday variation of CH4 was 94.3 +/- 18.8 and 69.4 +/- 16.8% respectively (P NS). The reproducibility of basal H-2 and C H4 among diabetics as assessed by r(1) (measure of reliability) was po orer among diabetics when breath analysis was performed on different d ays (P < 0.001). There was no significant difference between diabetics and controls with respect to basal or peak or area under the curve fo r H-2 and CH4 in response to lactulose. We conclude that there is poor reproducibility of fasting breath gas levels among asymptomatic male subjects with diabetes, In addition, DM is not associated with alterat ions in hydrogen- or methane-producing potential.