CHANGES IN DIABETIC URINARY TRANSFERRIN EXCRETION AFTER MODERATE EXERCISE

Microalbuminuria following submaximal exercise testing has been propos ed for detecting renal abnormalities in diabetic patients. We compared urinary transferrin and albumin excretion between eight adults with i nsulin dependent diabetes mellitus and eight nondiabetic controls with out microalbuminuria before and after a standardized exercise challeng e of only moderate intensity for 20 min. Both groups were similar for age, sex, and METs expended during treadmill walking. Urinary excretio n ratios of transferrin (UTER) and albumin (UAER) did not significantl y increase for nondiabetic subjects. After exercise, UTER increased on average 207% in diabetic subjects (P = 0.009) and UAER increased 209% (P = 0.046). The percent increase in UTER appears to be a function of workload intensity, while the percent increase in UAER appears less d ependent on the duration of exercise. A standardized treadmill challen ge of moderate intensity easily differentiated changes in urinary tran sferrin excretion ratios between diabetic and nondiabetic subjects. Me asuring transferrin excretion may be a more sensitive parameter than a lbumin in studies using urinary protein excretion as a response to a p rovocative exercise challenge.