Abstract
To clarify insulin treatment in the elderly, we compared twice-daily insulin injection regimens in type 2 diabetic patients in four age groups. Daily insulin doses in groups were not changed, but older patients tended to consume more insulin in the morning and less insulin in the evening than middle-aged diabetics, i.e., the ratio of insulin doses in the morning to daily insulin doses increased but decreased in the evening among the elderly. We found no relationship of these ratios to renal function. An age-related decrease in urinary CPR excretion was observed, but plasma CPR levels before and after breakfast did not differ among groups. Daily plasma insulin profiles in patients with twice-daily injections of premixed insulin consisting of 30% aspart and 70% protaminated insulin aspart were higher in the elderly than in the middle-aged. Delayed insulin metabolism thus may affect insulin injection regimens in elderly patients. These results show that aging is an important factor in determining insulin regimens.
