Diabetes, Vol 31, Issue 5 385-387, Copyright © 1982 by American Diabetes Association
Ten-year prognosis of impaired glucose tolerance in siblings of patients with insulin-dependent diabetes
AL Rosenbloom, SS Hunt, EK Rosenbloom and NK Maclaren
We traced 105 of 140 siblings of children with insulin-dependent diabetes
(IDD) who had had oral glucose tolerance tests (OGTT) 10-12 yr earlier.
Siblings with abnormal tests by screening criteria (8.3 mmol/L at 1 h, 7.2
at 2 h, N = 44) included all 6 who subsequently developed IDD after 3 mo to
7 yr (5.7% of entire group, 13.6% of abnormal screenees). The National
Diabetes Data Group criterion for children (7.8 mmol/L at 2 h) identified
19 siblings, including 5 of the 6 who later developed IDD (26% of
abnormals). Subsequent full 4-h OGTT, including analysis of insulin
responses, did not improve predictability for subsequent IDD. Thus,
siblings of IDD were identified at high risk (14-26%) or at low risk (0-1%)
for subsequent IDD by a simple 2-h OGTT. The prolonged latency in the
development of IDD indicates that, among siblings of IDD, this disorder may
be already chronic for years by the time of clinical onset.