Diabetes Care, Vol 16, Issue 9 1254-1261, Copyright © 1993 by American Diabetes Association
Administration of sulfonylureas can increase glucose-induced insulin secretion for decades in patients with maturity-onset diabetes of the young
SS Fajans and MB Brown
Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor.
OBJECTIVE--To ascertain whether the effect of sulfonylureas on
glucose-mediated insulin release persists for years to decades in patients
with maturity-onset diabetes of the young. RESEARCH DESIGN AND METHODS--The
effect of sulfonylurea treatment on glucose-induced insulin secretion was
ascertained prospectively for up to 33 yr in 12 diabetic patients of the
maturity-onset diabetes of the young RW pedigree, who are genetically
homogeneous because they share DNA markers on chromosome 20q. In 7 of these
patients, paired glucose tolerance tests, given while the patients were on
and off sulfonylureas, were performed after 7-31 yr.
RESULTS--Glucose-induced insulin secretion showed an average increase of
68% in diabetic patients who remained responsive to chlorpropamide after
having been on and off the drug for decades. In most patients, however,
glucose-induced insulin secretion declines over time (1-4%/yr). Some
patients become unresponsive to sulfonylureas after 3-25 yr and then have
very small or no increases in glucose-induced insulin secretion and require
treatment with insulin to normalize fasting hyperglycemia.
CONCLUSIONS--Increase in glucose-induced insulin secretion remains the most
important mechanism of the action of sulfonylureas during long-term
administration.