The metabolic effects of pregnancy in cystic fibrosis.
OBJECTIVE
Our purpose was to determine glucose tolerance in pregnant women with cystic fibrosis (CF) and to relate glucose tolerance to insulin sensitivity, hepatic glucose production, and protein turnover.


METHODS
We studied 8 CF women during pregnancy (CFPreg). Results were compared with those from 9 pregnant controls (PregCont) and 8 nonpregnant CF women (CFCont). The following metabolic studies were conducted: oral glucose tolerance test (OGTT), hyperinsulinemic euglycemic clamp, stable isotope infusion of [1-13C]leucine and [6,6-2H2]glucose for measurement of whole body protein turnover and hepatic glucose production (HGP), respectively. Indirect calorimetry was used to measure resting energy expenditure (REE), and food intake was measured by 3-day food journals. Fat-free mass was measured by total body potassium 40K scan.


RESULTS
All but one CFPreg developed diabetes by the end of the second trimester and had significantly lower insulin secretion and more insulin resistance than PregCont. Hepatic glucose production was significantly higher and suppression by insulin was less in CF subjects, and protein breakdown was significantly higher. Insulin resistance and HGP increased during pregnancy similarly in CFPreg and PregCont groups.


CONCLUSIONS
Pregnancy in CF is associated with decreased insulin sensitivity and high HGP, in addition to inherent decreased insulin secretion. Pregnancy in CF is also associated with increased protein turnover and less response to insulin's anticatabolic effect. These changes appear to predispose the pregnant CF women to early development of diabetes and poor weight gain.
Hardin
Dana S
DS
University of Texas Southwestern Medical Center, Dallas, Texas 75093-9063, USA. dana.hardin@utsouthwestern.edu
Rice
Julie
J
Cohen
Richard C
RC
Ellis
K J
KJ
Nick
J A
JA
D000328:Adult; D003550:Cystic Fibrosis / Q000378:metabolism*; D003920:Diabetes Mellitus / Q000209:etiology; D005260:Female; D005943:Gluconeogenesis / Q000502:physiology; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000378:metabolism; D007333:Insulin Resistance; D000078790:Insulin Secretion; D008099:Liver / Q000378:metabolism; D011247:Pregnancy; D011248:Pregnancy Complications / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism
D007328:Insulin; D011506:Proteins