Reproductive history, glucose tolerance, and NIDDM in Hispanic and non-Hispanic white women. The San Luis Valley Diabetes Study.
OBJECTIVE
To ascertain whether childbearing would decrease oral glucose-stimulated insulin and C-peptide levels and increase the risk of NIDDM and impaired glucose tolerance in a population of Hispanic and non-Hispanic white women residing in the San Luis Valley of Colorado. Several investigators have related childbearing to subsequent abnormal glucose tolerance.


METHODS
In a population-based case-control epidemiological study, diabetic patients 20-74 yr of age (n = 196) and randomly sampled control women subjects (n = 735) underwent a glucose tolerance test, a physical examination, and an in-person standardized interview. The relations between the live-birth number and fasting and oral glucose stimulated glucose, insulin and C-peptide concentrations, and NIDDM and impaired glucose tolerance were estimated using linear or logistic regression to adjust for extraneous variables.


RESULTS
In women selected as control subjects, the live-birth number was related to a significant decrease in the sum of 1- and 2-h C-peptide concentrations (coefficient = -0.077, P < 0.001) and the logarithm of the sum of 1- and 2-h insulin concentrations (coefficient = -0.014, P = 0.02). After adjustment for subscapular skin-fold thickness, the relative odds of NIDDM for the live-birth number, which was small and of borderline significance, diminished (odds ratio = 1.04 for one birth, P = 0.18). Findings were similar for impaired glucose tolerance.


CONCLUSIONS
Childbearing was related to lower C-peptide and insulin levels in Hispanic and non-Hispanic women of the San Luis Valley. It had little apparent effect on later risk of NIDDM or impaired glucose tolerance.
Alderman
B W
BW
Department of Epidemiology, University of Washington School of Public Health, Seattle 98195.
Marshall
J A
JA
Boyko
E J
EJ
Markham
K A
KA
Baxter
J
J
Hamman
R F
RF
D000328:Adult; D000367:Age Factors; D000368:Aged; D001786:Blood Glucose / Q000378:metabolism*; D002096:C-Peptide / Q000097:blood; D003120:Colorado / Q000453:epidemiology; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology*; D005006:Ethnicity; D005260:Female; D018149:Glucose Intolerance / Q000453:epidemiology*; D005951:Glucose Tolerance Test; D006630:Hispanic or Latino; D006801:Humans; D007328:Insulin / Q000097:blood*; D008487:Medical History Taking; D008875:Middle Aged; D010298:Parity; D011247:Pregnancy; D012044:Regression Analysis; D012307:Risk Factors; D044465:White People
D001786:Blood Glucose; D002096:C-Peptide; D007328:Insulin