Relationship of Early Pregnancy Waist-to-Hip Ratio versus Body Mass Index with Gestational Diabetes Mellitus and Insulin Resistance.
OBJECTIVE
To determine the risk of gestational diabetes mellitus (GDM) and insulin resistance (IR) in obesity defined by body mass index (BMI), waist-to-hip ratio (WHR), or both combined.


METHODS
Secondary analysis of a randomized multicenter trial of antioxidant supplementation versus placebo in nulliparous low-risk women to prevent pregnancy associated hypertension. Women between 9 and 16 weeks with data for WHR and BMI were analyzed for GDM (n = 2,300). Those with fasting glucose and insulin between 22 and 26 weeks (n = 717) were analyzed for IR by homeostatic model assessment of IR (normal, ≤ 75th percentile). WHR and BMI were categorized as normal (WHR, < 0.80; BMI, < 25 kg/m(2)); overweight (WHR, 0.8-0.84; BMI, 25-29.9 kg/m(2)); and obese (WHR, ≥ 0.85; BMI ≥ 30 kg/m(2)). Receiver operating characteristic curves and logistic regression models were used.


RESULTS
Compared with normal, the risks of GDM or IR were higher in obese by BMI or WHR. The subgroup with obesity by WHR but not by BMI had no increased risk of GDM. BMI was a better predictor of IR (area under the curve [AUC]: 0.71 [BMI], 0.65 [WHR], p = 0.03) but similar to WHR for GDM (AUC: 0.68 [BMI], 0.63 [WHR], p = 0.18).


CONCLUSIONS
Increased WHR and BMI in early pregnancy are associated with IR and GDM. BMI is a better predictor of IR compared with WHR. Adding WHR to BMI does not improve its ability to detect GDM or IR.
Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, Texas.
Sanmaan K
SK
Basraon
Biostatistics Center, George Washington University, Washington, District of Columbia.
Lisa
L
Mele
University of Cincinnati, Cincinnati, Ohio.
Leslie
L
Myatt
University of Pittsburgh, Pittsburgh, Pennsylvania.
James M
JM
Roberts
University of Alabama at Birmingham, Birmingham, Alabama.
John C
JC
Hauth
University of Texas Southwestern Medical Center, Dallas, Texas.
Kenneth J
KJ
Leveno
University of Utah Health Sciences Center, Salt Lake City, Utah.
Michael W
MW
Varner
Columbia University, New York, New York.
Ronald J
RJ
Wapner
University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
John M
JM
Thorp
Northwestern University, Chicago, Illinois.
Alan M
AM
Peaceman
University of Texas Health Science Center at Houston-Children's Memorial Hermann Hospital, Houston, Texas.
Susan M
SM
Ramin
Drexel University, Philadelphia, Pennsylvania.
Anthony
A
Sciscione
Oregon Health & Science University, Portland, Oregon.
Jorge E
JE
Tolosa
Wayne State University, Detroit, Michigan.
Yoram
Y
Sorokin
D000328:Adult; D019540:Area Under Curve; D001724:Birth Weight; D015992:Body Mass Index; D016640:Diabetes, Gestational / Q000453:epidemiology*; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D007333:Insulin Resistance; D016015:Logistic Models; D015999:Multivariate Analysis; D009765:Obesity / Q000150:complications*; D011247:Pregnancy; D012372:ROC Curve; D012307:Risk Factors; D014481:United States; D049629:Waist-Hip Ratio; D055815:Young Adult