Showing papers by "Anny H. Xiang published in 2001"

A Randomized Controlled Trial Using Glycemic Plus Fetal Ultrasound Parameters Versus Glycemic Parameters to Determine Insulin Therapy in Gestational Diabetes With Fasting Hyperglycemia

Abstract: OBJECTIVE —To compare management based on maternal glycemic criteria with management based on relaxed glycemic criteria and fetal abdominal circumference (AC) measurements in order to select patients for insulin treatment of gestational diabetes mellitus (GDM) with fasting hyperglycemia. RESEARCH DESIGN AND METHODS —In a pilot study, 98 women with fasting plasma glucose (FPG) concentrations of 105–120 mg/dl were randomized. The standard group received insulin treatment. The experimental group received insulin if the AC, measured monthly, was ≥70th percentile and/or if any venous FPG measurement was >120 mg/dl. Power was projected to detect a 250-g difference in birth weights. RESULTS —Gestational ages, maternal glycemia, and AC percentiles were similar at randomization. After initiation of protocol, venous FPG ( P = 0.003) and capillary blood glucose levels ( P = 0.049) were significantly lower in the standard group. Birth weights (3,271 ± 458 vs. 3,369 ± 461 g), frequencies of birth weights >90th percentile (6.3 vs 8.3%), and neonatal morbidity (25 vs. 25%) did not differ significantly between the standard and experimental groups, respectively. The cesarean delivery rate was significantly lower (14.6 vs. 33.3%, P = 0.03) in the standard group; this difference was not explained by birth weights. In the experimental group, infants of women who did not receive insulin had lower birth weights than infants of mothers treated with insulin (3,180 ± 425 vs. 3,482 ± 451 g, P = 0.03). CONCLUSIONS —In women with GDM and fasting hyperglycemia, glucose plus fetal AC measurements identified pregnancies at low risk for macrosomia and resulted in the avoidance of insulin therapy in 38% of patients without increasing rates of neonatal morbidity.

Coincident Linkage of Fasting Plasma Insulin and Blood Pressure to Chromosome 7q in Hypertensive Hispanic Families

Abstract: Background Insulin resistance (IR) and hyperinsulinemia are phenotypically associated with hypertension. We have previously provided evidence that blood pressure (BP) and IR cosegregate in Hispanic families, suggesting that this association has a genetic component. In the present study, we provide further support for the hypothesis of a genetic basis for the BP-IR relationship from a genetic linkage study. Methods and Results A 10-cM genome scan was conducted in 390 Hispanic family members of 77 hypertensive probands. Detailed measurements of BP, glucose, insulin levels, and insulin sensitivity (euglycemic clamp) were performed in adult offspring of probands. Multipoint variance component linkage analysis was used. A region on chromosome 7q seemed to influence both IR and BP. The greatest evidence for linkage was found for fasting insulin (lod score=3.36 at 128 cM), followed by systolic BP (lod score=2.06 at 120 cM). Fine mapping with greater marker density in this region increased the maximum lod score f...

Evidence for joint genetic control of insulin sensitivity and systolic blood pressure in hispanic families with a hypertensive proband.

Abstract: Background —The clustering of hypertension, insulin resistance, and obesity remains unexplained. We tested for genetic and nongenetic influences on the association among these traits in Hispanic families with hypertension. Methods and Results —Blood pressure and body mass index (BMI) were measured in 331 members of 73 Hispanic families in which an index case (proband) had hypertension. Insulin sensitivity (S I ) was measured by euglycemic clamp in 287 probands and their spouses (parents’ generation) or their adult offspring. Correlation analysis examined relationships among traits within and between generations. Path analysis estimated genetic and nongenetic contributions to variability in systolic blood pressure (SBP), S I , and the correlation between them. In the offspring, there was a significant correlation between individuals for each trait, as well as significant correlations within and between individuals for all possible pairs of traits. Between generations, SBP, S I , and BMI in parents correlated with the same traits in their offspring; BMI in parents correlated with S I and SBP in offspring; and S I in parents correlated with SBP in offspring. Path analysis estimated that among offspring, genetic effects unrelated to BMI accounted for 60.8% of the variation in SBP, 36.8% of the variation in S I , and 31.5% of the correlation between SBP and S I after adjustment for age and sex. Heritable effects related to BMI accounted for an additional 14.0% of variation in SBP, 26.8% of variation in S I , and 56.3% of variation in their correlation. Conclusions —Clustering of hypertension and insulin resistance in Hispanic Americans is accounted for in part by heritable factors both associated with and independent of BMI.