Peer-reviewed article
SUN-077 Do Low Sex Hormone Binding Globulin Levels in Newborns Predict Weight Gain in Infancy and Early Childhood?
Aydin B, Yasa B, Moore J, Yasa C, Poyrazoglu S et al. ·
Summary
Written by AI, not yet AICS's view · claude-haiku-4-5-20251001This medical research study examined whether low levels of sex hormone binding globulin (SHBG) in newborn blood could predict childhood obesity. Researchers measured SHBG and insulin levels in cord blood and day 2 blood samples from 94 newborns, then followed 47 of them to age 2 years with anthropometric measurements. While the heaviest newborns had lower SHBG levels, low SHBG at birth did not predict being overweight at age 2, though day 2 SHBG levels did correlate with weight at 6 and 24 months after adjusting for other factors.
Key points
- SHBG levels were significantly higher on day 2 compared to cord blood
- Babies with highest ponderal index values had lower day 2 SHBG and higher cord blood insulin levels
- At age 2 years, 32% of followed children were overweight or obese
- Screen viewing and sweet snack consumption were associated with higher weight at age 2
- Low SHBG at birth did not predict overweight status at age 2 years
Limitations
This is a biomarker prediction study focused on a specific physiological marker rather than an intervention to improve child well-being. The follow-up sample was small (n=47 of 94 original cohort) and attrition reasons are not explained, which could bias results.
Abstract
Abstract Background: SHBG levels are low in obesity, and low SHBG levels are a biomarker for the development of T2DM and the metabolic syndrome. We sought to determine whether low SHBG in newborns will predict childhood obesity. Methods: We studied 94 healthy, singleton, full-term newborns, and measured their length, weight (BW), waist circumference, and skinfold thicknesses. We collected cord blood as well as day 2 venous blood samples for the measurement of SHBG and insulin (ALPCO, Salem NH). Maternal age, pre-pregnancy weight, pregnancy weight gain, and glucose screening test results were obtained from obstetrical records. Mothers with chronic diseases were excluded from the study. When babies were 2 years old, we administered a questionnaire to collect information about their eating, sleeping, screen viewing habits, and anthropometric measurements at ages 6, 12, and 24 months (n=47). Overweight was defined as a BMI SDS of ≥1 and <2.0, and obesity as ≥2 SDS. We used the Shapiro-Wilk test to determine if variables were normally distributed. Data were analyzed using the Mann Whitney U and Wilcoxon signed-rank tests, and by Pearson or Spearman correlation analyses. We report non-normally distributed variables as medians and interquartile ranges (IQR). Because of skewed distributions, log 10 transformed values for SHBG were used in the regression analyses. Results: SHBG levels on day 2 were significantly higher than in cord blood [22.0(28.7-16.9) vs. 19.0(24.6-14.5) nmol/L, p<0.001], whereas insulin levels were higher in cord blood than in day 2 samples [3.2(5.3-2.0) vs. 1.5(2.2-0.8) µIU/mL, p<0.001]. SHBG and insulin levels were similar in male (n=44) and female (n=50) babies at all time points. Babies with Ponderal index values in the highest quartile had lower day 2 SHBG [18.2(22.1-16.7) vs. 24.3(30.3-18.2) nmol/L, p=0.02] and higher cord blood insulin levels [5.0(7.4-2.6) vs. 2.9(4.8-1.5) µIU/mL, p=0.04] than the remainder of the cohort. At age 2 years, 32% (15/47) of babies were overweight or obese, 60% (28/47) were breastfeeding, 58% (27/47) were watching TV or iPads, and 55% (26/47) were eating sweet snacks. Toddlers watching TV or iPads (p=0.008), or eating sweet snacks (p=0.04) were heavier than their peers. Neither cord blood nor day 2 SHBG or insulin levels correlated significantly with any of the anthropometric measurements in the newborns. On the other hand, day 2 SHBG levels correlated positively with weight at 6 (r=0.311, p=0.04) and 24 months (r=0.353, p=0.02) of age. These associations remained significant after adjusting for gender, BW, gestational age, breastfeeding status and fruit juice intake at 6 months (R2=0.28, p=0.048) and for gender, BW, gestational age, breastfeeding status, sweet snack intake and screen viewing habits at 24 months (R2=0.33, p=0.046). Conclusion: Although the heaviest babies had lower SHBG levels at birth, low SHBG did not predict overweight at age 2 years.