Leptin in Cord Blood Associates with Asthma Risk at Age 3 in the Offspring of Women with Gestational Obesity.

RATIONALE Maternal obesity is associated with asthma in the offspring. Whether maternal leptin is associated with risk of asthma in offspring is unclear. OBJECTIVE To assess whether leptin levels in maternal obesity predict preschool asthma. METHODS In this birth cohort study, we divided pregnant women into three weight categories during the first obstetric visit: normal ("NL"), overweight ("OW") and obese ("OB"). RESULTS We followed the offspring recording atopy, wheezing, and other respiratory illnesses through 30 months of age. Cord blood and peripheral blood at 30 months of age were taken to measure cytokines, adipokines, metabolic biomarkers, and specific IgE. Adjusted regression models were used to evaluate the association between maternal obesity and offspring asthma risk, defined by a positive Asthma Predictive Index (API). 339 mothers were recruited; 140 offspring were born from NL, 80 from OW, and 119 from OB mothers. OB women were older, less educated, had higher parity, and higher C-section frequency. Offspring from OB women had higher birthweight, head circumference, and placental weight compared to other groups. The proportion of API+ at 30 months of age was 12.2% in the NL, 14.7% in the OW, and 16.8% in the OB group (p=0.18). Offspring from OB women had higher leptin, leptin/adiponectin ratio, IL-10 and insulin than the OW group; and higher leptin than the NL group. In the adjusted analysis, offspring from OB mothers with high cord-blood leptin had increased risk of asthma (aOR=1.30 [95%CI=1.1-1.55], p=0.003). CONCLUSION Offspring from obese mothers with high cord blood leptin have 30% higher asthma risk at age 3. Clinical trial is registered with ClinicalTrials.gov (NCT02903134).