Relative Weight Gain Through Age 4 Years Is Associated with Increased Adiposity, and Higher Blood Pressure and Insulinemia at 4-5 Years of Age in Mexican Children

Background: Rapid early weight gain has been associated with increased risk of obesity and cardiometabolic alterations, but evidence in low and middle-income countries is inconclusive. Objective: We evaluated the relation between relative weight gain from 1 to 48 mo with adiposity and cardiometabolic risk factors at 4-5 y of age, and determined if adiposity is a mediator for cardiometabolic alterations. Methods: We studied 428 Mexican children with anthropometric and blood pressure (BP) information from birth to 5 y of age from POSGRAD (Prenatal Omega-3 fatty acid Supplementation and child GRowth And Development), of whom 334 provided measures of adiposity and cardiometabolic risk markers at 4 y. We estimated relative weight gain by means of conditional weight-for-height z scores for the age intervals 1-6, 6-12, 12-24, and 24-48 mo. Associations between relative weight gain and adiposity and cardiometabolic risk markers (lipid profile, triglycerides, insulin, glucose, and BP) were analyzed by multivariate multiple linear models and path analysis. Results: A 1-unit increase in conditional weight-for-height z score within each age interval was positively associated with adiposity at 5 y, with coefficients of 0.43-0.89 for body mass index (BMI) z score, 1.08-3.65 mm for sum of skinfolds, and 1.21-3.87 cm for abdominal circumference (all P < 0.01). Positive associations were documented from ages 6 to 48 mo with systolic BP (coefficient ranges: 1.19-1.78 mm Hg; all P < 0.05) and from ages 12 to 48 mo with diastolic BP (1.28-0.94 mm Hg; P < 0.05) at 5 y. Conditional weight-for-height z scores at 12-24 and 24-48 mo of age were more strongly associated with adiposity and BP relative to younger ages. A unit increase in conditional weight-for-height z scores from 12 to 24 mo was associated with 14% higher insulin levels (P < 0.05) at 4 y. Path analyses documented that the associations of conditional weight gain with BP were mediated by BMI and sum of skinfolds. Conclusion: Relative weight gain at most periods during the first 4 y of life was associated with greater adiposity and higher systolic and diastolic BP at 5 y. These associations with BP were mediated by adiposity. Relative weight gain from 12 to 24 mo was associated with increased serum insulin concentrations at 4 y, but there were no associations with lipid profiles or glucose concentration.