Birth weight correlates differently with cardiovascular risk factors in youth

Childhood obesity has become prevalent, resulting in a greater risk of hypertension, diabetes, and dyslipidemia. However, the relationship between these comorbid conditions and birth weight remains uncertain. We conducted this study to evaluate the relationship between birth weight and cardiovascular risk factors in children and adolescents.

In a nationwide survey conducted between 1992 and 2000, all schoolchildren 6 to 18 years old with glucosuria, proteinuria, or microscopic hematuria in repeated urine samples were included and received a physical examination and blood test. Those with gestational age <37 weeks were excluded. We enrolled 81,538 children (51,111 girls and 30,427 boys) and obtained their birth weights from the Taiwan Birth Registry. Obesity and hypertension were defined by age- and sex-specific cut-offs. Diabetes was diagnosed if the fasting glucose was >7 mM.

The risk of obesity was higher for those with birth weights > or =4000 grams [odds ratio (OR), 1.65] and 3543 to 3999 grams (OR, 1.28) and lower for those with birth weights 2601 to 2999 grams (OR, 0.90), using 3000 to 3542 grams as the reference group. An increased risk of diabetes was associated with both higher and lower birth weights, indicating a U-shaped relationship (OR, <2600 grams, 1.607; 2601 to 2999 grams, 1.119; 3543 to 3999 grams, 1.112; > or =4000 grams, 1.661). In the 10- to 12-year-old age group, the risk of hypertension was higher in those with birth weights <2600 grams (OR, 1.20).

Low birth weight was associated with childhood diabetes. High birth weight was correlated with childhood obesity and diabetes. Our data indicate different relationships between birth weight and the development of obesity, hypertension, and diabetes in childhood.