Birth Order May Affect Metabolic, Cardiac Risk

Unrecognized MI Prevalent in Older Adults, Ups Mortality
Unrecognized MI Prevalent in Older Adults, Ups Mortality
Birth order may influence metabolic and cardiovascular disease risk factors, including insulin sensitivity and daytime blood pressure.

(HealthDay News) – Birth order may influence metabolic and cardiovascular disease risk factors, including insulin sensitivity and daytime blood pressure, according to a study published online Jan. 30 in the Journal of Clinical Endocrinology & Metabolism.

Ahila Ayyavoo, MBBS, from the University of Auckland in New Zealand, and colleagues examined whether birth order correlates with changes in metabolism in childhood in a study involving 85 healthy prepubertal children (ages 4–11 years, born at appropriate birth weight at 38–40 weeks of gestation). Of the participants, 32 were first-born and 53 were later-born children. The children underwent clinical assessments, 24-hour ambulatory blood pressure monitoring, and intravenous glucose tests with Bergman’s minimal model.

The researchers found that, compared with later-born children, first-born children were significantly taller, by approximately 3cm, and were significantly slimmer. First-born children also had a 27% increase in insulin-like growth factor-1 concentrations, consistent with their taller stature. First-borns had a 21% reduction in insulin sensitivity compared with later-borns and had significantly higher daytime systolic and diastolic blood pressure upon 24-hour ambulatory blood pressure monitoring. Birth order was not associated with blood lipids.

“First-borns may be at a greater risk of metabolic and cardiovascular diseases in adult life,” the authors write. “This finding may have important public health implications, in light of a worldwide trend toward smaller families.”

Abstract
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