Insulin less effective in first-born children

First-born children may be at greater risk of developing diabetes or high blood pressure in later life than later-born kids, according to new research.
The study found that first-born children have reduced sensitivity to the hormone insulin and higher daytime blood pressure than kids who have older siblings.
Low insulin sensitivity, also referred to as insulin resistance, is a risk factor for type 2 diabetes, but it can also lead to number of other health problems, including high blood pressure (hypertension), obesity, heart disease and heart failure .
Researchers at the University of Auckland’s Liggins Institute in New Zealand measured fasting lipid and hormonal profiles, as well as height, weight and body composition, in 85 healthy children aged 4 to 11. They explained that children were focused on because puberty and adult lifestyle can affect the effectiveness of insulin.
Of the 85 child participants, 32 were first-born children and the results showed this group had a 21% reduction in insulin sensitivity and a 4 mmHg increase in blood pressure.
“Although birth order alone is not a predictor of metabolic or cardiovascular disease, being the first-born child in a family can contribute to a person’s overall risk,” said Wayne Cutfield, of the University of Auckland.
He added that more research is needed to determine how these risk factors for first-born children translate into adult cases of diabetes, hypertension and other conditions.
The study, which is the first to report a significant decline in insulin sensitivity among first-born children, will appear in the March 2013 issue of Journal of Clinical Endocrinology and Metabolism (JCEM).