Obese child
Obese and severely obese boys run a significantly higher risk of developing gallstones than their lighter peers. Credit: Wikimedia Commons Wikimedia Commons

Children and adolescents who are obese or overweight are more likely to suffer gallstones than children with a normal body mass index, according to new research.

Researchers found that overweight children were twice as likely to develop gallstones, while moderately obese children have a four times higher risk of developing gallstones and extremely obese children are six times as likely to have gallstones. Overweight and obese girls were more likely to have gallstones than boys.

Gallstones are hard, stone-like deposits that form in the gall bladder from components of bile. Adults over the age of 40 are normally the most susceptible.

"Although gallstones are relatively common in obese adults, gallstones in children and adolescents have been historically rare. These findings add to an alarming trend ­- youth who are obese or extremely obese are more likely to have diseases we normally think of as adult conditions," said Corinna Koebnick, researcher at the Kaiser Permanente Southern California Department of Research & Evaluation.

The discovery was based on the electronic health records of more than 510,000 children aged between 10 and 19 from Kaiser Permanente Southern California.

The study found that girls who are obese and extremely obese are six and eight times more likely, respectively, to have gallstones than girls who are underweight or of normal weight. Obese and severely obese boys are more than twice and three times as likely to have gallstones compared to their peers, according to the findings published in the Journal of Pediatric Gastroenterology & Nutrition.

Gallstones affect nearly 20 million adults in the US. Symptoms of gallstones include recurrent abdominal pain, fever and nausea.

"The high rate of gallstones in obese children and adolescents may surprise paediatricians because gallstone disease is generally regarded as an adult disorder. Since obesity is so common, paediatricians must learn to recognise the characteristic symptoms of gallstones," said George Longstreth, gastroenterologist from Kaiser Permanente San Diego Medical Centre.

"With increasing numbers of cases of gallstones in children, we wanted to better understand the potential role of risk factors such as obesity, gender, ethnicity, and oral contraceptive use. With childhood obesity on the rise, paediatricians can expect to diagnose and treat an increasing number of children affected by gallstone disease. It is important to identify other factors that increase risk as well," said Koebnick.