Overweight children at risk of a new ‘beast,’ doctors warn: Obesity hypoventilation syndrome

Canadian doctors are warning of yet another serious but hidden complication of obesity in children that, if untreated, can be fatal.

“Obesity hypoventilation syndrome,” or OHS, occurs when fat tissue lodges in the upper airways, affecting a child’s day and nighttime breathing. The result is too little oxygen and too much carbon dioxide in the blood.

Major complications can include congestive heart failure, respiratory failure and death.

Yet the syndrome is “almost certainly under-recognized and under-reported” in children, doctors from the University of Ottawa, University of Toronto, University of Alberta, Canadian Paediatric Society and Public Health Agency of Canada write in this month’s issue of the journal, Paediatrics & Child Health.

In Canada, obesity rates among children and adolescents have almost tripled in the past 25 years, the authors note in their report, “Obesity hypoventilation syndrome: A different beast.” Today, “approximately 26 per cent of Canadian children two to 17 years of age are overweight or obese.”

Children with chronic hypoventilation don’t sleep well at night and are excessively drowsy during the day. That fragmented sleep can affect concentration, attention and intellectual functioning, says Dr. Danielle Grenier, a community pediatrician in Gatineau, Que.

Researchers with the Canadian Paediatric Surveillance Program have launched a two-year study to estimate the frequency of OHS and increase awareness among pediatricians. Doctors are being urged to report any new cases in children and youth under 18.

“Imagine if you have a child that doesn’t sleep well, and not only you don’t sleep well, you don’t oxygenate your brain well,” said Grenier, director of medical affairs for the Canadian Paediatric Society. “Some of these children can have learning difficulties because they’re so sleepy, and because they’re not able to concentrate.”

In severe cases, hemoglobin, the oxygen-carrying protein in red blood cells, thickens, forcing the heart to work harder and increasing the risk of congestive heart failure.

Some children will need ventilators to support their breathing at night, Grenier said.

“We want to make sure that we know how much of this is happening in Canada, and that these children are detected early and get help with their diet and physical activity to bring them back to a healthy weight.”

A study of obese children in Belgium found 19 per cent with mild to severe obstructive sleep apnea, where children stop breathing temporarily during sleep.

“To me, any child that is obese and has sleeping and breathing problems is serious,” Grenier said.

Obesity in children is not only increasing, but “we’re seeing them at a younger and younger age,” she added.

Doctors in Canada are now treating obese 13-year-olds with Type 2 diabetes and “persistent albuminuria,” an early sign of diabetic kidney disease, according to data from the pediatric surveillance program.

“It means their kidneys are having a hard time,” Grenier said. “When you start seeing that in children, it’s not good news. In the long run, it’s renal (kidney) failure and hemodialysis.”

Once only ever diagnosed in adults, Type 2 diabetes is being diagnosed in children under 10.

Grenier said many of the parents she sees in her office don’t understand what a “normal” food portion means. “They think if one juice is good, 10 are better. If milk is good, you can have as much as you want in a day.

“These are basic, basic principles …. This is the teaching we do every single day in the office. Once you see (a child’s) BMI increasing and you see that it’s not muscle, it’s all subcutaneous fat, you have to get the whole family involved that a Coke is full of sugar and it’s not the best treat for a child,” Grenier said.

“Veggies and fruits are better. Water is better. But that message is hard to get across.”