A recent Chinese University study of more than 100 children with a sleep disorder found that surgery at an early age can help prevent serious conditions from developing as they get older.

The research team said obstructive sleep apnoea affects five percent of primary school children in Hong Kong. They said it can be caused when the tonsils and adenoids, which are part of a ring of lymphatic tissue in the back of the throat and nose, become too large and block their breathing.

Signs of the problem include snoring, night sweats and breathing through the mouth.

Chinese University Professor of Paediatrics Albert Martin Li, who led the research, said the problem could make it difficult for children to pay attention and behave properly.

If it's not treated, he said, it could even lead to heart and blood pressure problems when they grow up.

Li said the surgery would remove any enlarged lymphatic tissue that blocked their breathing. "The symptoms are much better. And for blood pressure, we see those with more severe disease, their blood pressure comes down after surgery," he said.

However, he said not all children with the problem need surgery, as it works better for those who have larger tonsils or adenoids, or more severe symptoms.

Another researcher, Dr Kate Chan, mentioned that it's important for children to eat well and exercise regularly to help control their weight, which can also help manage this condition.