MONDAY, April 16, 2007 (HealthDay News) -- Scientists in South Korea have uncovered a possible connection between body fat in children and a certain kind of ear infection, but several specialists in the United States are expressing doubts about the research.
If the link does exist, however, it could provide doctors with yet another indication of how extra fat is bad for kids just as it is for adults. "We have to pay close attention to decrease childhood obesity," said study co-author Dr. Seung Geun Yeo, a researcher at Kyung Hee University in Seoul.
Ear infections in children remain very common, affecting as many as eight or nine of every 10 kids. Doctors blame the middle ear, which often cannot fully drain fluid as it is developing.
Doctors typically prescribe antibiotics, although there is concern that the germs are developing immunity to them.
In the new study, the researchers looked at two groups of children aged 2 to 7 -- 155 who had tubes implanted in their ears to help them drain fluid and recover from ear infections, and 118 who were in the hospital for other reasons.
Technically, the children suffered from a form of ear infection known as otitis media with effusion. Some of the symptoms of ear infections, including ear ache and fever, aren't present when this condition occurs.
The children who were treated for ear infections were fatter than the other children, based on their body mass index (BMI), a ratio of weight to height.
According to the study, the children with ear infections had an average BMI of 22, compared to 16 for the other group. This suggests that extra fat boosts the risk of ear infections.
Total cholesterol was also higher in the children with ear infections.
The researchers also looked at the children with ear infections specifically and divided them into fatter and thinner children. They didn't find any indication that being fatter made kids more likely to have more drainage tubes inserted.
The study was published in the April issue of Archives of Otolaryngology-Head & Neck Surgery.
Two American ear, nose and throat specialists said they weren't impressed with the South Korean study.
Dr. Jack Paradise, professor of pediatrics and otolaryngology at the University of Pittsburgh School of Medicine, said one "glaring" problem was that the researchers weren't comparing similar groups of children to each other. Among other things, he said, the study didn't look at the socioeconomic levels of the children -- a major factor in the development of ear infections -- or factors like exposure to other children or the season of the year -- infections are more common in winter.
Paradise added that it's difficult to generalize medical trends by simply looking at hospital records, because there are so many factors that affect whether children have tubes put in their ears. These can include everything from parents' sensitivity to their children's symptoms to accessibility of health care, he said.
Dr. David Darrow, of Children's Hospital of The King's Daughters in Norfolk, Va., noted that the study authors never offered a theory about why obesity might be connected to ear infections. The research "lacks a physiological explanation for the conclusion," he said.
In fact, said Paradise, a connection between obesity and ear infections is "not biologically plausible."
However, Dr. Jordan S. Josephson, an otolaryngologist at Lenox Hill Hospital in New York City and author of Sinus Relief Now, said it's possible that childhood obesity may be associated with ear infections.
"Obesity, as we know, causes people to have a large appearance outwardly, but what most people do not realize is that when people gain weight, their internal spaces get crowded by the bulk of the weight that we put on," he said in a prepared statement. "That means that their eustachian tubes that drain their ears are narrowed, and that can lead to otitis media with effusion. Even worse, as the diameter of their nose and airway is reduced, these people can develop snoring and sleep apnea."
In an interview, study co-author Yeo said some research has suggested a link between obesity and inflammation, and that could be a possible cause. But he acknowledged that the possible connection between obesity and ear infections remains to be explained.
For more on middle ear infections, visit the Nemours Foundation.