A study just out in Pediatrics has many people trying to connect the dots between three seemingly unrelated issues: snoring, behavioral problems, and breastfeeding.
This prospective study looked at 250 Cincinnati children aged 2 to 3. The goal: to determine whether persistent snoring in this age group is associated with behavioral and cognitive problems, and to identify factors predictive of snoring. Persistent snoring was defined loud snoring (reported by parents) 2 or more times per week, at ages 2 and 3.
The findings? Persistent snoring was associated with higher rates of hyperactivity, depression, and attention problems.
The strongest predictors of snoring? Lower socioeconomic status and not breastfeeding or breastfeeding for a short period of time.
In fact, none of the 250 children who had breastfed for one year or more were persistent snorers, while nearly 25% of those who were not breastfed or breastfed for a month or less became persistent snorers.
The authors concluded: “We found that children who were fed breast milk, especially across longer periods, were at markedly lower risk for persistent snoring, even after controlling for potential confounding variables.”
The authors note that this finding is consistent with prior research:
Two epidemiologic studies that coded breastfeeding dichotomously reported similar findings, and a study of habitually snoring children found that longer duration of breastfeeding between 2 and 5 months of age was associated with greater protection from obstructive sleep apnea.
So, why would that be? The authors note:
Authors of the latter study speculated that the act of breastfeeding promoted the development of a healthy upper airway structure and that breast milk provided immunologic protection against infections that promote sleep disordered breathing.
This discussion reminded me of the late Dr. Brian Palmer, a dentist who devoted much attention to the question of breastfeeding and its relationship to normal development of the oral cavity and surrounding structures. As part of his investigation Dr. Palmer studied the skulls of humans born before the widespread use of bottles and pacifiers.
In this fascinating discussion of obstructive sleep apnea (OSA) and breastfeeding, he noted:
An article published in 1997 by a sleep research team from Stanford describes a formula for predicting OSA. It states that individuals with high palates, narrow dental arches, overjets (lower jaw retruded), and large necks who are overweight are at risk for OSA. The information is extremely significant when one realizes that evidence from skulls shows that before the invention of baby bottles and pacifiers, high palates, narrow dental arches, and overjets were rare.
A high palate can impact occlusion and breathing. It can also narrow the upper dental arch and cause a crossbite. Since the roof of the mouth is also the floor of the nose, any increase in the height of the palate decreases the volume size of the nasal chamber. This decreased size can then increase the air resistance through the nose. High palates also lead to a narrowing of the posterior nasal aperture or choanae (skull opening at the back of the nose). A smaller opening means a narrower opening into the soft tissue section of the airway.
How does the breast impact the normal development of these structures? Dr. Palmer wrote:
While the soft breast adapts to the shape of the infant’s mouth, anything firm requires the mouth to do the adapting. In addition, during breastfeeding, the tongue moves in a peristaltic motion underneath the breast. This motion is critical for the proper development of swallowing, alignment of the teeth, and the shaping of the hard palate.
Dr. Palmer noted that there are other factors which might have influenced these changes. But he concluded, “The best prevention (for OSA) is breastfeeding and keeping objects like pacifiers out of the mouth.”
The authors of this recent study might well agree.
Are your children snorers? Has breastfeeding had a discernible impact on your children’s sleep breathing or orofacial development? Has snoring had an impact on their behavior?