Deep down, we knew this was going to be a rough winter. But, DANG! It has been a REALLY rough winter. It’s our first winter living back in the north, after moving from Texas to Pennsylvania last April, and it’s TheMiniB’s first year in an institutional day care center. It’s a wicked combination that has resulted in a new viral infection sweeping through our household just about every other week. Combine that with a toddler who is finishing up his teething phase, and you’ve got a recipe for the dreaded ear infections!
Otitis media is the clinical term for an ear infection and poor TheMiniB has been plagued with ear infections just about once per month this entire winter. As four ear infections in one year (or three infections in a six-month period) can be enough for a chronic ear infection diagnosis, and we were just diagnosed with our 3rd (or was it our 4th?) infection this year, I am expecting my pediatrician to have a sit-down with me at our 3-week post-infection follow-up. Not surprisingly, the thought of ear tubes has been floating around in my mind. As I know several other parents who are also thinking a lot about ear tubes, a recent publication in the journal, Physiology and Behavior, is well-timed. Titled, ‘Otitis media and associations with overweight status in toddlers,’ this study investigates the hypothesis that the number of ear infections, and especially getting tubes in one’s ears, will be associated with being overweight at age two. It also considers the reverse hypothesis that being overweight in infancy will predispose individuals to recurrent ear infections.
I had actually never heard of an association between ear infections, tubes, and childhood obesity. However, the authors of this study do provide several supportive references. Although an exact reason for the association is not entirely clear, there is a nerve called the Chorda Tympani Nerve (CT) that sends information about taste from the tongue to the brain. Think of this nerve as a wire, like the wires that send information from the cable company to your TV. Well, this wire needs to have a path to get from the tongue to the brain, and it just so happens that the path of the CT nerve goes RIGHT THROUGH THE MIDDLE EAR! So, one current theory is that inflammation due to chronic ear infections and/or ear tube surgery results in damage to the CT nerve, which changes the way kids perceive taste, which leads to them having a strong preference for sweet and fatty foods, which ultimately alters their food intake in an unhealthy way.
Data for this publication came from a study that followed a group of children from birth to age two, and was designed to investigate predictors for early onset of ear infections. Scientists kept track of childrens’ ear infections, ear tube placement, and hearing ability. Length and weight were also recorded at two-month and two-year well-child visits, and children were categorized based on their weight-for-length (WFL) percentile. For example, if a child weighed more than 85% of kids their same height, that child was categorized as overweight. Similarly, if a child weighed more than 95% of kids their same height, that child was categorized as obese.
After controlling for factors which might influence their conclusions, such as breastfeeding history, day care attendance, birth weight/length, and maternal smoking, the scientists report a statistically significant relationship between ear tube placement and being overweight or obese at age two. However, simply having chronic ear infections without tube placement was not associated with weight status. This means that kids who had tubes placed in their ears before turning two were likely to weigh more than 85% of children their same height.
Interestingly, the reverse hypothesis that being overweight in infancy will predispose individuals to recurrent ear infections was NOT supported by the data collected in this study. Being >85th percentile WFL at two months of age had no bearing on the number or frequency of ear infections, nor did it have any bearing on the frequency of tube placement. This means that if you have a big baby, you are not destined to have lots of ear infections in your future!
I feel it is important to stress that this study was not designed to determine WHY kids with ear tubes tend to be overweight by age two. Current theories that the CT nerve are somehow involved are, at this point, still just theories. Even the authors of this study admit that, while they tried their best to take into consideration all of the variables they could think of that might interfere with their statistical analysis, there could still be variables out there that they did not consider. If you, reader, have any insight into potential confounding variables based on your parental experience, I encourage you to post a comment and we can discuss whether or not the authors took this variable into consideration.
Of course, before you freak out because you just had tubes placed in your kid’s ears, please understand that this does not mean that ALL kids who had tubes in their ears were overweight at their two-year well-child visit. However, what IS clear from this study is that weight gain could be a potential side-effect of ear tube placement. Parents need to be aware of this association and take it into consideration when making decisions for their child’s well-being. At the very least, if a parent believes that ear tubes are in the best interest for their child they might keep in mind this association and actively limit their child’s exposure to sugary/fatty foods while providing an abundance of nutrient-dense foods.
I encourage readers to comment on their opinions of this study, my summary, and their own experiences with ear tubes and/or childhood obesity.
Scientific Parenting 