Saturday, October 29, 2011

SIDS, Sleep Apnea, and Austism…Oh My!


One of the biggest problems that I have with the “Back to Sleep” campaign is that it uses statistics to prove its point that have no relevance to the actual campaign. SIDS cases were declining BEFORE the Back to Sleep campaign at the same rate that they began declining after it. Many people use the “after” numbers to prove that the campaign has been effective when, in fact, it might just be due to better prenatal care and other outside influences.

I came across a great blog entry where someone broke down those statistics. While I don’t agree with all of it, I applaud the person who took the time to write an intelligent entry with facts to back it up. You can find that complete entry here: http://www.heracliteanriver.com/?p=97 

In finding this person’s blog, I also uncovered some other startling statistics. For instance, I wasn’t aware that cases of autism have increased since pediatricians began encouraging parents to place their infants on their backs, or that cases of acid reflux have increased.

Honestly, when we first found Toby my initial thought was that he had choked on his sleep and died that way. His acid reflux was so bad that I actually researched it for days leading up to his death and was very concerned. I have met a couple of parents who did lose their babies this way and the deaths were initially labeled “SIDS” although they were later changed after the autopsies. I have woken Iris up on multiple occasions when her Snuza went off after a choking spell so acid reflux is more than just an inconvenience.

I, myself, often wonder HOW putting the infant to sleep on its stomach helps “prevent” SIDS. I am not the only one.

(ref) “It’s actually quite difficult to find good information on the exact risk of sleeping on the stomach, even though numerous studies have been done.  The lack of information on relative risk is so jarring that I really do wonder if it is deliberately omitted for fear that if parents made an informed choice, they wouldn’t necessarily follow the recommendation.  When statistics are given, they are sometimes exaggerated or given in such a way as to be misleading.” 

Yes, the statistics are misleading. Since there is nothing referred to as “near SIDS” anymore (I’m sorry, the “D” in SIDS stands for “death”) how can they possibly say that those who slept on their tummies are more likely to die of SIDS since they are either a) still alive or b) gone but their COD is a term of exclusion rather than an actual cause?

There are lots of parents who state that their babies died after rolling over onto their stomachs for the first time. Or, that they passed away at daycare and were found in a different position than what they were used to. So how do these statistics work? This blogger has a theory and I might buy it:

“Studies have shown that babies who only sleep on their backs don’t develop the skills they need to breathe properly when slept on their stomachs, so a baby consistently slept on his back has a greatly increased risk of dying when he is placed on his stomach to sleep or flips himself (as all infants eventually start to do).  Infants are much more likely to die of SIDS in their first week of daycare than just about any other time.  (Another statistic often quoted.)  Why?  Often because they are put to sleep in a way they aren’t used to.”

I really do believe that babies are meant to sleep on their tummies. Many doctors agree that if the infant has acid reflux, or just won’t stay on their backs, then their bodies are telling them something and you shouldn’t force them to sleep in that position. It has also been proven that the voice box is further up when they are infants and gradually drops down, more or less. As the infant ages, this could obstruct their breathing if they are on their backs.

So if this theory is correct, and it sounds as good as any, then it’s not putting them on their tummies that’s bad-it’s getting them used to an unnatural position (their backs) which interferes with their breathing when they do manage to turn over on their tummies.

If you don’t want to read that entire blog entry that I linked to, then at least read this part. It explains why SIDS statistics might be skewed and how this could be a bad thing in terms of interpretation:

“If you want a number that people understand intuitively, you generally use “relative risk.”  Say the rate of getting a particular cancer when you eat a healthy diet is 1 in 1000.  Say the rate of getting that cancer when you eat non-healthy food X is 3 in 1000.  I might therefore say, “You have three times the chance of dying of cancer by eating X,” which is a relative risk ratio of 3:1, or simply 3.  We intuitively understand what that means.
But SIDS studies rarely report relative risk.  Instead, they use a more abstract measure called “odds ratio,” although some researchers seem to confuse the terms and mistakenly call them risk ratios or something.  It’s a little bit difficult to explain “odds ratios” in a simple way, but basically they always show the same correlation as “relative risk,” except with a different magnitude.  That is to say, if the risks are equal for conditions A and B, the odds ratio and the relative risk will both be 1:1, or simply 1.  If condition A has a greater risk than B, both the odds ratio and relative risk will be greater than 1.  If the reverse is true, they’d be less than 1.
The problem with odds ratios is that they don’t correspond in size to relative risk, and under certain conditions they can greatly exaggerate a particular trend.  For example, in our earlier example of a relative risk of 3 for eating food X and getting a kind of cancer, the odds ratio might be around 3, or it might be 6, or it might be even 9 or greater.  It all depends on a bunch of variables including how prevalent a condition is in a given population, how a control group is chosen, etc.  In simple terms, an odds ratio doesn’t easily allow you to compare the exact risks in an intuitive way between two conditions.”

And for those of you that just think I am out to attack the “Back to Sleep” campaign, consider this:
“SIDS was also decreasing rapidly before the back-sleeping recommendation, mostly due to general improvements in infant health-care.  In the U.S., SIDS rates decreased by about 25% in the decade from 1982 to 1992, while 90% of infants still slept on their stomachs. “

In my eyes, 25% is not an insignificant number. There are many reasons why the number of cases decreased during that time. More women stopped smoking during pregnancy, prenatal care got better, newborn screenings started picking up more obscure health conditions, and SIDS got more notice which might have caused more parents to consider the risks of accidental suffocation (sometimes mislabeled as SIDS). You also have to consider the fact that the general reporting of SIDS as a COD changed in many states which might also have made the numbers go down.

For those of you that want actual numbers, they break down like this:

– about 1 in 1000-1500 prone-sleeping babies die of SIDS
– about 1 in 2000-3000 supine-sleeping babies die of SIDS

These are NOT significant numbers. Even the author agrees that “a relative risk less than 3 is generally considered insignificant enough that many major medical journals wouldn’t generally publish such research without a proven causal mechanism explaining the reason for the risk.”

The author states that “No matter what position, 999 of 1000 babies will be just fine.  If we randomly chose a sleeping position for infants, about 1/3 of SIDS deaths would still occur in babies on their backs.”

This is something that many pediatricians, researchers, and scientists are starting to agree upon, even though you wouldn’t know it by the number of posters, pamphlets, and talks regarding SIDS that you can find in hospitals and health departments.

The fact is, since we don’t know what SIDS is, I think it highly irresponsible to claim that one thing over another “causes” it. While there might be a correlation, we still don’t yet have a causation. With the numbers being so low, it might just be a coincidence.

The author states that since we don’t know what causes SIDS we really can’t say that sleeping on their stomachs caused their death. In fact, putting some babies on their backs might cause SIDS. The numbers are not that much different. Babies on their backs are at an increased risk for sleep apnea and not only has obstructive sleep apnea caused infant death, but it’s also been linked to SIDS.

I’m going to include the autism link here, not because I believe it myself, but because it was there and it’s not something I’d heard of myself:

“There are even people proposing possible links to the so-called “autism epidemic” of the past couple decades and this “Back to Sleep” campaign.  For various reasons dealing with changing diagnostic criteria, it’s difficult to estimate how much autism has actually increased versus how much it was simply not diagnosed before.  But most people seem to think it has increased at least somewhat, and it definitely follows the trend of the back-sleeping.  Both autism and SIDS have been linked to problems regulating seratonin levels.  Moreover, there’s a 4:1 male-female ratio in autism, which also happens to be the same 4:1 male-female ratio in babies who develop sleep apnea on their backs. “

And lastly, one of my favorite parts of the article had to do with the comparison of tummy sleeping to car accidents.

– Chances of a supine-sleeping infant succumbing to SIDS with no other risk factors: about 1 in 50,000 (range 25,000–60,000)
– Chances of the average person dying within the next year as a pedestrian involved in an accident: about 1 in 50,000

I know I’m simplifying things here, but when you think about it that way…There’s just as much of a chance of your infant dying of SIDS if you put them on their back as there is of you walking down the road and getting hit by a car and dying? I should point out that those statistics are for those infants that had no other risk factors.

For another similar view on this topic, you might check out this article, written by a physician who has his doubts about the back to sleep thing: http://doctorstevenpark.com/sids-back-sleeping-and-sleep-apnea

Again, I don’t know what any of this means but I was a little concerned to read that the campaign itself was based on an experiment and that there really hasn’t been any additional research to back it up, despite everyone going around talking about the benefits and how it reduces SIDS.

I felt obliged to include my thoughts on this in my blog because a recent discussion opened up concerning statistics in the support group and that spurred me to do my own research on it. Take it as you will, but hopefully it might spur your own hypotheses. Whether you agree or not, it’s definitely something to think about.

(Note: I thought that after losing Toby to SIDS I would be scared out of my mind and follow every precaution and advice out there. Instead, I seem to have gone in the opposite direction. I feel like I’ve played by the rules a lot and now I’m trying to find my own way in these things.)

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