Hypoventilation and SIDS

Date: Wed, 21 Jul 1999

I have read a lot of your online articles on SIDS. I admire and appreciate your ability to carefully analyze and think through the data. I have a question that I hope you can answer for me as I am not a doctor. With all the information we have on SIDS why is it still called a mystery and not a hypoventilation syndrome?

The cause of SIDS remains unknown. Quite a bit of research has been ongoing for 30-years suggesting that SIDS may be due to some abnormality in breathing during sleep. However, this is not proven. In fact, early theories suggested that SIDS was due to babies simply stopping breathing during sleep (Apnea). We now know that SIDS is not that simple. All babies have pauses in their breathing during sleep, but the vast majority do not die. So, there must be others things involved. It may well turn out that SIDS is somehow related to inadequate breathing during sleep, in which case calling it a hypoventilation syndrome may be accurate. However, we are a long way from understanding how SIDS occurs. There are other theories besides this. In the end, we will just have to wait until research finds the answer. In addition, it would be an error to prematurely call SIDS a hypoventilation syndrome, because it might narrow the research focus. Therefore, it is best not to assume information we are not sure of, and to keep SIDS "open" as a mystery in hopes of attracting the best research minds form all disciplines to help us find the answer.

I hope this helps. Thank you.
---Tom Keens, tkeens@CHLA.USC.EDU
Childrens Hospital Los Angeles