Sunday, November 12, 2006

SIDS and Seratonin

When our oldest son died in 1963, we were told his sudden, unexplained illness was "crib death." After pushing the pathology report across the desk of more doctors than I care to remember, I was told that it was an overwhelming viral pneumonia which can kill even adults if the immune system happens to be briefly impaired. Meanwhile, the medical community came up with a term for babies that go to bed healthy and never wake up--"sudden infant death syndrome," or SIDS. The new name didn't help much, and the causes of SIDS remain unknown, almost 45 years later.

Even though I know that our son's pneumonia was not within the SIDS range of causes, I've always kept my eye on the research, because the horror and emptiness of suddently losing a child gives me common ground with parents of SIDS babies. And although there have been major break throughs in all manner of diseases, and new diseases have cropped up we'd never heard of in the 60s (change the letter S to an A, for instance), there are still no answers for SIDS.

So I read with interest "Multiple serotonergic brainstem abnormalities in Sudden Infant Death Syndrome," in a recent JAMA (vol 296, no. 17, p. 2124) about research that links levels of seratonin in the brain which influences breathing, cardiovascular system, temperature and the sleep-wake cycle and sudden death. The editorial writer (p. 2143) praised the research in this field, done both in Japan and the U.S., but quickly wanted to move on to racial and socio-economic factors. There is a higher incidence of SIDS among African-Americans, Hispanics, Native Americans, but particularly boys. Also, there have been aggressive "back to sleep" education programs to teach parents not to put babies down to sleep on their tummies, or in a bed with someone else, or exposing them to cigarette smoke. The rate of SIDS has gone down since the implementation of sleep safety programs.

Unfortunately, the controls used in SIDS research are children who have died of other causes--diseases, accidents, or trauma. And the SIDS babies data comes only from those parents who have allowed tissue samples to be used from their dead child. So this skews the results right there (in my opinion) because only California has a law that renders it unnecessary to obtain informed consent from the individual parents if tissue samples from their child are to be used for research on SIDS. So you've got a small group to start with (2162 infants died of SIDS in the US in 2003), with a pretty small sample, from a rather narrow geographic area.

I know nothing about medical statistics or how to figure risk factors or statistical anaysis. I could barely make my way through the "density of medullary 5-Ht neurons." However, I'm not in favor of parents being required by law to submit samples, or even have an autopsy, so we can have a more diverse racial data base. It's quite possible that most grieving parents will want as much knowledge as possible and many will want their child's death to make a contribution to science, but when laws are passed requiring you to take part in medical research, we've gone too far.


Anonymous said...

Hi Norma,
I have never had to face the harsh reality of losing a child (thank God), but I've always been interested in the cause of SIDS.
Over the years I've read that mattresses could be suspect...the PVC in the material which are made with phosphorus and arsenic to help make them more flame resistant (don't know about that though because most babies begin with a brand new mattress). I guess it begins to decompose shortly after it was manufactured.
I've read too that theres a link between vaccinations and SIDS (autism as well).
This new study is another piece of the puzzel.

So sorry for the loss of your child.

Anonymous said...

This is the second try at this comment -- the first one produced an error. If two come up, I apologize.

The thing to remember is that SIDS is not a disease. It is a syndrome, which is just a cluster of signs an symptoms -- in this case, just the death of an infant without explanation. It's a little like "headache of unknown cause." A researcher might come along and find out that brain tumors can cause headaches. Thus, people with brain tumors and headaches will have the headaches attributed to the tumor, not "unkknown cause." Another researcher might find that stress can cause headaches. Another might find that drinking cold drinks can cause headaches, etc.

In the case of SIDS, as different causes of infant death are discovered, those cases are recategorized. The actual rate of infant death may not change a lot (and it really has been a modest change). The only difference is that the deaths are categorized differently. For instance, my office no longer calls deaths in which the child is placed prone in soft bedding as SIDS. They are called "sudden unexpected infant death (SUID) in the presence of prone position." Similarly, deaths in which there is cosleeping are categorized as "SUID in the presence of cosleeping." Thus the great "decrease" in SIDS is not due to a great decrease in death (though the "back to sleep" program *has* helped a lot), but to a change in nomenclature.

Finally, I have to say that I disagree with your statement about autopsies (as you might expect). To me, it's a little like vaccination and floridation. The public health benefits far outweigh what are, essentially, aesthetic complaints. Autopsies for natural disease do not usually preclude open-casket funerals or delay funeral proceedings. They certainly don't hurt the dead person. The question then boils down to how many thousand people are we willing to have die for an aesthetic objection?

Anonymous said...

I had a cousin who died of cot death
and I saw the news item too. I found it interesting as there is a history of depression and anxiety in our family. The levels of seratonin contribute to depression and now cot death which makes me wonder if there is a link.

My prayers and thoughts are with you today

Wendy Ann Edwina D'Cunha e Pereira said...

Cot Death or SIDs or whatever they might call it is every mother's nightmare... I guess it was something that really frightened me a lot when I was expecting both my kids... The worst is there are really no explanations when it happens. They might find a 100 probable causes. But it really is something no one has been able to narrow down. The horror of it is something that will live with the parents an entire lifetime...