Sunday, January 27, 2008

Revisiting SIDS

If you are a younger parent, you've probably been exposed to the "Back To Sleep" campaign, which recommends putting infants to sleep on their backs.

This campaign has been hugely successful at reducing the incidence of SIDS - Sudden Infant Death Syndrome.

You might ask - why were parents putting infants to sleep on their tummies? Is that a traditional folk-way or something? No. It was modern medical advice, circa the 1950's:
Believers in stomach sleeping, including Dr. Benjamin Spock, preached that prone sleeping could prevent babies from choking on their own vomit or developing pneumonia caused by inhalation of vomit or foreign objects.
The reporter now casts this advice in religious terms: "believers" listened to one who "preached". But at the time, mothers thought they were acting according to sound scientific principles.

I lost an infant brother to SIDS. Francis was his name. He was sleeping on his stomach when he died. He had another major risk factor - he was a twin. So perhaps he would have died anyway.

Note that Dr. Spock & co. had a reasonable hypothesis. But should they really have been so definite in their advice giving?

I think when he preached,
He over-reached.

I suppose that susceptibility to fads is part of human nature. It has certainly been a part of human science. In the long run, it's self-correcting. But in the short-run, it can sometimes cut off your long-run.

Keep up your defenses
In the face of faddish consensus.

4 comments:

Anonymous said...

I recall hearing somewhere that back-sleeping babies were prone to develop flat-backed heads. The source of this I can't recall.

I also remember an article, and this from an academic source, that found belly sleepers to be somewhat more agile and athletic later in life, due to their inward-pointed toes.

Perhaps Dr. Spock saved us from legions of flat-headed klutzes?

John Enright said...

Yes. So now pediatricians are recommending that infants sleep on their backs, but play on their tummies.

Anonymous said...

SIDS deaths in the U.S. decreased from 4,895 in 1992 to 2,247 in 2004. But, during a similar time period, 1989 to 2004, SIDS being listed as the cause of death for sudden infant death (SID) decreased from 80% to 55%. According to Dr. John Kattwinkel, chairman of the Center for Disease Control (CDC) Special Task Force on SIDS "A lot of us are concerned that the rate (of SIDS) isn't decreasing significantly, but that a lot of it is just code shifting”.

In a 2006 letter to the editor in the Journal of Pediatrics Dr. Rafael Pelayo, Dr. Judith Owens, Dr. Jodi Mindell, and Dr. Stephen Sheldon asked the following question of the American Academy of Pediatrics Task Force on Sudden Infant Death Syndrome after their Pacifier and Co-sleeping report was published:
"...from the perspective of the field of pediatric sleep medicine, the policy statement's laudable but narrow focus on SIDS prevention raises a number of important issues that need to be addressed. In particular, the revised recommendations regarding cosleeping and pacifier use have the potential to lead to unintended consequences on both the sleep and the health of the infant. The potential implications of a SIDS risk-reduction strategy that is based on a combination of maintaining a low arousal threshold and reducing quiet (equivalent to Delta or slow-wave sleep) in infants must be considered. Because slow-wave sleep is considered the most restorative form of sleep and is believed to have a significant role in neurocognitive processes and learning, as well as in growth, what might be the neurodevelopmental consequences of chronically reducing deep sleep in the first critical 12 months of life?"

In a currently utilized model that explains the process in which slow wave sleep is involved in memory consolidation the hippocampus acts as a temporary storage facility for new memories which are then transferred to the neocortex during slow wave sleep (SWS) [8]. In this model, acetylcholine acts a feedback loop inhibitor inside the hippocampus during REM sleep and wakefulness. The activity during the high cholinergic wakefulness period is believed to provide an environment which allows for the encoding within the hippocampus of new declarative memories. The low cholinergic environment during SWS is thought to then allow these memories to be transferred from the temporary storage of the hippocampus to their permanent storage environment in the neocortex and for memory consolidation [9, 10].
A significant way of decreasing slow wave sleep in infants is by changing their sleeping position from prone to supine. It has been shown in studies of preterm infants [11, 12], full-term infants [13, 14], and older infants [15], that they have greater time periods of quiet sleep and also decreased time awake when they are positioned to sleep in the prone position.

8. Hasselmo, M.E. 1999. Neuromodulation: Acetylcholine and memory consolidation. Trends Cogn. Sci. 3: 351–359.
9. Buzsáki, G. 1989. Two-stage model of memory trace formation: A role for “noisy” brain states. Neuroscience 31: 551–570.
10. Hasselmo, M.E. 1999. Neuromodulation: Acetylcholine and memory consolidation. Trends Cogn. Sci. 3: 351–359.
11. Myers MM, Fifer WP, Schaeffer L, et al. Effects of sleeping position and time after feeding on the organization of sleep/wake states in prematurely born infants. Sleep 1998;21:343–9.
12. Sahni R, Saluja D, Schulze KF, et al. Quality of diet, body position, and time after feeding influence behavioral states in low birth weight infants. Pediatr Res 2002;52:399–404.
13. Brackbill Y, Douthitt TC, West H. Psychophysiologic effects in the neonate of prone versus supine placement. J Pediatr 1973;82:82–4.
14. Amemiya F, Vos JE, Prechtl HF. Effects of prone and supine position on heart rate, respiratory rate and motor activity in full term infants. Brain Dev 1991;3:148–54.
15. Kahn A, Rebuffat E, Sottiaux M, et al. Arousal induced by proximal esophageal reflux in infants. Sleep 1991;14:39–42.

John Enright said...

anonymous, thank you!