Is there such a thing as "Near-miss SIDS", "Near SIDS", and "Aborted SIDS"?

This is a difficult area.

By definition, SIDS babies died, and could not be revived (if there was a chance to try).

By definition, ALTE (apparent life-threatening event) babies, also called apnea of infancy or babies with unexplained apnea, did not die, and were able to be revived.

The terms "Near-miss SIDS", "Near SIDS", and "Aborted SIDS" have been used in the past, and refer to ALTE. These terms are not preferred now because they imply that if someone had not come along (by chance) to resuscitate an ALTE baby, the baby would have gone on to die. For those of you who may have witnessed an ALTE, they are frightening to the observer, who often 'believes' that the baby is in the process of dying. However, many ALTE babies have a number of episodes, which they manage to survive, sometimes even before they receive treatment, such as a home monitor. SIDS babies, on the other hand, rarely had apneas observed prior to death, and death is usually the first sign of any "problem". Therefore, I believe that the two populations are generally different, but possibly similar. The relationship might best be described as two overlapping circles, with the area of overlap being small. Some SIDS babies had apneas observed prior to death, though the percent is very small. Some ALTE babies will go on to die from "SIDS" (sudden death, no cause at autopsy), though the percent is small, even if they are not treated.

Doctor Guntheroth's other point, however, may be valid. If one wishes to study physiology, that is the way babies' organ systems behave, you need to study living babies. You can not do physiology on SIDS victims. So, which babies do you study? Many researchers, including our group, take babies who are statistically at high risk for SIDS, and compare various responses to low risk babies (controls). We have also used ALTE babies in many of these studies. This is not to say that ALTE = SIDS. But, rather, it says that these babies may have some similarities to the way SIDS babies would have behaved, and study of them might give us insights into SIDS. Everyone who does this type of research is acutely aware that we are not really studying SIDS, but only babies who we think might act like SIDS babies would have acted if they were alive.

Thank you.

Tom Keens
Children's Hospital Los Angeles

The term "near miss for SIDS" had its beginning in the early 1970s, following Dr. Steinschneider's report (Pediatrics 50:646, 1972) that several infants had died of SIDS after exhibiting breathing pauses (apnea) in sleep laboratory studies. As a result of these observations, the "apnea hypothesis" for SIDS was proposed and became the basis for many clinical investigations focused on finding the cause of SIDS and the possibility of finding a screening test that could identify infants at risk in order to prevent SIDS. The introduction and increase of home apnea/cardiac monitoring for prolonged apnea and/or heart slowing (bradycardia) detection as a possible prevention for SIDS occurred. Stanford University and many other centers around the U.S. began recruiting "near miss" SIDS infants for sleep and apnea studies. The "near miss" for SIDS term assumed that the event causing concern would have ended in a SIDS if the parent or caregiver were not there to intervene.

At the outset, many sincerely believed that the assumptions were correct, i.e., that the infant almost died and that the event might reoccur. It became common place to prescribe home monitoring. The emotional burden primarily for the families, and to a lessor extent for the medical and allied medical professional was considerable. Imagine the stress of having to react as if a SIDS was about to happen each time a monitor alarm sounded. Over time (ten to fifteen years), we learned that nearly all of the infants with "near miss" for SIDS survived and that the link between apnea and SIDS was not predictive for SIDS.

In 1987, the NIH consensus process on Infantile Apnea and Home Monitoring published a report stating that there were no scientific studies to support the conclusion that home monitoring prevented SIDS. Home monitoring was not recommended for siblings of SIDS, or newborn or preterm infants who did not have symptoms of apnea. The report also recommended that the term "near miss" for SIDS be retired since it was misleading and that there were no data to support that these infants usually died of SIDS. Instead the term "apparent life-threatening event (ALTE)" was introduced, which recognized that it may not be possible to determine whether or not the event could have lead to a death. The report estimated that approximately 7% of babies that died of SIDS had a history that suggested an observed ALTE. At this point, with additional experience and information, we have changed our position regarding "near miss" and its significance to SIDS. Hopefully this will end the public misconception, which in the final analysis, had more hazards than advantages.

What can parents do to lower the risk of SIDS? The answer has been stated in previous issues but it is worth saying again: do not smoke or use illicit drugs; do not allow anyone to smoke around your baby (passive smoke exposure); if it is possible, breastfeed your baby; unless instructed otherwise (by your doctor), place your infant on the back to sleep; finally, choose a firm mattress and do not use pillows or sheep skin in the baby's crib.

Article by: Ronald Ariagno, M.D., Stanford Medical School, Department of Pediatrics; Chairperson, Northern California Regional SIDS Council; Member, California State SIDS Advisory Council.

Reprinted with permission from Horizons, Vol. 1, No. 4, Spring/Summer 1995, California SIDS Program