[　Sudden Infant Death Syndrome (SIDS)　]

Sudden Infant Death Syndrome (SIDS) has been known as the unexpected sudden death of a healthy infant without a history of disease.

Definition

SIDS is defined as "a syndrome which brings a healthy infant sudden death that is unpredictable from his/her health condition or history of diseases, and cannot be clarified for etiology by the condition of death or autopsy findings.

(Report of the MHW Research Group on the Mentally and Physically Handicapped, 1994)

Incidence

It has been known that the nursing environment for infants gives an important influence on the incidence of SIDS. In other countries, the incidence of SIDS has shown a remarkably decrease thanks to the Back to Sleep (BTS) campaign to avoid placing infants on the stomach during sleeping. In Japan, each year 600-700 infants die of SIDS, representing one in every 2,000 live births. However, the number of deaths from this syndrome has slightly decreased to 579 in 1995.

Etiology

Etiology of SIDS has not been confirmed yet. Many speculations, such as a delaying of arousal reaction, severe sleep-induced apnea, prematurity of infant, infections, narrowing of airway, have been considered as the caueses. In regard to the delaying of arousal reaction, respiratory inhibition brings oxygen deficiency(hypoxeia). Briefly, it has been considered that SIDS is not an accident, but is ascribable to respiro-circulatory dysfunction.

Risk Factors

It is known that incidences of SIDS differ between countries and districts. Such differences are seemed to be related to various nursing environments. Among those, next four factors are considered as potensial risk factors for SIDS in other countries. Those are (1) placing an infant on the stomach during sleep, (2) bottle-feeding, (3) smoking of parents, and (4) warming an infant excessively(over-heating). In Japan, however,, the fourth of the risk factors"warming an infant excessively"was excluded, and the following three cautions have been announced in order to reduce SIDS.

１） Lay your baby on supine. However, if lying prone is instructed by a physician for a medical reason, follow the instruction. ２） Stop smoking during pregnancy and around your baby. This caution must be also obeyed by his/her close relatives. ３） The breast-feeding is desirable for your baby. Although there is an individual difference in the amount of mother's milk, give mother's milk if possible. (from the Hand-Book for Mother and Baby, issued in 2000,Japan)

[　Problems of SIDS　]

SIDS includes many problems. The most important one is that the cause of this syndrome is still uncertain. The second problem is that the reason(s) and effect(s) of "over-heating" on SIDS have not been clear. And the third problem is that the bottle-feeding has been added in the "risk factors" for this syndrome, although there is no scientific evidence in the reration between the bottle-feeding and SIDS. Because, many mothers who need adding powdered-milk for thier babies are anxious against the bottle-feeding. In order to remove the anxiety of mothers against the bottle-feeding, especially only in a few days just after birth, it must be clarified the true cause of SIDS more scientifically.