The quest for the mechanisms of the sudden infant death syndrome: Doubts and progress

Abstract

After the many epidemiologic and pathologic studies, the last decade is witnessing the first large prospective studies designed to test specific mechanisms proposed for SIDS. The respiratory and the cardiac mechanisms are not mutually exclusive and seem to be the largest contributors to the whole of SIDS, even if their respective importance still remains to be quantified. It would be logical to concentrate the research efforts on answering this question before investigating extensively other less likely possibilities. The concepts and data presented here indicate that the sympathetic imbalance hypothesis, although not yet proven, has gained plausibility on the basis of current knowledge. The potential for early identification of some future SIDS victims and the likelihood, if the hypothesis is correct, of developing an effective and safe preventive strategy make even more necessary an accurate and unbiased evaluation of the cardiac hypothesis.