A narrative review of sudden infant death syndrome: pathophysiology, risk factors, and prevention.

UNLABELLED: Despite increasing public awareness and clinical advances, sudden infant death syndrome (SIDS) continues to account for a substantial proportion of these deaths, largely due to limited mechanistic understanding. This knowledge gap underscores the need for in-depth investigation and population-specific prevention strategies. In this review, we synthesize current knowledge and recent advances in SIDS epidemiology, key demographic and clinical characteristics, and underlying pathophysiology. We discuss intrinsic and extrinsic risk factors within the triple-risk model, including brainstem and autonomic dysfunction, disordered arousal and cardiorespiratory control, susceptibility to lethal arrhythmias, and the contribution of infectious and inflammatory pathways. Finally, we provide an overview of evidence-based preventive measures and highlight future research directions for SIDS. CONCLUSION: Although substantial investigation is still required to elucidate the mechanisms underlying SIDS, the incidence may be reduced through the mitigation of both extrinsic and intrinsic risk factors. WHAT IS KNOWN: • SIDS accounts for a substantial proportion of postneonatal mortality. • A triple-risk model of SIDS. WHAT IS NEW: • New evidence of extrinsic and intrinsic risk factors associated with SIDS. • We propose preventive strategies for SIDS.