Sudden unexpected infant death remains one of the most devastating outcomes in early childhood medicine, and a persistent assumption has been that risk factors are well-understood and declining. New data from New Zealand challenge that complacency, surfacing vaping as a probable emerging hazard — one that the research community has not yet adequately characterized.
Analysis of 101 coronial-identified SUDI cases from 2022–2023 in New Zealand found an overall rate of 0.87 per 1,000 live births, with starkly elevated rates among Māori infants (1.97/1,000) compared with Europeans (0.17/1,000). The sleep environment data are particularly striking: 72.3% of deaths occurred during direct bed-sharing. Maternal smoking was documented in 51.5% of cases, while vaping — a relatively newer exposure — appeared in 30.3%, with the combination of smoking and/or vaping present in nearly three-quarters of cases. Critically, vaping was statistically more prevalent in bed-sharing deaths than in non-bed-sharing deaths (p = 0.003), suggesting a possible interaction effect rather than vaping acting as an isolated variable.
This case series adds meaningful texture to a research landscape still catching up with the vaping transition. Prior SUDI literature firmly established prenatal and postnatal tobacco smoke exposure as a biological risk factor — likely through mechanisms involving nicotine's effects on infant arousal thresholds and cardiorespiratory control. Whether aerosol from e-cigarettes operates through similar nicotinic pathways, or introduces distinct toxicants affecting infant autonomic regulation, remains unresolved. The finding here is observational and case-series-based rather than drawn from a population-controlled cohort, meaning confounding — particularly by socioeconomic disadvantage, which co-occurs with both vaping and bed-sharing — cannot be excluded. The widening ethnic disparity over three historical comparison periods also points to structural determinants that biological research alone cannot address. For a field that thought its key risk factors were mapped, the vaping signal warrants urgent prospective investigation.