OBJECTIVES To describe sudden unexpected infant deaths (SUIDs) occurring in safe sleep environments and explore differences in selected characteristics. METHODS We examined SUID from 22 jurisdictions from 2011 to 2020 and classified them as unexplained, no unsafe sleep factors (U-NUSF). Data were derived from the Sudden Unexpected Infant Death and Sudden Death in the Young Case Registry, a population-based Centers for Disease Control and Prevention surveillance system built on the National Center for Fatality Review and Prevention's child death review program. SUID classified as U-NUSF included infants who were (1) awake, under supervision, and witnessed to become unresponsive or (2) found unresponsive in a safe sleep environment after sleep (unwitnessed). We calculated frequencies and percentages for demographics, birth and environmental characteristics, medical history, and death investigation findings. RESULTS Most of the 117 U-NUSF SUID occurred before 4 months of age. Witnessed deaths most commonly occurred at <1 month of age (28%), whereas unwitnessed deaths most commonly occurred at ages 2 to 3 months (44%) Among all U-NUSF, 69% occurred in the infant's home (62% witnessed, 77% unwitnessed). All unwitnessed deaths occurred in a crib; most witnessed deaths occurred while being held (54%) or in a car seat traveling (18%). Most infants (84%) had no history of abuse or neglect. Abnormal autopsy findings were reported in 46% of deaths (49% witnessed, 42% unwitnessed). CONCLUSIONS Characterizing these deaths is key to advancing our knowledge of SUID etiology. Our study revealed a heterogeneous group of infants, suggesting physiologic, genetic, or environmental etiologies.

中文翻译：

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没有不安全睡眠因素的不明原因婴儿死亡：2011 年至 2020 年。


目的 描述在安全睡眠环境中发生的婴儿意外猝死 （SUID），并探讨选定特征的差异。方法 我们检查了 2011 年至 2020 年来自 22 个司法管辖区的 SUID，并将其归类为无法解释的、无不安全的睡眠因素 （U-NUSF）。数据来自婴儿意外猝死和年轻病例登记处猝死，这是一个基于人群的疾病控制和预防中心监测系统，建立在美国国家死亡审查和预防中心的儿童死亡审查计划之上。归类为 U-NUSF 的 SUID 包括 （1） 清醒、在监督下并目睹变得无反应或 （2） 在睡眠后在安全睡眠环境中发现无反应（无目击者）的婴儿。我们计算了人口统计学、出生和环境特征、病史和死亡调查结果的频率和百分比。结果 117 例 U-NUSF SUID 中的大多数发生在 4 个月之前。目击死亡最常见于 <1 个月大 （28%），而无目击死亡最常见于 2 至 3 个月大 （44%）。在所有 U-NUSF 中，69% 发生在婴儿家中（62% 有目击者，77% 无目击者）。所有未目击的死亡都发生在婴儿床上;大多数目击者死亡发生在被关押 （54%） 或坐在汽车座椅上旅行 （18%） 时。大多数婴儿 （84%） 没有虐待或忽视的历史。据报道，46% 的死亡患者尸检结果异常 （49% 有目击者，42% 无目击者）。结论 描述这些死亡的特征是提高我们对 SUID 病因学了解的关键。我们的研究揭示了一组异质性的婴儿，提示生理、遗传或环境病因。