2026-07-07 東京科学大学
図1. 年次別のAHT入院発生率。乳児10万人あたりのAHT発生率は、有意な年次変化を示さず、横ばいで推移（P=0.91）
＜関連情報＞
- https://www.isct.ac.jp/ja/news/eeb8g06cq4fn#top
- https://www.sciencedirect.com/science/article/abs/pii/S0145213426002590
日本における乳幼児の虐待による頭部外傷による入院症例の発生率、2014年～2022年 Incidence of hospitalized abusive head trauma among infants in Japan, 2014–2022
Tomoki Kawahara, Yui Yamaoka, Kiyohide Fushimi, Takeo Fujiwara
Child Abuse & Neglect Available online: 30 May 2026
DOI:https://doi.org/10.1016/j.chiabu.2026.108139
Highlights
- Hospitalized AHT incidence in Japan was stable from 2014 to 2022.
- No significant increase in AHT occurred during the COVID-19 pandemic.
- Rising male childcare leave was not associated with reduced AHT rates.
- Current national prevention campaigns have not reduced AHT burden.
Abstract
Background
Abusive head trauma (AHT) is a leading cause of fatal maltreatment in infancy.
Objective
To estimate the annual incidence of hospitalized AHT among infants in Japan from 2014 to 2022 and assess the impact of the COVID-19 pandemic and increasing male childcare-leave uptake.
Participants and setting
Infants <1 year old admitted to hospitals participating in the nationwide Diagnosis Procedure Combination (DPC) database in Japan.
Methods
We conducted a retrospective study identifying AHT admissions using ICD-10 codes, and calculated annual incidence using census data. We compared pre-COVID-19 (2014–2019) and COVID-19 (2020−2022) periods and examined the ecological association between AHT incidence and national male childcare-leave uptake.
Results
We identified 755 presumptive and 5019 possible AHT admissions across 10.4 million infant-years. Presumptive AHT incidence was 7.9/100,000 in 2014 and 10.5/100,000 in 2022, demonstrating year-to-year variation but no significant overall trend (P for trend = 0.91). The incidence rate ratio for the COVID-19 period versus pre-COVID-19 was 0.95 (95% CI 0.81–1.12). No significant association was found between male childcare-leave uptake and AHT incidence (ρ = 0.15, P = 0.70).
Conclusions
Hospitalized AHT incidence in Japan did not change significantly over 9 years. At the population level, neither the COVID-19 pandemic nor the increased uptake of male childcare leave was associated with a measurable change in the AHT burden.
