Related Experiment Video
Updated: Jul 16, 2026

Highlighting and Reducing the Impact of Negative Aging Stereotypes During Older Adults' Cognitive Testing
Published on: January 24, 2020
Heterogeneous associations of cumulative heat exposure with cognitive decline among older Japanese adults
Hiroyuki Hikichi1, Kai Chen2,3, Nobutoshi Nawa4,5
1Department of Public Health, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan.
Introduction:
We investigated heterogeneity in the association between cumulative heat exposure and cognitive decline among older Japanese adults.
Methods:
We analyzed 33,877 adults aged ≥ 65 years from a nationwide cohort (2010-2023) linked with long-term care insurance data. Cumulative heat exposure was indexed using population-weighted wet-bulb globe temperature. Generalized random forests estimated the average and conditional treatment effects. Heterogeneity was decomposed using permutation importance, excess CATE analysis, and UpSet plot analyses.
Results:
During a 12-year follow-up, 25.3% developed cognitive decline. Heat exposure increased incidence by 12.17 cases per 1000 person-years (95% confidence interval [CI]: 2.54-21.62). Vulnerability profiles differed by age: among adults aged 65-74 years, multidimensional social and health constraints predominated; among those aged ≥ 75 years, functional decline and relational depletion dominated.
Discussion:
Age-specific vulnerability profiles provide a foundation for precision public health: multidomain interventions for adults aged 65-74 years and proactive social outreach for those aged ≥ 75 years.
Related Concept Videos
Cognitive Development During Adulthood
The Effect of Aging on Tissues
Aging
Cellular Clock Theory
The cellular clock theory posits that the human lifespan is closely tied to the finite capacity of cells to divide, a phenomenon governed by telomeres, which are protective caps at the ends of...
Bias in Epidemiological Studies
Responses to Heat and Cold Stress
Environmental Influences on Intelligence