Childhood experiences can have an outsized impact on people with dementia. A new study has found that people who have weathered three or more adverse childhood experiences have an increased risk for developing dementia, finds a new study from Japan.

Researchers surveyed more than 150,000 Japanese adults ages 65 and older about specific childhood experiences before the age of 18. These included parental death, parental divorce, parental mental illness, family violence, physical abuse, psychological neglect and psychological abuse. Participants’ cognitive status was measured three years after the survey.

Only 2% of participants reported that they had suffered three of these adverse events. This group was at greater risk of developing dementia compared with those who reported no adverse childhood experiences, reported Katsunori Kondo, M.D., Ph.D., and colleagues. 

The results held after adjustment for age, sex, childhood economic hardship, nutritional environment and education, wrote Kondo, from the National Center for Geriatrics and Gerontology, Aichi.

At times, it may be these past experiences and not dementia itself that cause distress and behavioral problems in some elders with dementia, according to the researchers behind an earlier study. In some cases, these events can lead to delayed post-traumatic stress disorder, they said.

If clinicians can pinpoint the unique origins of an elder’s distress, this can enable them to better plan treatment and improve outcomes for the patient, they concluded.

The study was published in JAMA Network Open.