The National Police Agency said Thursday that 4.1 percent of police officers in Iwate, Miyagi and Fukushima prefectures may be suffering posttraumatic stress disorder stemming from last year's quake, tsunami and nuclear crisis.
None of the officers has been officially diagnosed as having PTSD. Even so, the NPA plans to take long-term preventive measures after a survey conducted in January and February on 9,847 officers indicated some could develop delayed symptoms.
A similar survey of 7,750 police officers in the three prefectures between April and May last year showed that 587, or 7.6 percent, were at risked of developing PTSD.
"Stress on police officers has mitigated as time has gone by, and counseling by psychotherapists might have achieved some results," an NPA official said, comparing the sets of data.
The latest survey comprised 32 questions, including whether respondents sleep badly and wake up in the middle of the night, with the option of replying "yes," "no" or "sometimes."
The NPA said those who have faced changes in their working environment, have had less communications with coworkers, or who themselves or their family members have been directly hit by the disaster are mostly likely to develop PTSD.
The Defense Ministry said that of the 58,000 Ground Self-Defense Force members involved in disaster-relief operations, 3.3 percent were found one month after completing their missions to be at risk of developing PTSD.