Older people living in bad neighbourhoods could be at a higher risk of dementia, according to a new study.
Research, published in the Archives of General Psychiatry, considered the ε4 variant of the apolipoprotein (APOE) E gene, which is an important indicator of heightened risk and earlier onset of Alzheimer's disease.
It was found that those living in areas that "give rise to a heightened state of vigilance, alarm, or fear in residents that may lead to a biological stress response," performed worse in all seven cognitive tests.
"Our findings provide evidence that among persons with the APOE ε4 allele, cognitive performance in processing speed and executive function was significantly worse for persons residing in neighborhoods with higher levels of psychosocial hazards, with additional suggestive evidence for eye-hand coordination," said the authors.
Meanwhile, scientists have said that a new brain scan technique, being tested in NHS memory clinics, could be used to detect Alzheimer's disease and deliver results within just 24 hours.