Higher Risks for Alzheimer Disease Associated With Living in Poorer Areas

 According to a study in Neurology, individuals living in areas with higher poverty levels and fewer opportunities had more atrophy on brain scans and showed faster decline on cognitive tests, both associated with risk of Alzheimer disease (AD). In this longitudinal study, individuals with a mean age of 59 were followed for 10 years.

At the start of the study, there was no difference in brain volume between individuals living in disadvantaged neighborhoods and those in other neighborhoods. By the end of the study, there was atrophy in brain areas associated with dementia in people in the most disadvantaged neighborhoods but not in those living in other neighborhoods. A higher rate of decline on neurocognitive tests that measure risk of AD was also seen in those living in poorer neighborhoods.
  
“Worldwide, dementia is a major cause of illness and a devastating diagnosis,” said study author Amy J. H. Kind MD, PhD, of the University of Wisconsin School of Medicine and Public Health in Madison. “There are currently no treatments to cure the disease, so identifying possible modifiable risk factors is important. Compelling evidence exists that the social, economic, cultural and physical conditions in which humans live may affect health. We wanted to determine if these neighborhood conditions increase the risk for the neurodegeneration and cognitive decline associated with the earliest stages of AD and dementia.” 
  
For the study, 601 individuals were identified from 2 larger studies of Wisconsin residents. Participants had an average age of 59 with no thinking or memory problems at the start of the study. Of the participants, 69% had a family history of dementia. Of all participants, 19 lived in the 20% most disadvantaged neighborhoods and 582 lived in the 80% of all other neighborhoods.
  
Participants had an initial MRI brain scan and then additional scans every 3 to 5 years. Each scan measured brain volume in areas of the brain linked to the development of AD. Participants also took thinking and memory tests every 2 years, including tests that measured processing speed, mental flexibility and executive function. 
    
“Our findings suggest that increased vigilance by healthcare providers for early signs of dementia may be particularly important in this vulnerable population,” said Kind. “Some possible causes of these brain changes may include air pollution, lack of access to healthy food and healthcare and stressful life events. Further research into possible social and biologic pathways may help physicians, researchers and policymakers identify effective avenues for prevention and intervention in AD and related dementia.”