Skip to main content

Alzheimer's & Dementia

Latest News

  • Very large study finds 5 new genes linked to increased Alzheimer's risk.
  • A rare gene variant that protects APOE4 gene carriers from getting Alzheimer's has been identified.
  • Two large surveys found that verbal recall score was significantly affected by TOMM40 genotype. TOMM40 is adjacent to APOE on their chromosome.
  • A study found that TOMM40's effect on Alzheimer's depends on parental history.
  • Data from three very large studies has produced a tool for assessing an individual's genetic risk for developing Alzheimer's, based on 31 genetic markers.
  • A small study found that, of the top 9 genes that affect Alzheimer's risk, excluding the APOE gene, only 2 affect brain atrophy.
  • A new gene variant that is associated with greater amyloid plaque than APOE4 has been identified.

Five new risk genes for Alzheimer's disease

Genetic data from more than 94,000 individuals has revealed five new risk genes for Alzheimer's disease, and confirmed 20 known others. The new genes are: IQCK, ACE, ADAM10, ADAMTS1 and WWOX.

  • A very large Korean study found older adults with chronic periodontitis had a 6% higher risk for dementia.
  • Two animal studies found that the bacteria involved in gum disease increases amyloid-beta, brain inflammation, and neuron death.

Periodontitis raises dementia risk

  • A very large study found that an unhealthy lifestyle and high genetic risk were independently associated with higher dementia risk, and a healthy lifestyle reduced the risk for those at high genetic risk.

Data from 196,383 older adults (60+; mean age 64) in the UK Biobank found that a healthy lifestyle was associated with lower dementia risk regardless of genes.

Both an unhealthy lifestyle and high genetic risk were associated with higher dementia risk.

Data from the population-based Finnish Cardiovascular Risk Factors, Aging and Incidence of Dementia (CAIDE) study has revealed that healthy dietary choices in midlife may prevent dementia in later years. Out of 2,000 participants, 1,449 took part in the follow-up.

A post-mortem study of five Alzheimer's and five control brains has revealed the presence of iron-containing microglia in the subiculum of the Alzheimer's brains only. The subiculum lies within the hippocampus, a vital memory region affected early in Alzheimer's.

  • It seems clear now that a substantial decline in sense of smell is a very early sign of developing MCI and Alzheimer's.
  • Several tests have been developed to assess this.
  • It should always be remembered that there is substantial difference between individuals in their 'natural' sense of smell, and this needs to be taken into account in any test.

In the past few months, several studies have come out showing the value of three different tests of people's sense of smell for improving the accuracy of MCI and Alzheimer's diagnosis, or pointing to increased risk.

  • A short exercise program improved cognition and brain blood flow in older adults with mild cognitive impairment.

A small study has found that a 12-week exercise program significantly improved cognition in both older adults with MCI and those who were cognitively healthy, but that effect on blood flow in the brain was different in these two groups.

  • A study found an association in healthy older adults between higher amyloid beta levels and worsening anxiety.

Data from the Harvard Aging Brain Study found that higher amyloid beta levels were associated with increasing anxiety symptoms in cognitively normal older adults. The results suggest that worsening anxious-depressive symptoms may be an early predictor of elevated amyloid beta levels.

  • A rat brain cell study provides evidence that alcohol may increase Alzheimer's risk by impeding the removal of amyloid-beta protein.
  • A very large French study found that 38% of early-onset dementia cases were directly alcohol-related and 18% had an additional diagnosis of alcohol use disorders.

How alcohol increases Alzheimer's risk

A French study involving 36 healthy older adults (60-80), prescreened for amyloid deposits in the brain to exclude people who might have preclinical Alzheimer’s disease, has found a linear increase in gray matter volume in proportion to the number of years of education (7-20 years).