Alzheimers

A study involving 105 people with Alzheimer's disease and 125 healthy older adults has compared cognitive function and brain shrinkage in those aged 60-75 and those aged 80+.

Sleep apnea linked to later dementia

A study involving 298 older women with sleep problems found that those who had disordered breathing (such as sleep apnea) were significantly more likely to develop dementia or mild cognitive impairment.

Functional impairment good indicator of mild cognitive impairment

I commonly refer to ApoE4 as the ‘Alzheimer’s gene’, because it is the main genetic risk factor, tripling the risk for getting Alzheimer's. But it is not the only risky gene.

A mammoth genetic study has identified four new genes linked to late-onset Alzheimer's disease. The new genes are involved in inflammatory processes, lipid metabolism, and the movement of molecules within cells, pointing to three new pathways that are critically related to the disease.

For the first time in 27 years, clinical diagnostic criteria for Alzheimer's disease dementia have been revised, and research guidelines updated. They mark a major change in how experts think about and study Alzheimer's disease.

The updated guidelines now cover three distinct stages of Alzheimer's disease:

A long-term study of older adults with similar levels of education has found that those with the thinnest cerebral cortex in specific brain regions were the most likely to develop dementia. Among those in whom these signature brain areas were the thinnest at the beginning of the study, 55% developed dementia over the next decade, compared with 20% of those with average cortical thickness and none of those in whom cortical thickness was above average. Those with the thinnest cortical areas also developed Alzheimer's significantly faster.

Some epidemiological studies have showed that people who smoke tend to have lower incidences of Parkinson's disease and Alzheimer's disease; this has been widely attributed to nicotine. However, nicotine's harmful effects make it a poor drug candidate.

Cotinine, a byproduct of nicotine metabolism, is nontoxic and longer lasting than nicotine.

A study following 837 people with MCI, of whom 414 (49.5%) had at least one vascular risk factor, has found that those with risk factors such as high blood pressure, diabetes, cerebrovascular disease and high cholesterol were twice as likely to develop Alzheimer's disease. Over five years, 52% of those with risk factors developed Alzheimer's, compared to 36% of those with no risk factors In total, 298 people (35.6%) developed Alzheimer's.

A review of 23 longitudinal studies of older adults (65+) has found that small amounts of alcohol were associated with lower incidence rates of overall dementia and Alzheimer dementia, but not of vascular dementia or age-related cognitive decline. A three-year German study involving 3,327 adults aged 75+ extends the evidence to the older-old.

A two-year study involving 53 older adults (60+) has found that those with a mother who had Alzheimer's disease had significantly more brain atrophy than those with a father or no parent with Alzheimer's disease. More specifically, they had twice as much gray matter shrinkage, and about one and a half times more whole brain shrinkage per year.

This atrophy was particularly concentrated in the precuneus and parahippocampal gyrus. Those with the APOE4 gene also had more atrophy in the frontal cortex than those who didn’t carry the ‘Alzheimer’s gene’.