Other dementias: Brief summaries of research reports

General

March 2008

PET's targeted imaging may lead to earlier diagnosis of dementia

Use of PET imaging with the radiotracer fluorodeoxyglucose (FDG) has allowed researchers to classify different types of dementia (Alzheimer’s, frontotemporal dementia, and dementia with Lewy bodies) with very high rates of success (94%).
The study was reported in the March issue of the Journal of Nuclear Medicine.  Full reference
http://www.eurekalert.org/pub_releases/2008-03/sonm-pti030508.php

February 2008

Memory loss becoming less common in older Americans

A new nationally representative study involving 11,000 people shows a downward trend in the rate of cognitive impairment among people aged 70 and older, from 12.2% to 8.7% between 1993 and 2002. It’s speculated that factors behind this decline may be that today’s older people are much likelier to have had more formal education, higher economic status, and better care for risk factors such as high blood pressure, high cholesterol and smoking that can jeopardize their brains. In fact the data suggest that about 40% of the decrease in cognitive impairment over the decade was likely due to the increase in education levels and personal wealth between the two groups of seniors studied at the two time points. The trend is consistent with a dramatic decline in chronic disability among older Americans over the past two decades.
The study was published online ahead of print in Alzheimer’s and Dementia. Full reference
http://www.eurekalert.org/pub_releases/2008-02/uomh-mla021808.php

Vitamin E or C does not reduce risk of dementia or Alzheimer's

A five-year study involving nearly 3000 people has found that use of Vitamin C or E or both was not associated with a reduced risk of developing dementia or Alzheimer’s.
The study was published in the February issue of the Journal of the American Geriatrics Society. Full reference
http://www.eurekalert.org/pub_releases/2008-02/bpl-veo020408.php

PLMI factor in sleep disturbance for dementia patients

A study of 102 people diagnosed with both cognitive impairment and sleep disturbance (average nightly sleep of seven or less hours and daytime sleep of 30 minutes or longer) found that periodic leg movement disorder (a condition that causes people to jerk and kick their legs every 20 to 40 seconds during sleep) was predictive of reduced total sleep time in older adults with Alzheimer disease and related dementias. Given that sleep disturbance in persons with dementia is a highly prevalent and disabling symptom, and sedative-hypnotics are not recommended, this finding is important because it suggests treatment of periodic leg movements may be beneficial.
The study was published in the February 1 issue of SLEEP. Full reference
http://www.eurekalert.org/pub_releases/2008-02/aaos-ppt012808.php

January 2008

Mental and physical exercise delays dementia

A study using genetically engineered mice has found providing the mice with an enriched environment that enhanced their mental and physical stimulation improved performance on memory tests at an early stage of Huntington's disease, when memory impairment has begun. Specific molecular changes were also observed at the synapses in the hippocampus. Those without increased mental and physical activity showed decreased levels of specific proteins that are expressed at the synapse, but those exposed to stimulation didn’t. The finding offers hope for slowing the progression of the disease, as well as other dementias.
The report appeared online November 24 in the Neurobiology of Disease. Full reference
http://www.eurekalert.org/pub_releases/2008-01/ra-map012308.php

October 2007

National study of dementia prevalence

A study using data from 856 men and women who participated in the nationally representative Aging, Demographics and Memory Study estimates one in seven or 13.9% of the American population aged 71 and older, have some form of dementia. About 70% of those, or 9.7% of the population, have Alzheimer’s, and 17.4% of them have vascular dementia. As expected, the prevalence of dementia increased dramatically with age, from 5% of those aged 71 to 79 to 37.4% of those age 90 and older. With increasing age, Alzheimer’s disease accounted for progressively more of the dementia cases, so that in the 90+ age group, it comprised 79.5% of dementia cases, compared to 46.7% among those in their 70s. There was no difference between genders when corrected for education and age. Previous national estimates of dementia prevalence have been extrapolated from regional samples, and were generally significantly lower.
The findings were published in the November issue of Neuroepidemiology.   Full reference
Full text available at: http://content.karger.com/ProdukteDB/produkte.asp?Aktion=ShowPDF&ArtikelNr=109998&Ausgabe=233821&ProduktNr=224263&filename=109998.pdf http://www.eurekalert.org/pub_releases/2007-10/uom-oi7103007.php

November 2006

How whole-brain radiation might cause dementia

Whole-brain radiation is widely used to treat recurrent brain tumors as well as to prevent other cancers from spreading to the brain. About a half of patients later develop progressive memory problems. A new study has now identified changes in brain chemistry that may be responsible. Using middle-aged rats, researchers found changes in brain receptors for the neurotransmitter glutamate. The changes may impair synaptic communication.
The research was reported at the annual meeting of the Radiation Research Society in Philadelphia.
http://www.eurekalert.org/pub_releases/2006-11/wfub-ssp103006.htm

November 2005

More light on adult neurogenesis; implications for dementia and brain injuries

New research has demonstrated that adult mice produce multi-purpose, or progenitor, cells in the hippocampus, and indicates that the stem cells ultimately responsible for adult hippocampal neurogenesis actually reside outside the hippocampus, producing progenitor cells that migrate into the neurogenic zones and proliferate to produce new neurons and glia. The finding may help in the development of repair mechanisms for people suffering from dementia and acquired brain injury.
The study appeared as the cover story in November 23 issue of the Journal of Neuroscience. Full reference
http://www.eurekalert.org/pub_releases/2005-11/ra-nrt112305.htm

July 2005

Study links adolescent IQ/activity levels with risk of dementia

An analysis of high school records and yearbooks from the mid-1940s, and interviews with some 400 of these graduates, now in their 70s, and their family members, has found that those who were more active in high school and who had higher IQ scores, were less likely to have mild memory and thinking problems and dementia as older adults.
The results were published in the July 2005 issue of the Journal of the American Geriatrics Society. Full reference
http://www.eurekalert.org/pub_releases/2005-07/cwru-sla070105.htm

September 2004

Walking may protect elderly from dementia

A study of more than 2,200 Japanese-American men between the ages of 71 and 93 has found that elderly men who are sedentary or walk less than a quarter of a mile per day are nearly twice as likely to develop dementia and Alzheimer's disease compared to men who walk more than two miles per day. Those who walked less than a mile (and more than quarter of a mile) a day also showed a significantly greater risk of dementia than those walking more than two miles a day.
The study was published in the Sept. 22 issue of the Journal of the American Medical Association. Full reference
http://www.eurekalert.org/pub_releases/2004-09/uovh-wmp091504.htm

Drinking too much alcohol, and not enough, increases risk of cognitive impairment

In Finland, researchers re-examined 1018 participants from a study of 1464 men and women aged 65-79 studied in 1972 or 1977. They found that participants who drank no alcohol in midlife as well as those who drank alcohol frequently were twice as likely to have mild cognitive impairment in old age compared to those who drank alcohol infrequently. The effect of alcohol was however modified by the presence of the apolipoprotein e4 allele (implicated in dementia risk). People who were carriers of the apolipoprotein e4 allele had an increased risk of dementia with increasing alcohol consumption, with carriers of the gene significantly reducing their risk by never drinking.
The study was reported in the September 4 issue of the British Medical Journal. Full reference

June 2004

Estrogen-alone hormone therapy could increase risk of dementia in older women

A new report from the Women's Health Initiative Memory Study suggests that older women using estrogen-alone hormone therapy could be at a slightly greater risk of developing dementia, including Alzheimer's disease (AD), than women who do not use any menopausal hormone therapy. Among 10,000 women using conjugated equine estrogens, 37 could be expected to develop dementia, compared to 25 in 10,000 women using the placebo. Previous reports from the Study found a greater risk with hormone therapy involving both estrogen plus progestin: among 10,000 women over age 65 using estrogen plus progestin there might be 45 cases of dementia compared to 22 cases in 10,000 older women on placebo.
It was also reported that beginning estrogen-alone hormone therapy after age 65 can have a small negative effect on overall cognitive abilities and that this negative effect may be greater in women with existing cognitive problems.
These findings appeared in the June 23/30 issue of the Journal of the American Medical Association. Full reference 2
http://www.eurekalert.org/pub_releases/2004-06/nioa-eht062204.htm
http://www.eurekalert.org/pub_releases/2004-06/wfub-etd061704.htm

June 2003

More evidence that mental exercise helps prevent or postpone dementia

Another study provides support for the idea that mentally demanding activities can help stave off dementia. The study involved 469 people aged 75 and older. Over the course of the study, dementia developed in 124 of the participants (Alzheimer's disease in 61,vascular dementia in 30, mixed dementia in 25, and other types of dementia in 8). Those who participated at least twice weekly in reading, playing games (chess, checkers, backgammon or cards), playing musical instruments, and dancing were significantly less likely to develop dementia. Although the evidence on crossword puzzles was not quite statistically significant, those who did crossword puzzles four days a week had a much lower risk of dementia than those who did one puzzle a week. Most physical activities, like group exercise or team games, had no significant impact. The only exception - ballroom dancing - possibly occurred because of the mental demands of remembering dance steps, responding to music and coordinating with a partner. Although the study was careful to include only those who showed no signs of dementia at the start, it cannot be ruled out that people in pre-clinical stages of dementia may be less likely to participate in mentally demanding activities.
The study was published in the June 19 issue of the New England Journal of Medicine. Full reference
http://www.nytimes.com/2003/06/24/opinion/24TUE4.html?th

Return to top

Vascular dementia

December 2007

Walking and moderate exercise help prevent dementia

A four-year study involving 749 older adults has found that the top one-third of participants who exerted the most energy in moderate activities such as walking were significantly less likely to develop vascular dementia than those people in the bottom one-third of the group. Contrary to some reports, no such association was found with Alzheimer’s disease.
The study was published in the December 19 issue of Neurology.  Full reference
http://www.eurekalert.org/pub_releases/2007-12/aaon-wam121107.php

June 2003

More evidence that mental exercise helps prevent or postpone dementia

Another study provides support for the idea that mentally demanding activities can help stave off dementia. The study involved 469 people aged 75 and older. Over the course of the study, dementia developed in 124 of the participants (Alzheimer's disease in 61,vascular dementia in 30, mixed dementia in 25, and other types of dementia in 8). Those who participated at least twice weekly in reading, playing games (chess, checkers, backgammon or cards), playing musical instruments, and dancing were significantly less likely to develop dementia. Although the evidence on crossword puzzles was not quite statistically significant, those who did crossword puzzles four days a week had a much lower risk of dementia than those who did one puzzle a week. Most physical activities, like group exercise or team games, had no significant impact. The only exception - ballroom dancing - possibly occurred because of the mental demands of remembering dance steps, responding to music and coordinating with a partner. Although the study was careful to include only those who showed no signs of dementia at the start, it cannot be ruled out that people in pre-clinical stages of dementia may be less likely to participate in mentally demanding activities.
The study was published in the June 19 issue of the New England Journal of Medicine. Full reference
http://www.nytimes.com/2003/06/24/opinion/24TUE4.html?th

Chinese herb effective in treating vascular dementia

The herb gastrodine has been used in China for centuries to treat disorders such as dizziness, headache and even ischemic stroke. Now a 12-week, randomized, double-blind trial comparing gastrodine with Duxilâ (a drug used to treat stroke patients in China) has been done in Beijing Dongzhimen Hospital. The trial involved 120 stroke patients who were diagnosed with mild to moderate vascular dementia. Both treatment groups showed similar improvement in memory, orientation, calculation, and language (as measured by the MMSE). The gastrodine group also showed a significant difference in the Blessed Behavioral Scale (BBS) score - including behavior, activities of daily living, and also suffered fewer side effects. Researchers say combined results showed the gastrodine group improvement was 51.43 percent, with 16 of the 70 cases showing much improvement, 20 cases with some improvement, and 34 cases with no change. The improvement rate for patients treated with Duxilâ was 52 percent, with seven of the 50 cases showing much improvement, 19 cases with some improvement, and 24 cases with no change.
The research was presented at the American Heart Association's Second Asia Pacific Scientific Forum in Honolulu on June 10.
http://www.eurekalert.org/pub_releases/2003-06/aha-nhd052303.htm

May 2003

For women over 65, Combined Hormone Therapy increases risk of dementia

Much to the researchers’ surprise and disappointment, a four-year experiment involving 4,532 women at 39 medical centers, has found that combined hormone therapy (involving both estrogen and progestin) doubles the risk of Alzheimer's disease and other types of dementia in women who began the treatment at age 65 or older, although the risk is still small : for every 10,000 women 65 and older who take hormones, 23 of the predicted 45 cases of dementia a year, will be attributable to the hormones. The study also found that the combined hormone therapy produced no improvement in general cognitive function, and in fact had adverse effects on cognition among some women. This supports an earlier study suggesting that, while estrogen is helpful to cognitive function in postmenopausal women, the benefits can be cancelled out by progestin / progesterone. The study also confirmed previous research showing that the combination therapy increased the risk of stroke - previous research has indicated that risk factors for stroke are also risk factors for cognitive decline.
The study was published in the May 28 issue of the Journal of the American Medical Association. Full reference 2 3
http://www.eurekalert.org/pub_releases/2003-05/wfub-chr052203.htm

Treatment to lower blood pressure reduces risk of cognitive decline in stroke patients

High blood pressure and stroke are associated with increased risks of dementia and cognitive impairment. In a study aimed to determine whether blood pressure lowering would reduce the risks of dementia and cognitive decline among individuals with cerebrovascular disease, 6105 people with prior stroke or transient ischemic attack were given either active treatment (perindopril for all participants and indapamide for those with neither an indication for nor a contraindicationto a diuretic) or matching placebo(s). Over some 4 years, dementia was found in 6.3% of those given active treatment and 7.1% of those in the placebo group. Cognitive decline occurred in 9.1% of the actively treated group and 11.0%of the placebo group. The researchers concluded that blood pressure lowering with perindopril and indapamide therapy was helpful for those with cerebrovascular disease, in terms of reduced risks of dementia and cognitive decline.
The study was published in the May 12 issue of the Archives of Internal Medicine. Full reference
http://archinte.ama-assn.org/cgi/content/abstract/163/9/1069

February 2003

Pilot study finds ginseng may improve memory in stroke dementia patients

Following mouse studies showing that ginseng increased the activities of the brain chemicals acetylcholine and choline acetyltransferase, a pilot study of 40 patients (average age 67) with mild to moderate vascular dementia was undertaken by Chinese researchers. 25 patients were randomly selected to receive ginseng extract, while 15 received the drug Duxil® (used to improve memory in elderly dementia patients). Overall, researchers found that patients who took the ginseng compound significantly improved their average memory function after 12 weeks. More research (larger samples, placebo-controls) is needed before this finding can be confirmed.
The study was reported at the American Stroke Association's 28th International Stroke Conference on February 14 in Phoenix.
http://www.eurekalert.org/pub_releases/2003-02/aha-gmi020403.htm

Return to top

Frontotemporal dementia

July 2007

New gene mutation identified in frontotemporal dementia

A family in southern Italy has enabled researchers to identify a gene mutation that increases the chances of frontotemporal dementia. The gene is located on chromosome 17 and is named progranulin. The mutation leads to a loss of progranulin, a protein growth factor that helps brain cells survive. Production of too much progranulin has been associated with cancer. The genetic form of the disease is rare, however.
The study was published in the July 10 issue of Neurology. Full reference
http://www.eurekalert.org/pub_releases/2007-07/aaon-ngm062907.php

November 2003

Population level of frontotemporal dementia

A large-scale epidemiological study in the Netherlands has found an incidence of frontotemporal dementia that equates to a population level of 1.1 per 100,000. The prevalence was highest among those ages 60 to 69, at 9.4 per 100,000. The prevalence among people ages 45 to 64 was estimated to be 6.7 per 100,000. Symptoms began after age 65 in 22% of patients. Whites accounted for 99% of all cases despite an ample nonwhite population. A family history of dementia was present in 43% of patients.
The study was reported in the September issue of Brain. Full reference

Return to top

HIV-associated dementia

May 2007

Green tea extract protects against HIV-associated dementia

A compound derived from green tea greatly reduced the neurotoxicity of proteins secreted by the human immunodeficiency virus, suggesting a new approach to the prevention and treatment of HIV-associated dementia.
Brian Giunta reported the findings May 1 at Experimental Biology 2007 in Washington, DC.
http://www.eurekalert.org/pub_releases/2007-05/uosf-gte042707.htm

Return to top