New ‘risk-score’ method to predict dementia
A new study, published in the journal Lancet Neurology, has uncovered a method of identifying those likely to develop dementia later in life.
The study examined data from 1409 middle-aged Finnish individuals and then re-examined the sample 20 years later for signs of dementia. A score-based system was then developed from the results, allowing the chance of an individual suffering from dementia to be calculated. Those with a high score face up to a 16% chance of developing conditions, such as Alzheimer’s within the next 20 years. Factors considered in the ‘test’ include blood pressure, cholesterol level, body mass index, age, sex and level of education.
Lead researcher Miia Kivipelto is pleased with the results. “We wanted to develop a kind of practical tool to predict the risk of dementia in later life and we found there were indeed several modifiable risk factors.”
Evidence that individuals can act now to prevent future dementia cases and reduce the burden on healthcare systems is exciting news. Clive Ballard, director of research at the Alzheimer’s Society comments “New developments that encourage living a healthy lifestyle are an important step towards combating dementia”. He confirmed that the Alzheimer’s Society “recommend that people take regular exercise; eat healthily; make sure they get their blood pressure checked and take part in social activities”.
Whilst similar score-based systems are already available for conditions, such as diabetes and heart disease, this is the first time the risk factors for dementia have been identified. “It opens the prospect for the prevention of dementia,” states Alistair Burns, Professor of old-age psychiatry at the University of Manchester, UK.
The study has been called a ‘landmark paper’ by Jose Bertolote, coordinator of Mental and Brain Disorders at the WHO. “This is the first time that the synergistic effect of all these risk factors has been demonstrated.” However, he admits that “Even if you remove of all the risk factors, and control your blood pressure and cholesterol, and are not obese, there is no guarantee that you will not develop dementia.”
Further studies in different populations are needed to validate the results and it must be noted that common risk factors, such as smoking, alcohol consumption and diet, were not taken into consideration.
High birth-defect rates linked to epilepsy drugs
Research carried out by staff at the University of Florida (FL, USA) has revealed that one in five women taking the epileptic drug valproate during pregnancy experience birth defects and fetal death. Whilst the link between anti-epileptic drugs and birth defects has been known for many years, never before has the huge variety in risk between different drugs been demonstrated.
The study, published in Neurology, involved 333 pregnant women from the UK and USA who took one of four epilepsy drugs. The results revealed a 20.3% rate of birth defects/deaths for valproate, compared with 10.7% for phenytoin, 8.2% for carbamazepine and just 1% for lamotrigine. Defects witnessed included heart, brain and lung problems along with deformities of the skull and limbs.
Lead author, Kimford Meador, of the University of Florida and the American Academy of Neurology, advises “Although valproate will continue to be an important treatment option in women who aren’t able to use other epilepsy drugs, we’re advising valproate not to be used as the drug of first choice for women of child-bearing potential, and when used, its dosage should be limited if possible”.
Doctors are now advised to discuss the risks associated with choosing valproate with epileptic women who may wish to have children.
Whilst the results may be alarming, over 90% of women in the study gave birth to normal, healthy babies.
In addition, there may be other safer treatment options available to patients. Gholam Motamedi, Assistant Professor of Neurology at Georgetown University (WA, USA), notes that some newer anti-epilepsy drugs were not covered in the study.
Accelerated mental deterioration linked to high-fat, high-copper diet
A high intake of copper, in combination with a diet high in saturated and trans fats may lead to an accelerated rate of mental decline, according to a new study published in Archives of Neurology.
3718 local residents aged 65 years and older were studied by researchers at Rush University Medical Center, (IL, USA). The volunteers underwent thinking, learning and memory tests at the beginning of the study and then again after 3 and 6 years. The researchers interviewed the subjects on their diets, taking into consideration the consumption of vitamin supplements, to determine the amount of copper, iron and zinc consumed by individuals.
For individuals who consumed the highest amounts of saturated and trans fats, the link between copper intake and cognitive decline was noticeable. Those on high-fat diets and consuming an average 2.75 mg of copper a day had mental decline rates of almost 150% of those on high-fat diets but with moderate copper consumption (0.88 mg). The recommended daily allowance of copper is 0.9 mg.
Foods with the highest levels of copper include shellfish and organ meats, such as liver. However, there is no need to avoid such foods if a low saturated and trans fat diet is followed, as Martha Clare Morris, Associate Professor at the Institute for Healthy Aging at Rush University Medical Center explained. “We didn’t find copper was harmful at all in people who did not have this high-fat diet. But the combination of the two had a significant detrimental effect.”
Previous studies also support the link between high-fat diets and cognitive decline. Morris comments “We’re at a very early stage in this research, but this study gives us one more reason to limit the intake of saturated and trans facts”.
Mental decline was seen in all of the subjects as they aged, however, iron and zinc consumption had no effect on the rate of decline.
Timing of strokes linked to body clock
Strokes are more likely to occur in the morning or early evening than any other time, according to new research. Researchers at Iwate Medical University, Japan, analyzed data from 12,957 first-time stroke cases. The team searched for patterns in the wake–sleep cycle by dividing the day into 12 2-h intervals and using information on the timing of the stroke, when it was available.
The results showed that there are two periods of peak occurrence: between 6 and 8 a.m. and again between 6 and 8 p.m. Patterns within the three types of stroke studied vary. Whilst all three have two peaks, cerebral infarctions are more likely to occur in the morning, whilst subarachnoid and intracerebral hemorrhages are more likely to occur in the early evening.
Most cases of cerebral infarction, where blood flow to the brain is restricted, occur in the period immediately before waking in the morning. Low blood pressure is a risk factor for cerebral infarction and sleep lowers the blood pressure in the body, explained the authors.
Gray matter abnormalities found in autistic children
Researchers have discovered that children with autism spectrum disorder have structural brain abnormalities. Using magnetic resonance imaging (MRI), the team at the University Of Washington School Of Medicine in Seattle (WA, USA), analyzed transverse relaxation (T2) in children's brains. T2 relaxation is used to examine the progression of brain maturation by measuring how mobile water is in brain tissue. A total of 86 children aged 2–4 years were examined; 60 with autism; 16 with idiopathic developmental delay; and ten with typical brain development were used as controls.
The results revealed that children with autism have delayed development of gray matter, but normal white matter development. However, children with developmental delay had both prolonged gray and white matter T2, suggesting that there may be developmental abnormalities unique to autism. No relationship between intelligence quotient (IQ) and T2 results were discovered but Stephen Dager, lead author of the study, notes that it is difficult to accurately assess the IQ of very young children.
The results of the study, which are published in the August 22, 2006, issue of Neurology, contradict current theories. Dager comments “One of the more consistent brain findings associated with autism has been enlarged brain size. In contrast to current theories which suggest the enlarged brains are due to accelerated early growth tied to a more advanced stage of brain maturation, gray matter T2 relaxation findings were in the opposite direction. These results suggest that the mechanism or mechanisms responsible for larger brains in autism are different from more rapid growth.”