Patients over the age of 65 who begin taking benzodiazepine (a popular drug used to treat anxiety and insomnia) are at an approximately 50% increased risk of developing dementia within 15 years compared to never-users, a study published recently on the British Medical Journal website suggests.

The authors say that "considering the extent to which benzodiazepines are prescribed and the number of potential adverse effects indiscriminate widespread use should be cautioned against."

Benzodiazepine is a widely prescribed drug for the over 65s in many countries: 30% of this age group in France, 20% in Canada and Spain, 15% in Australia. Although less widespread in the UK and US it is still very widely used and many individuals take this drug for years despite guidelines suggesting it should be limited to a few weeks. Previous studies have found an increased risk of dementia, but others have been non-conclusive.

Researchers from France therefore carried out a study on 1063 men and women (average age 78) in France who were all free of dementia at the start. The study started in 1987 and follow-up was 20 years. The researchers used the first 5 years to identifying the factors leading to benzodiazepine initiation and evaluated then the association between new use of this drug and the development of dementia. They also assessed the association between further benzodiazepine initiation during the follow-up period and risk of subsequent dementia. Rates were adjusted for many factors potentially affecting dementia, such as age, gender, educational level, marital status, wine consumption, diabetes, high blood pressure, cognitive decline, and depressive symptoms.

95 out of the 1063 patients started taking benzodiazepine during the study. 253 (23.8%) cases of dementia were confirmed, 30 in benzodiazepine users and 223 in non-users. New initiation of the drug was associated with shorter dementia-free survival.

In absolute numbers, the chance of dementia occurring was 4.8 per 100 person years in the exposed group compared to 3.2 per 100 person years in the non-exposed group. A "person year" is a statistical measure representing one person at risk of development of a disease during a period of one year.

The authors say that although benzodiazepine remains useful for treating anxiety and insomnia, there is increasing evidence that its use may induce adverse outcomes in the elderly such as serious falls and fall-related fractures and this study may add dementia to the list. They say that their data add to the accumulating evidence that the use of benzodiazepines is associated with increased risk of dementia and, if true, that this "would constitute a substantial public health concern." Therefore, taken the evidence of potential adverse effects into account, physicians should assess expected benefits, limit prescriptions to a few weeks, and uncontrolled use should be cautioned against. They conclude that further research should "explore whether use of benzodiazepine in those under 65 is also associated with increased risk of dementia and that mechanisms need to be explored explaining the association"

Can you bite into an apple? If so, you are more likely to maintain mental abilities, according to new research from Karolinska Institutet in Sweden.

The population is aging, and the older we become the more likely it is that we risk deterioration of our cognitive functions, such as memory, decision-making and problem solving. Research indicates several possible contributors to these changes, with several studies demonstrating an association between not having teeth and loss of cognitive function and a higher risk of dementia.

One reason for this could be that few or no teeth makes chewing difficult, which leads to a reduction in the blood flow to the brain. However, to date there has been no direct investigation into the significance of chewing ability in a national representative sample of elderly people.  

Now a team comprised of researchers from the Department of Dental Medicine and the Aging Research Center (ARC) at Karolinska Institutet and from Karlstad University in Sweden have looked at tooth loss, chewing ability and cognitive function in a random nationwide sample of 557 people aged 77 or older. They found that those who had difficulty chewing hard food such as apples had a significantly higher risk of developing cognitive impairments. This correlation remained even when controlling for sex, age, education and mental health problems, variables that are often reported to impact on cognition. Whether chewing ability was sustained with natural teeth or dentures also had no bearing on the effect.

The results are published in the Journal of the American Geriatrics Society (JAGS). The study was financed with grants from several funds, including the Swedish Council for Working Life and Social Research and the Swedish Research Council.

Journal Reference:

1. Duangjai Lexomboon, Mats Trulsson, Inger Wårdh & Marti G. Parker. Chewing Ability and Tooth Loss: Association with Cognitive Impairment in an Elderly Population Study. Journal of the American Geriatrics Society, 2012

People 70 and older who eat food high in carbohydrates have nearly four times the risk of developing mild cognitive impairment, and the danger also rises with a diet heavy in sugar, Mayo Clinic researchers have found. Those who consume a lot of protein and fat relative to carbohydrates are less likely to become cognitively impaired, the study found. The findings are published in the Journal of Alzheimer's Disease.

The research highlights the importance of a well-rounded diet, says lead author Rosebud Roberts, M.B., Ch.B., a Mayo Clinic epidemiologist.

"We think it's important that you eat a healthy balance of protein, carbohydrates and fat, because each of these nutrients has an important role in the body," Dr. Roberts says.

Researchers tracked 1,230 people ages 70 to 89 who provided information on what they ate during the previous year. At that time, their cognitive function was evaluated by an expert panel of physicians, nurses and neuropsychologists. Of those participants, only the roughly 940 who showed no signs of cognitive impairment were asked to return for follow-up evaluations of their cognitive function. About four years into the study, 200 of those 940 were beginning to show mild cognitive impairment, problems with memory, language, thinking and judgment that are greater than normal age-related changes.

Those who reported the highest carbohydrate intake at the beginning of the study were 1.9 times likelier to develop mild cognitive impairment than those with the lowest intake of carbohydrates. Participants with the highest sugar intake were 1.5 times likelier to experience mild cognitive impairment than those with the lowest levels.

But those whose diets were highest in fat — compared to the lowest — were 42 percent less likely to face cognitive impairment, and those who had the highest intake of protein had a reduced risk of 21 percent.

When total fat and protein intake were taken into account, people with the highest carbohydrate intake were 3.6 times likelier to develop mild cognitive impairment.

"A high carbohydrate intake could be bad for you because carbohydrates impact your glucose and insulin metabolism," Dr. Roberts says. "Sugar fuels the brain — so moderate intake is good. However, high levels of sugar may actually prevent the brain from using the sugar — similar to what we see with type 2 diabetes."

 People whose blood sugar is on the high end of the normal range may be at greater risk of brain shrinkage that occurs with aging and diseases such as dementia, according to new research published in the September 4, 2012, print issue of Neurology®, the medical journal of the American Academy of Neurology.

"Numerous studies have shown a link between type 2 diabetes and brain shrinkage and dementia, but we haven't known much about whether people with blood sugar on the high end of normal experience these same effects," said study author Nicolas Cherbuin, PhD, with Australian National University in Canberra.

The study involved 249 people age 60 to 64 who had blood sugar in the normal range as defined by the World Health Organization. The participants had brain scans at the start of the study and again an average of four years later.

Those with higher fasting blood sugar levels within the normal range and below 6.1 mmol/l (or 110 mg/dL) were more likely to have a loss of brain volume in the areas of the hippocampus and the amygdala, areas that are involved in memory and cognitive skills, than those with lower blood sugar levels. A fasting blood sugar level of 10.0 mmol/l (180 mg/dL) or higher was defined as diabetes and a level of 6.1 mmol/l (110 mg/dL) was considered impaired, or prediabetes.

After controlling for age, high blood pressure, smoking, alcohol use and other factors, the researchers found that blood sugar on the high end of normal accounted for six to 10 percent of the brain shrinkage.

"These findings suggest that even for people who do not have diabetes, blood sugar levels could have an impact on brain health," Cherbuin said. "More research is needed, but these findings may lead us to re-evaluate the concept of normal blood sugar levels and the definition of diabetes."

The study was supported by the National Health and Medical Research Council Australia and the Australian Rotary Health Research Fund.

Delirium is widespread among older people but often goes ignored and untreated, according to new research by US and UK researchers including the University of East Anglia (UEA).

Published in the September issue of the Journal of Hospital Medicine, the findings show that delirium — or acute confusion — is common among older adults in hospitals and nursing homes. It has a negative impact on cognition and independence, significantly increases the risk of developing dementia, and triples the likelihood of death. Yet this common, acute condition is frequently either undiagnosed or accepted as inevitable.

Led by the Regenstrief Institute and Indiana University, the research team reviewed 45 years of research encompassing 585 studies. They found that one in three cases of delirium were preventable and are calling for delirium to be identified and treated early to prevent poor long-term prognosis.

"As a geriatric psychiatrist I have seen that around 50 per cent or people with dementia in hospital develop delirium," said co-author Dr Chris Fox, of Norwich Medical School at the University of East Anglia.

"This is because in addition to having dementia, they have multiple risk factors that can predispose and precipitate delirium — including serious illnesses and pre-existing cognitive impairment. In addition, hospital staff commonly label the signs as dementia related and do not pick up the delirium."

"We need to develop better mechanisms for diagnosing delirium so that prompt treatment regimes can be initiated."

In general patient groups, more than 60 per cent of delirium cases are not recognised or treated, and significant numbers of elderly patients leave hospital with ongoing delirium which has been missed.

The authors, led by Dr Babar Khan of the Regenstrief Institute and Indiana University School of Medicine, said that delirium could be prevented by eliminating restraints, treating depression, ensuring that patients have access to glasses and hearing aids, and prescribing classes of antipsychotics that do not negatively affect the aging brain. They also noted the need for a more sensitive screening tool for delirium, especially when administered by a non-expert.

"Delirium is extremely common among older adults in intensive care units and is not uncommon in other hospital units and in nursing homes, but too often it is ignored or accepted as inevitable," said Dr Khan. "Delirium significantly increases risk of developing dementia and triples likelihood of death. It cannot be ignored."

Co-author Dr Malaz Boustani, of the Regenstrief Institute, Indiana University School of Medicine and Wishard Healthy Aging Brain Center, said: "Having delirium prolongs the length of a hospital stay, increases the risk of post-hospitalization transfer to a nursing home, increases the risk of death and may lead to permanent brain damage."

'Delirium in Hospitalized Patients: Implications of Current Evidence on Clinical Practice and Future Avenues for Research — A Systematic Evidence Review' by Mohammed Zawahiri (Regenstrief Institute and IU Center for Aging Research), Noll L. Campbell (Regenstrief Institute, Purdue University and Wishard Health Services), Chris Fox (University of East Anglia), Eric Weinstein (Tri-State Pulmonary Associates), Arif Nazir (IU School of Medicine), Mark Farber (IU School of Medicine), John Buckley (IU School of Medicine), and Alasdair MacLullich (University of Edinburgh) is published online by the Journal of Hospital Medicine on September 18.

The study was supported by the National Institute on Aging and the National Institute of Mental Health.

Treatment with growth hormone-releasing hormone appears to be associated with favorable cognitive effects among both adults with mild cognitive impairment and healthy older adults, according to a randomized clinical trial published Online First by Archives of Neurology, a JAMA Network publication.

Migraines currently affect about 20 percent of the female population, and while these headaches are common, there are many unanswered questions surrounding this complex disease. Previous studies have linked this disorder to an increased risk of stroke and structural brain lesions, but it has remained unclear whether migraines had other negative consequences such as dementia or cognitive decline. According to new research from Brigham and Women's Hospital (BWH), migraines are not associated with cognitive decline.