In developed nations, human life expectancy has increased steadily for over a century. One of the few negative consequences of this trend has been a marked increase in the prevalence of Alzheimer’s disease, an age-related untreatable condition that has driven enormous health spending on a national scale and wrecked the finances of millions of families in the US alone. Now, with the oldest Baby Boomers just reaching age 65, Alzheimer’s disease seems destined to become a true national health crisis.

Two of the most vexing problems with this nasty disease are determining who has it and diagnosing it early enough (so scientists can understand how it progresses and someday, intervene to either cure it or halt its progression).

With current technology, the only way to accurately diagnose Alzheimer’s disease is at autopsy. Special tests of the deceased’s brain reveal the sine qua non of Alzheimer’s disease: amyloid plaques.

But last week, 2 studies appearing in JAMA provided rays of hope in this otherwise dismal state of affairs. We review them both below:

Brain Scan Detects Plaques
In the first study, scientists injected a radioactive dye known as Flobetapir F 18 into the blood of elderly volunteers, and then used PET scans to image their brains.  Florbetapir F 18 had been designed by Christopher Clark and colleagues at Avid Radiopharmaceuticals to bind to amyloid proteins—which are the main constituents of amyloid plaques—and thus make them visible in vivo using the PET scan.

The PET scans correctly identified amyloid plaques in 97% of the volunteers that actually had them, as proven at autopsy. In addition, PET scans performed after the dye had been injected into young, healthy volunteers revealed no plaques.

Scientists believe the Florbetapir F 18 PET scans could be helpful as a means to exclude the diagnosis of Alzheimer’s. If no plaques are found in a patient with symptoms of dementia, physicians would be compelled to consider other causes of the symptom complex. The PET scans could also potentially be used to test drugs designed to remove amyloid from the brain.

A Blood Test for Alzheimer’s
The second study showed that blood levels of amyloid protein, as detected by a new blood test, were correlated with memory problems.

The study was directed by Kristine Yaffe at UCSF. Her group recruited 997 elderly volunteers and followed them with memory tests and amyloid blood tests for 9 years. (more…)

Responding to criticism from scientists and the FDA, Walgreens has postponed plans to market a personal genetic test kit made by Pathway Genomics

“We’ve elected not to move forward with offering the Pathway product to our customers until we have further clarity on this matter,” a Walgreens statement said.

The Pathway Genomics kit uses saliva samples to assess one’s risk of contracting in excess of 70 diseases including lung cancer, hypertension and heart disease.

The kits cost $20. They include a plastic container, handy instructions and a postage-paid envelope to ship the specimen to a San Diego-based laboratory. Testing costs an additional $79 to $249.

The state-of-the-art in genomic science these days is that it’s easy and inexpensive to obtain genetic markers for a host of diseases, but there is insufficient data to give much credence to the findings…at least for diseases like cancer, diabetes and heart disease which are thought to be influenced by hundreds of different genes.

“Many of these markers are not understood, even what genes they are affecting right now,” Kenneth Offit, the chief of clinical genetics at Memorial Sloan-Kettering Cancer Center in New York told CNN. “It’s a very, very early stage in this level of genomic research.”

For its part, the FDA said, “Pathway Genomics has moved outside of the currently sanctioned boundaries for lab-developed tests by marketing (its) product in a retail store. These kits have not been proven safe, effective or accurate. Patients could be making medical decisions based on data from a test that hasn’t been validated by the FDA.”

Of note, Pathway Genomics has sold these kits online for the last 8 months. In fact, more than 30 companies offer personal genetic tests on line.

A recent study in Pediatrics suggests that about 1% of US children have autism or a related disorder. That’s nearly 50% higher than previous estimates.

To determine the prevalence of the condition among US children aged 3 to 17 years, Michael Kogan and colleagues at the Health Resources and Services Administration and the CDC queried data from the 2007 National Survey of Children’s Health, which involved outbound calls to more than 78,000 parents.

In the Survey, parents were asked whether a health care provider had ever told them their child had autism, Asperger’s disorder, or pervasive developmental disorder, which are the 3 behavioral conditions that comprise Autism spectrum disorder, or ASD.

Parents who said yes were then asked whether their child had the condition at the time of the call.

The scientists found that 673,000 children had ASD, which equates to a prevalence just above 1%. The odds of having ASD were 4 times higher in boys than in girls. Non-Hispanic black and multiracial children had lower odds of ASD than white children.

Interestingly, parents reported that 40% of all children who were once labeled as having ASD did not currently have it, a finding that suggests over-diagnosis of the condition since there is no known cure.

The reported 1% prevalence is higher than that cited by the previous gold-standard study on the subject, which was published in 2003. It said the prevalence was 1 in 150.

But many urged caution about the apparent change in prevalence. “We don’t know whether the change over time is a result of the change in the actual condition or due to the fact that the condition is being recognized differently,” the CDC’s Ileana Arias told CNN.

The study raises “a lot of questions about how we are preparing in terms of housing, employment, social support — all the issues that many of these people are going to need,” added Tom Insel, who directs the National Institute of Mental Health.

Are you reading this while checking email, chatting on IM, waiting for your purchase to clear PayPal and signing your mum’s birthday card?

If so, please set all that aside for a moment and take note.

A study published in the Proceedings of the National Academy of Science suggests that people who tend to involve themselves in multiple media-oriented activities at the same time perform relatively poorly on tests requiring them to shift attention from one task to another.

To reach these conclusions, Clifford Nass and colleagues at Stanford administered a survey to 262 college students which elicited a history of media utilization and whether or not they tendened to engage in multiple tasks simultaneously.

They collected information regarding the use of computer games, online video and audio, TV, cell phones, text and instant messaging, and computer software like word processors.

After completing the survey, the students underwent a battery of tests in which they had to evaluate certain colored triangles while ignoring other ones, categorize words, alternate between classifying numbers and letters, and press a certain button when they saw a match between 2 symbols presented at different times.

The scientists found that heavy multitaskers executed these functions more slowly than with those who rarely used more than one medium at a time. The multitaskers, it turned out, were more easily distracted by irrelevant information because they retained it in their short-term memories for a longer period of time.

The difference amounted to about a half-second delay on most tests, a difference large enough to cause noticeable problems in everyday life. (more…)

The “silent crisis” known as global warming already kills 300,000 people per year, and that number will double in just 2 decades, according to a report by the Global Humanitarian Forum.

The “Human Impact Report: Climate Change”  was released in anticipation of a meeting  of the United Nations Climate Conference to be held next winter.

The purpose of that conference will be to develop a post-Kyoto climate agreement.

“We are trying to get the world’s attention…climate change is not something waiting to happen. It is impacting seriously the lives of many people around the world,” Forum president Kofi Annan told CNN.

“This threat to our health…to food production… to security…raises political tensions. It will have people on the move — and they are on the move — and many more which will bring tensions,” Annan added.

The report states that the Earth’s atmosphere warmed 1.33 degrees Fahrenheit between 1906 and 2005. Most of the jump transpired in recent decades.

It projects that by the turn of the next century, the Earth’s atmospheric temperatures will jump a minimum of an additional 2.3 degrees Fahrenheit, “no matter what.”

“The suffering documented in this report is only the beginning.” The minimally expected rise, concluded the report, “would be catastrophic.”

Nearly all, 99%, of the 300,000 lives lost each year due to climate change are located in developing countries, which collectively produce about 1% of the world’s carbon emissions. Climate-related deaths due to malnutrition, diarrheal illnesses and malaria dwarf all other weather-related deaths.

The countries most vulnerable to global warming lie in a semi-arid belt extending from the Sahara/Sahel to the Middle East and Central Asia, as well as those in Sub-Saharan Africa, South and Southeast Asia, Latin America and the Arctic.

Australia was cited as the most vulnerable among first-world nations. It is already experiencing the worst 15-year drought in recorded history.

The report says developed countries need to contribute 100 times more funds than they currently devote to help developing nations fight the scourge.

Annan implored nations attending next winter’s meeting to reach a “global, effective, fair and binding” accord on climate change. Those talks could “well be the last chance for avoiding global catastrophe,” he told CNN.

A panel of experts has recommended that the FDA should ban the prescription painkillers Vicodin and Percocet, and that the “safe maximal” dose of Tylenol be reduced significantly.

The panel voted 20 to 17 to ban on the 2 narcotic-acetaminophen combo drugs.

It also recommended that extra-strength Tylenol be made available by prescription only, and that dosing recommendations for children’s Tylenol be reexamined.

The problem with all of them, according to the panel, is acetaminophen, which has long-since been linked to liver damage.

The group recommended that the FDA “send a clear message that there’s a high likelihood of overdose from prescription narcotics and acetaminophen products,” Sandra Kweder of the FDA’s Office of New Drugs said at a press conference.

Acetaminophen overdoses prompted 56,000 emergency room visits, 26,000 hospitalizations and 458 deaths in the 1990s, the FDA reported.  It is also, according to the CDC, by far the most common cause of acute liver failure, which strikes about 1,600 people each year.

Acetaminophen is also found in NyQuil, Pamprin, Allerest and dozens of other OTC remedies for colds and flu, headache, menstrual symptoms, allergies, insomnia, arthritis and other minor ailments.

The panel decided against recommending a ban on OTC drugs containing acetaminophen, since they cause less than 10% of all overdoses with this drug.

Abbott Laboratory’s Vicodin and its generic congeners are the most frequently prescribed drugs in the US, according to IMS Health. Nearly 124 million prescriptions were written for the juice last year alone.

The FDA is not required to follow the recommendations of its panels, though it usually does.

A jury has acquitted W.R. Grace & Company and its former executives of knowingly exposing mine workers and the residents of Libby, Montana to asbestos.

“We at Grace are gratified by today’s verdict and thank the men and women of the jury who were open to hearing the facts,” said Fred Festa, the company’s CEO in a statement obtained by CNN.

Prosecutors had alleged the mining company conspired to “knowingly release” asbestos for decades. “It was a purpose of the conspiracy to conceal and misrepresent the hazardous nature of the…asbestos contaminated vermiculite, thereby enriching defendants and others,” read the indictment.

Best estimates are that Libby residents suffered 200 excess deaths and 1,000 illnesses due to asbestos exposure.

The fine, dusty stuff had blanketed everything in town from big rigs to baseball fields. Libby residents testified that Grace never told them about health risks associated with the stuff.

Grace never denied that asbestos came from its vermiculite mine in town, nor that it had sickened and killed many, but it vigorously denied a conspiracy.

In fact, it claimed that it acted responsibly once it became aware of the problem, and that it paid millions to cover the asbestos-related medical bills of Libby residents.

Asbestosis causes numerous illnesses including mesothelioma, a rare cancer that originates in the lining of the lungs, abdomen and heart.

Grace faced fines of up to $280 million, and certain Grace executives were looking at jail time had the verdict gone the other way.

“I don’t see how they could have gotten out of it,” said Steven Schnetter, who worked at the mine for 17 years before developing asbestosis, a lung disease caused by exposure to asbestos fibers.

When it comes to the early diagnosis of autism, scientists are on a roll.

Last month, a group at Yale showed that autistic children could be differentiated from age-matched controls by their responses to visual and auditory cues in cartoons.

Now, a group at UNC has demonstrated using MRI scans that a specific part of the brain known as the amygdala was roughly 13% larger in autistic children than it was in normally developing kids, even after adjusting for age, gender and IQ.

To reach this conclusion, Joseph Piven and colleagues scanned the noggins of 50 toddlers with autism and 33 age-matched controls that were developing normally.

“We believe that children with autism have normal-sized brains at birth but at some point, in the latter part of the first year of life, (the amygdala) begins to grow in kids with autism,” Piven told CNN.

The amygdala helps people process faces and emotions, a behavior known as joint attention. Piven’s group confirmed that toddlers with big amygdalas had joint attention problems.

“We would basically try to get the child to look one way, we’d turn and point to a clock and see whether or not the child would notice it,” Piven explained. “The 2-year-olds without autism would…see where you are looking and join you but the children with autism, with large amygdalas, would not.”

Autism experts say such findings are critical in developing new ways to diagnose autism and initiate treatment earlier in the course of the disease.

Autism affects about 1 in 150 children. It is the most rapidly growing serious developmental disability in the US. The average age for diagnosis of autism is 3.

The findings appear in the Archives of General Psychiatry.

West Virginia Republican delegate Craig Blair thinks that people who file for welfare, unemployment or food stamps ought to be drug-free. So he introduced a bill requiring applicants for such programs to undergo random drug testing.

He makes the case at notwithmytaxdollars.com.

“The message that we’re trying to send is, first of all, we need to respect taxpayers and how their monies are spent,” Blair told CNN. “Drug addiction is in epidemic proportions, and not only in West Virginia but throughout the United States.”

The bill proposes that people who fail the test would get benefits and 60 days to sober up. A second failed test would result in the loss of benefits for 2 years.

“It seems ironic that welfare and unemployment are both designed to get you back to work and everything, but how is that possible if you’re on drugs?” Blair wondered.

Nine other states are considering similar legislation, although proposals in Arizona and Michigan have either been nixed by the courts or deemed too expensive.

Graham Boyd, director of the ACLU’s Drug Law Reform Project, ridiculed the idea as “typical political theater. [You'd think] people would be more compassionate now that people have lost jobs,” Boyd added.

And the Brookings Institute’s Ron Haskins clarifies that “unemployment is really not a welfare program. It’s an insurance program. (People have) paid into the program each month they’ve had earnings,” he explained to CNN.

But Blair claims he’s been flooded with support for his proposal. The nation’s epidemic drug abuse problem and the tanking economy call for “tough love,” he said.

The Labor Department reports that 5.6 million people collect jobless checks right now, and nearly 32 million get food stamps.

That’s a lot of drug tests, Craig.

By all accounts, Cerrie Burnell has the skills and make-up to be terrific in her new role has co-host for Cbeebies, a BBC children’s show aimed at kids 6 years old and under.

It’s just that Burnell was born with one hand, and the plainly visible disability has roiled some British parents who worry what impact the gestalt might have on their children.

BBC Spokesperson Katya Mira said the network has received at least 25 “official” complaints since Burnell joined the show in January, and that’s not counting dozens more negative comments posted in chat rooms and blogs.

One father complained for example that the hostess forced him to discuss disabilities with his child before he would have preferred.

Mira was quick to add that the BBC has “received 99 appreciations of (Burnell),” according to CNN.

Before joining Cbeebies, Burnell had worked as an actress for theater companies in Manchester, England and Brazil.

BBC’s January news release introducing Burnell did not mention her disability, although it was accompanied by a PR photo in which the right sleeve of her sweater was rolled up leaving the missing lower limb in plain sight.

Burnell has heard the criticism and remains unperturbed.

“It can only be a good thing that parents are using me as a chance to talk disability with their children. It just goes to show how important it is to have positive, disabled role models on CBeebies and television in general,” Burnell told CNN.

And BBC controller Michael Carrington voiced strong support for Burnell. “Cerrie is warm and natural and we think that, in time, all moms and dads and children will love her as much as we do,” he said.