Weather check 'could predict' A&E injury rates

Taking the temperature outside A&E could give staff an accurate way to predict number of injuries and who will suffer them.Experts know that extreme weather can affect A&E patient numbers.Warwick University researchers found that even 5C falls or rises could make a difference to injury rates.Rates for children were up to 70% higher in summer compared with winter, the Emergency Medicine Journal reported.Many trusts plan ahead for winter, when the arrival of frost, snow and ice, as well as flu and pneumonia, is traditionally linked to busier shifts.The study of 60,000 patients found that each 5C drop in minimum temperature during the day meant a three per cent rise in serious accidents to adults.Heat of summerThe arrival of snow and ice led to an eight per cent rise, as the number of slips, trips and car accidents rose.However, the study found other increases linked to the heat of the summer, often viewed as a slightly calmer period in emergency departments.

Even among adults, every five degree centigrade rise in maximum temperature during the day, and additional two hours of sunshine, meant a 2% rise in the rate of serious injury.This effect was particularly noticeable in children, who are more likely to get injured while playing outside during the warmer months.For them, a 5C rise meant a 10% increase in injury cases, and two hours of extra sunshine boosted cases by six per cent.While these connections were made by comparing records of hospital admissions with historical weather data, the researchers are convinced that the principle could be used to help emergency teams plan ahead for days when their workload is likely to be higher.They wrote: "This model could clearly be used to provide predictions of daily admissions, with clear implications for the scheduling of staff and other resources at UK trauma-receiving hospitals.

"The challenge for the future is to improve forecast accuracy further in order to provide sufficient time for the detailed planning and allocation of resources that would be necessary to implement these models."

Professor John Heyworth, president of the College of Emergency Medicine, agreed that the detailed study could help clinical teams know what to expect on any particular day, although he questioned whether the current accuracy of medium-term weather forecasts was good enough to justify staffing changes.

He said: "We've always known that there is increased activity in emergency departments during winter, but in recent years, we've noticed that this doesn't really diminish during the summer months - we remain busy all year round."If you have your emergency department set up to deal with this expected load, then you can deal with extra cases due to weather conditions.

Magnetic activity in brain 'diagnoses stress disorder'

A one-minute test appears to diagnose post-traumatic stress disorder with an accuracy of 90%.

The test measures the tiny magnetic fluctuations that occur as groups of neurons fire in synchrony, even when subjects are not thinking of anything.

These "synchronous neural interactions" have already been shown to distinguish signals from subjects with a range of disorders including Alzheimer's.

The latest work is reported in the Journal of Neural Engineering.

The brain's signals are effectively a symphony of electrical impulses, which in turn drive tiny magnetic fields.

Researchers have measured and mapped these fields, in a pursuit known as magnetoencephalography, since the late 1960s. It has already been used to diagnose tinnitus, and can even predict when people will make mistakes.

Apostolos Georgopoulos, at the University of Minnesota in the US, developed the synchronous neural interactions (SNI) approach as a means to mathematically untangle the myriad signals that magnetoencephalography produces.

In 2007, he led a group that showed that SNI signals can distinguish between subjects with multiple sclerosis, Alzheimer's disease, schizophrenia, Sjögren's syndrome, and chronic alcoholism.

One to watch

Professor Georgopoulos and his colleagues have now used the approach to assess its accuracy in diagnosing post-traumatic stress disorder (PTSD).

The team recruited 74 military veterans who had already been diagnosed with PTSD alongside 250 members of the public.

The subjects were asked simply to stare at a dot for up to a minute while the magnetic signals were collected - a measure of the brain "at rest".

This is in contrast to preliminary results reported in 2009 that functional magnetic resonance imaging, or fMRI, may be useful in diagnosing post-traumatic stress disorder.

In that work, subjects were exposed to images of combat situations.

The SNI approach proved 90% accurate in discerning which subjects had PTSD.

"The excellent results obtained offer major promise for the usefulness of the SNI test for differential diagnosis," the team wrote, "as well as for monitoring disease progression and for evaluating the effects of psychological and/or drug treatment."

Dr Neil Greenberg, a researcher in military psychiatry at King's College London, expressed doubt that a clinical test of this sort solves the principal challenge in diagnosis.

"The main challenge with PTSD - with the military, emergency services, or journalists - isn't diagnosing it," he told BBC News.

"It's with getting people who might have the condition to come forward and have an assessment and treatment.

The approach teases out signals from neurons firing together

"If someone could go out and point a device at a hundred people and tell which of them would actually benefit from treatment but aren't going to come forward and get help, that would be useful."

He added that, in current practice, a treatment programme would in any case be decided through the same lengthy behavioural questionnaires that are used to diagnose the disorder.

Rajendra Morey of Duke University, a researcher into the neurological basis of PTSD and other disorders, said that such reluctance to come forward is endemic across medicine, adding that the SNI approach "has a lot of merit" in the formal study of brain disorders.

"We already have behavioural measures to diagnose PTSD, but I think the strength here is that it can be done very rapidly and objectively," he told BBC News.

"The sort of stigma that PTSD is some kind of weakness may be overcome to some extent by establishing, by further confirming, that it's really changes in the brain and that we have objective measures of these changes.

"I think it's something that the scientific community, especially in PTSD and mental health research, will watch closely."