News briefs

Gluten response in people with coeliac disease could lead to diagnostic test

Researchers, including Associate Professor Jason Tye‐Din at the Walter and Eliza Hall Institute of Medical Research, have found distinct markers in the blood of people with coeliac disease that are detectable within a few hours of consuming gluten. The findings, published in Science Advances, cast light upon the long‐standing mystery of what drives the adverse reaction to gluten in coeliac disease, and could lead to the first blood test for diagnosing the disorder. A blood test would be a major improvement on the current approach, which requires people to consume gluten for weeks or even months before undergoing an invasive procedure to sample their small intestine. Researchers discovered the immune markers while assessing patient blood samples during a phase 1 trial of Nexvax2, a potential vaccine for people with coeliac disease. In patients injected with gluten peptides, gastrointestinal symptoms, particularly nausea and vomiting, were correlated with higher levels of interleukin (IL)‐2 in their blood. Subsequent testing found that consuming gluten elicited the same IL‐2 response in people with coeliac disease. Ms Michelle Laforest, CEO of Coeliac Australia, said the finding would be welcome news. “The potential for a one‐off gluten challenge and blood test could make a significant difference to many thousands of Australians who report sensitivity to gluten but have been unable to tolerate the current testing approach.”

https://advances.sciencemag.org/content/5/8/eaaw7756

Major surgery associated with small, long term decline in brain power

Major surgery can be associated with small, long term declines in cognitive functioning equivalent, on average, to less than 5 months of brain ageing, a US study published in The BMJ has found. The odds of substantial cognitive decline more than doubled after surgery, but even more after admission to hospital for a medical condition. Certain disorders, such as stroke, can lead to a large “step change” in cognitive decline, and concerns that surgery might also induce such changes have led some patients to refuse beneficial procedures, say the researchers. Few studies have examined the impact of major surgery on cognitive decline, and most have relied on single pre‐operative assessments of cognitive function rather than tracking cognitive status over time. The researchers therefore analysed data for 7532 British civil servants enrolled in the Whitehall II study of the impact of social, behavioural, and biological factors on long term health. All were aged 35–55 years in 1985 and had received up to five cognitive assessments during 1997–2016. A total of 8982 major hospital admissions (requiring a stay of at least two nights) were identified in hospital statistics: 4525 operations, 4306 medical admissions, and 151 strokes. Among the 7532 participants, 4954 had no major admissions to hospital, but 1250 had surgical admissions, 715 medical admissions, and 613 had both. After accounting for age‐related cognitive decline, the authors estimated that major surgery was associated with a mean additional decline equivalent to fewer than 5 months (0.35 years) of ageing. Admissions for medical conditions (1.4 years) and stroke (13 years) were associated with far greater additional declines. The odds of substantial cognitive decline were increased 2.3‐fold by a hospital admission for major surgery and 6.2‐fold by admission with a medical condition. Substantial cognitive decline was measured in 5.5% of patients who had been admitted for a surgical procedure and 12.7% of those treated in hospital for a medical condition, compared with 2.5% of people who had had no major hospital admissions. As this was an observational study, no firm conclusions can be drawn about cause and effect, and hospital admissions were possibly a surrogate measure for ill health, the researchers point out.

https://www.bmj.com/content/366/bmj.l4466