Can surgery to flush out toxic proteins 'reverse' dementia?

Could a two-hour operation to ‘replumb’ blood vessels in the neck stop dementia in its tracks – something no drug has been able to do?That’s the tantalising prospect thrown up by results of a new trial, in which 83 patients in China with advanced dementia underwent the procedure and saw what researchers claim were ‘significant’ improvements in their condition.It brings the total number of dementia patients in China to have had the experimental surgery to more than 2,000, with anecdotal reports of bedbound patients walking and communicating with loved ones again after the operation.But the treatment is not without controversy, with many of the operations done on a private basis on extremely ill patients whose desperate families handed over tens of thousands of pounds in the hope that it would work.As Good Health reported in April, Chinese authorities banned the surgery (unless as part of a research project) last year, over concerns about the lack of evidence on safety and effectiveness.Nevertheless, the research is being closely monitored by dementia experts globally.The procedure is relatively straightforward, likened by doctors to clearing a blocked drain to ‘flush out’ toxic proteins that are thought to cause dementia in the first place. Called lymphatic venous anastomosis (LVA), this type of treatment is already widely used on the NHS to tackle lymphoedema, swelling of the arms and legs due to a build-up of fluid.The condition develops when surgeons remove lymph nodes (tiny nodules that filter out waste products from the bloodstream) to stop breast cancer spreading.Everyone experiences dementia differently. Use this checklist to help you make a note of your symptoms before you talk to your GP. Researchers said: ‘All the patients exhibited enhanced alertness and vitality, characterised by increased responsiveness and improved engagement' (picture posed by models)With the LVA procedure, a tiny incision is made under the armpit, then surgeons stitch the lymph vessel that’s full of fluid to a nearby vein – allowing the excess fluid to drain into the bloodstream. The benefits are well-established.Now, researchers are experimenting with a similar technique, attaching lymph vessels in the neck to nearby veins in order to treat dementia. The brain has its own lymphatic drainage system, to dispose of waste and detritus left by cell activity.As we age, the system becomes sluggish, allowing harmful proteins to accumulate. These can form deposits in the brain – amyloid plaques – which disrupt communication between cells and in turn harm cognitive function, eventually leading to dementia symptoms such as memory loss and confusion.The surgery being investigated involves making a small incision in the neck just below the jaw. This gives the surgeon access to the deep cervical vein – which drains blood from the neck – where it runs parallel to a lymphatic vessel.A hole is cut into the vein and the lymphatic vessel is stitched into place. The theory is that plaque-causing proteins can then drain away. The operation, which is done under general anaesthetic, takes about two hours.This idea – flushing toxic proteins out of the brain – is similar to how some of the newer Alzheimer’s drugs (such as lecanemab and donanemab) work. They bind to the damaging proteins and break them down for them to be transported out of the brain through the circulatory system.But the drugs aren’t available on the NHS, partly due to limited benefits and side-effects that include brain bleeds.In the latest study, doctors at Xi’an Fengcheng Hospital in Shaanxi, China, operated on 83 patients with advanced dementia.In the nine months after the surgery, there was a significant improvement in blood flow to the brain (a reduced supply of oxygen-rich blood to the brain can contribute to dementia).Meanwhile, 40 per cent of the patients improved their scores on the Mini-Mental State Exam – which measures attention, recall and language – while the rest were unchanged.In the Journal of Alzheimer’s Disease last month, the researchers said: ‘All the patients exhibited enhanced alertness and vitality, characterised by increased responsiveness and improved engagement.’ They added: ‘Attention and executive functions [such as memory and planning] also significantly improved, enabling more effective interaction with caregivers.’Side-effects, they said, were mild, mostly involving temporary wound pain at the surgery site.But some leading UK dementia experts are highly sceptical. Robert Howard, a professor of old age psychiatry at University College London, says close examination of the data reveals the benefits are tiny.‘In the study, the MMSE scores increased from an average of 3.01 to just 4.45,’ he said – 30 being the maximum. ‘So even after surgery, these patients were still severely impaired by their dementia. Also, everybody knew they were getting the real surgery, rather than a sham procedure, which means any increase is probably due to the placebo effect.’Even if the surgery does have a positive effect, he said, it may well be short-lived as whatever is driving the production of amyloid proteins has not been addressed.There are more than 20 clinical trials under way on this surgery in China. It is also being investigated in the US and Singapore – where four people have had the operation.