Losing Our Mind to the Pandemic

Today I diagnosed another shielding patient with cognitive impairment – almost certainly Alzheimer’s Dementia. It was the same story as the other patients I have diagnosed recently. Her memory was pretty good before lockdown last year but when COVID – 19 came along everything changed. Social interactions reduced, clubs and activities stopped, she became less active, not wanting to put herself at risk of catching Covid. Health anxiety increased and the usual mechanisms to relieve these stresses weren’t there anymore. Gradually she became more forgetful, days rolled into one another and the date and time started to matter less. By the time I met her she was unable to tell me what day it was and could not retain any information for longer than a few seconds.

Alzheimer’s is a devastating disease that robs patients of their memory, concentration, social abilities and gradually sends them to an early grave. The prognosis for this terrible disease is poor; we have no cure and the drugs we do have are only mildly effective at slowing the disease process down.

Sadly, Dementia prevalence is on the increase. In 2019 there were 850,000 people in the UK with dementia which affected 1 in 14 people over 65yrs old. With the current prediction by the London school of economics being that over 1.5million people will suffer from dementia by 2040, and Alzheimer’s represents 50-75% of all dementia cases. It affects women twice as commonly as men and disease prevalence is higher in wealthier countries than developing countries. Importantly this information was written before the covid19 pandemic.

So how does COVID 19 change things? For those unlucky enough to have suffered from severe COVID infections and end up critically unwell, the risk of delirium (acute confusion) is 55%. This is much greater than the rate of delirium with other critical illnesses which stands at 33%. Sadly, 30% of those who develop delirium enter a downward spiral with their memory over several months and go on to develop dementia. Scientists are already predicting a rise in dementia cases based on this information and follow up research on patients post covid is already underway. A six month study reported by the BBC in April links an increased risk of dementia post COVID which is higher than the average population and the risk is greater depending on disease severity, sadly as many as 1 in 10 people with covid encephalophy – a serious complication – may end up with dementia.

On top of this we don’t know if the social isolation, increased inactivity and lack of stimulation from clubs and hobbies will increase the risk of dementia in the population who are not infected with COVID-19. From my experience as a GP it certainly looks likely.

So what can we do to help reduce our risk of dementia? Firstly its worth noting that some of the things which prevent us from developing dementia also reduce our risk of severe COVID-19. Namely, exercise, stopping smoking, healthy diet and keeping a healthy weight. In addition to this some regular brain training is worthwhile with learning a new language and practicing art top of the list for the most beneficial past times. A study in the BMJ reported that 4 in 10 cases of dementia can be prevented or delayed by targeting a set of risk factors (poor education, hypertension, hearing deficit, smoking, obesity, diabetes, depression, physical inactivity and low social contact).

Vitamin D deficiency has been implicated as a risk factor for severe COVID infection and also seems to increase your risk of developing dementia by 50% so it’s definitely worth keeping this topped up.

Diet wise there is evidence that the Mediterranean diet helps reduce cognitive decline most likely through the increased antioxidants present in the large variety of fruit and Veg, reducing obesity and cardiovascular risk, lowering inflammation in our body and enhancing the microbiome.

In fact patients admitted to hospital with severe COVID 19 were found to have dysbiotic gut microbiomes which mean that they lack the diversity of microbes we appear to need to remain healthy. It’s therefor no surprise that dementia patients also appear to lack this diversity in their guts.

How do we improve the diversity of microbes in our guts? Through a diet high in fruit, veg, seeds nuts, herbs, spices and wholegrains; by sleeping 7-9hrs a night, exercising regularly and keeping our weight down and reducing stress.

I now feel like I have gone full circle! It turns out that the same things that help keep our microbiome healthy our weight and cardiovascular risk low, and reduce the likelihood of us developing severe COVID infection will also reduce our risk of dementia too. Add to this some vitamin D, social interaction, education, brain training and management of hearing loss and we can all hope for a longer healthier life free of memory problems.

References

1. Mediterranean Diet, cognitive function, and dementia – a systematic review; Epidemiology; Jul 2013; 24; 479-489
2. 10 mins of social interaction improves wellbeing in dementia care; Alzheimers society; 27/7/2018.
3. Physical inactivity, cardio metabolic disease, and risk of dementia: an individual participant meta -analysis. Mike Kivimaki et al; BMJ 2019; 365:1495
4. 4 in 10 dementia cases could be prevented or delayed by targeting risk factors – report says. BMJ 2020; 370; m3050
5. Language lessons to help protect against dementia; BMJ 2016; 354; 5039
6. Brain training, exercise and healthy eating slow cognitive decline in elderly people at risk, study finds; Susan Mayor; BMJ 2015; 350; h1386
7. Gut microbiota composition reflects disease severity and dysfunctional immune responses in patients with COVID-19; Yun Kit Yeoh et al; GUT; Vol 70; issue 4
8. Relationship between dementia and gut microbiome – associated metabolites: a cross sectional study in Japan; Naomi Sami et al; Scientific Reports; 10; article No 8088; 2020