Cognitive Function Testing

Back in the 80’s one either had diabetes or you were OK. The same kind of thinking happens with dementia. You’ve either got it or you haven’t. But not everything is black and white. Grey matters. That ‘grey’ zone between having good cognitive function and being diagnosed with dementia is a long, slow slippery slope. In fact, changes in cognitive function can be detected up to 40 years before a diagnosis.

That is why having a Cognitive Function Test when you’re in your 40s or 50s is vital. This test is very accurate, assessing three attributes of cognition, namely episodic memory, executive function and attention. What’s more a subjective view that you are OK or not OK doesn’t correlate well with this actual measure of cognitive function. So, if you think your memory is fine it might be getting worse and if you think it is getting worse, you may not have a problem. The biggest problem of all is people burying their heads in the sand, not taking the Cognitive Function Test because they are scared of the result, or think there’s nothing they can do anyway. Nothing could be further from the truth. The earlier you make changes the easier it is to regain full cognitive function. The same is true with studies of the brain.

Grey matter – why your brain needs a service

Keeping your brain in shape is no stranger than servicing your car, or keeping your muscles taut or your body in trim. Why, then, do so many of us do so little to maintain the health of our brains? More than any other organ of the body, your brain is key to living a happy, fulfilling and pain-free life.

This 3–pound mass of mainly fat and water nestling in our skulls is not only the most complex and mysterious part of us. It also is the most regenerative, hardwiring a new neuronal connection every minute, and because of this, it is the most energy- expensive. On a sedentary day, your brain will consume as much as 40 per cent of all the calories you eat, and think an estimated 60,000 thoughts! More than any other organ of the body, it depends on a second-by-second supply of the right nutrients.

The brain is not just a cognitive wonder, a world within a world; it’s also an organ, and just like your heart or lungs, your doctor can examine it for damage. Unfortunately, this procedure is neither as easy nor as inexpensive as taking your pulse or blood pressure, so your doctor will not request a brain physical unless you are showing significant signs of memory decline. In an ideal world, if money was no object, people would get scanned as soon as cognitive function declines, for example if you’re in the yellow, orange or red zone on the Cognitive Function Test.

There are three kinds of scan available (CT, PET or SPECT and MRI), all designed to see if there are any areas of damage, abnormality or ‘shrinkage’. Nowadays MRI scans are the gold standard. This might sound scary, but the brain does tend to shrink with age. In fact, it’s common for 20 per cent of brain cells to die over a life-time, so that by the age of 70, most people’s brains have shrunk by 10 per cent. A gradual loss of control of the complex orchestra of hormones and neurotransmitters often accompanies this shrinkage, leading to diminished brain power, slower memory retrieval, a reduced sex drive, less energy, less motivation and fewer emotional highs. But it doesn’t have to be like this.

How dense is your brain?

Your brain is made of two kinds of matter – grey and white. Grey matter, spelt gray in the US, is the kind of matter found in the body of brain cells (neurons). White matter is more to do with the tentacle like extensions that reach out and connect brain cells together. These are white because they are fattier, rather like a tubular underground system, surrounded by fatty membranes, reach out to the next station. In this analogy the station is more grey matter and the train lines and tunnels are more white matter, but they are both throughout the brain. See figure below. Scans can measure the density or volume of the grey matter and the integrity of the white matter. Less dense grey matter means brain cells are dying and thinning out. Less integrity of white matter means less viable connections.

Then there’s the areas of your brain, shown in the diagram below. Of particular concern is the thickness or density of the medial temporal lobe (MTL), in the middle, which includes the hippocampus and is also sometimes called the hippocampal region.

Shrinkage in this area is what changes a diagnosis of mild cognitive impairment (MCI), sometimes called pre-dementia, or dementia, both of which can be diagnosed just from poor cognitive function, into a diagnosis of Alzheimer’s. Alzheimer’s accounts for two thirds of cases of dementia. Much of the rest is called cerebrovascular dementia which includes strokes and mini-strokes called transient ischemic attacks, or TIAs. Scarring in the brain from TIAs id often found in those with medial temporal lobe shrinkage.  This means there are problems in the circulation of nutrients, including oxygen, into the brain.  Not only do these diagnoses overlap, but also just about every risk factor for Alzheimer’s is a risk factor for both cerebrovascular dementia, and for cardiovascular disease. Linking them all together is homocysteine B vitamins and the omega-3 fat DHA which makes up over 90% of the structural fat of the brain.

A study of healthy 50-75 year olds who were given 2,200mg a day of omega 3 fish oils for 6 months not only reported significant increase in executive functions, one aspect of cognition that is a hallmark of Alzheimer’s, but also beneficial structural changes in white matter integrity and grey matter volume in the brain.[1] The cognitive improvement correlated with blood levels of omega-3.

The H factor – Test Your Homocysteine

Blood homocysteine should always be measured if your cognitive function is not ideal. An ideal level would be 7mcmol/l but if it’s raised over 11mcmol/l, this is associated with an increased rate of brain shrinkage, cognitive decline, as well as increased risk for strokes (see article ‘The H Factor’ here] ). A recent study found a strong correlation between raised homocysteine and both blood vessel disease in the brain and cognitive function opening up the possibility that homocysteine leads to damaged blood vessels in the brain, which leads to cognitive decline. Those in the quarter with the highest homocysteine levels were ten times more likely to have cognitive impairment and 17 times more likely to have blood vessel disease.[2]

The great news is that homocysteine can be easily lowered with B vitamin supplementation giving folate (the B vitamins in greens), B6 and B12. Vitamin B12 is often the most critical since 3 in 5 people over 60 have low blood levels despite apparently eating enough.[3] An irish study showed that 12% over 60 had low B12 levels.[4] It’s found in meat, eggs, fish and milk. The issue is less about diet and more about decreasing absorption with age, made worse by various medications including antacids[5] and metformin[6] . Diuretics used for high blood pressure may also increase homocysteine.[7] Stomach acid is needed to absorb vitamin B12 and levels decline with age. Thus, the level of B12 needed to lower homocysteine is in the order of 500mcg which is 200 times the RDA. Folate levels are also a strong predictor of both dementia and strokes and giving folate supplements has been shown to decrease this risk.

Testing Cognitive Function from age 50 is key

Therefore the best way to future-proof yourself from dementia is to test your Cognitive Function in your 40s or 50s using our Cognitive Function Test. If you’re in the green zone all is good. If you’re in the yellow, orange or red zone it’s important to both test your homocysteine level and take action to keep it below 10, and to join COG-NITION to target your domains of risk and bring down your Dementia Risk Index.

By completing the Cognitive Function Test you are joining our grassroots research initiative to find out what really works for preventing cognitive decline. We share our ongoing research results with you to help you make brain-friendly choices.

Please support our research by becoming a Friend of Food for the Brain.

References

[1] Witte AV, Kerti L, Hermannstädter HM, Fiebach JB, Schreiber SJ, Schuchardt JP, Hahn A, Flöel A. Long-chain omega-3 fatty acids improve brain function and structure in older adults. Cereb Cortex. 2014 Nov;24(11):3059-68. doi: 10.1093/cercor/bht163. Epub 2013 Jun 24. PMID: 23796946.

[2] Teng Z, Feng J, Liu R, Ji Y, Xu J,
Jiang X, Chen H, Dong Y, Meng N, Xiao Y, Xie X and Lv P (2022) Cerebral small vessel disease mediates
the association between homocysteine and cognitive function. Front. Aging Neurosci. 14:868777. doi: 10.3389/fnagi.2022.868777

[3] Vogiatzoglou A, Refsum H, Johnston C, Smith SM, Bradley KM, de Jager C, Budge MM, Smith AD. Vitamin B12 status and rate of brain volume loss in community-dwelling elderly. Neurology. 2008 Sep 9;71(11):826-32. doi: 10.1212/01.wnl.0000325581.26991.f2. PMID: 18779510.

[4] Laird EJ, O’Halloran AM, Carey D, O’Connor D, Kenny RA, Molloy AM. Voluntary fortification is ineffective to maintain the vitamin B12 and folate status of older Irish adults: evidence from the Irish Longitudinal Study on Ageing (TILDA). Br J Nutr. 2018 Jul;120(1):111-120. doi: 10.1017/S0007114518001356. PMID: 29936926.

[5] Maes ML, Fixen DR, Linnebur SA. Adverse effects of proton-pump inhibitor use in older adults: a review of the evidence. Ther Adv Drug Saf. 2017 Sep;8(9):273-297. doi: 10.1177/2042098617715381. Epub 2017 Jun 29. PMID: 28861211; PMCID: PMC5557164.

[6] Laird EJ, O’Halloran AM, Carey D, O’Connor D, Kenny RA, Molloy AM. Voluntary fortification is ineffective to maintain the vitamin B12 and folate status of older Irish adults: evidence from the Irish Longitudinal Study on Ageing (TILDA). Br J Nutr. 2018 Jul;120(1):111-120. doi: 10.1017/S0007114518001356. PMID: 29936926.

[7] Morrow LE, Grimsley EW. Long-term diuretic therapy in hypertensive patients: effects on serum homocysteine, vitamin B6, vitamin B12, and red blood cell folate concentrations. South Med J. 1999 Sep;92(9):866-70. doi: 10.1097/00007611-199909000-00003. PMID: 10498160.