Why I am shit scared?

Is society ready for population screening for the pre-symptomatic diagnosis of Alzheimer's disease? #ThinkSpeak #Dementia #Alzheimers

As I get older, and more forgetful, I wonder if I will be one of the unlucky ones that develop Alzheimer’s disease (AZD)? I used to pride myself on having a very good memory, not any more. My memory earned me the nickname ‘Xerox’; my good friend ‘Patch Collingwood’* was responsible for the label. The prospect of dying with a dementing illness scares the shit out of me. We define ourselves by our memories; delete them and we either become moored to a fixed point in time or we become a rudderless boat floating from one experience to another without any reference to the past, present or future. 

Rudderless

My anxiety of developing a dementia is not that far-fetched; my maternal aunt died with with advanced AZD and the current background risk of me developing a dementia is not far off 1 in 3. However, there is some light on the horizon; it is becoming increasingly clear that with the appropriate screening tools we can now diagnose AZD in the presymptomatic phase. In the near future this will involve a simple mouth swab that could be sent off in the post to one of the online genomics companies. They will run a simple whole genome screen and give you a AZD risk score, and possibly risk scores for a whole raft of other diseases. If your AZD risk score is above a certain threshold you will have the option of having a lumbar puncture, and possibly an MRI and PET study, performed. The results of the spinal fluid and imaging studies will be used to diagnose you as having AZD, or hopefully as not having AZD. If you have AZD you will then be offered a battery of neuropsychological tests to see if you have early cognitive problems; if you do and these are consistent with an acquired cognitive problem you will be diagnosed as having clinically-apparent AZD. Does this sound far fetched? It may do to you, but if the current clinical trial programmes testing monoclonal antibodies against the beta amyloid protein, hypothesised to cause AZD, show that regular infusions can delay the diagnosis, or slow the progression, of AZD then you would want to know if you had AZD ASAP so you can do something about it, i.e. go onto one of these treatments. No doubt ‘Time Matters’ will be as equally applicable to AZD as it is to stroke and MS.

The question is whether, or not, you, society and the medical profession are ready to implement this scenario. I say this from my experience in the field of multiple sclerosis. In MS we typically diagnose people with their disease before they develop overt cognitive impairment, or become demented, and despite having access to effective disease-modifying therapies a large number of neurologists are still prepared to wait-and-see, or leave their patients with smouldering disease on less effective, albeit safer, platform therapies. So even if we could target AZD early I am not sure if we, the medical profession, will adopt a preventive approach. Therefore I would urge society, and the medical profession, to start the debate now and get us used to the idea of population screening and the treatment of AZD in the asymptomatic phase. Preparing the field for medical innovations targeting AZD are around the corner.

A good analogy, from the medical profession, is the adoption of innovations by some of us that have worked in cardiovascular disease to reduce your chances of having a myocardial infarction and/or stroke. I say some of us as I am still debating starting a statin despite having found out I have a raised cholesterol.

What about now, in the pre-DMT AZD era? Would you want to know your risk of getting AZD despite there being no licensed DMT? You can get a partial risk score already by simply sending off your DNA to one of genomics companies. Knowing you were at increased risk of developing AZD may change your behaviour. It may nudge you to take brain health more seriously, i.e. exercise, sleep, diet, smoking, alcohol, hypertension, etc. We know that an unhealthy lifestyle, and comorbidities, are associated with an earlier diagnosis of AZD. On the other hand some people would argue that knowing that you are high risk of developing AZD would simply medicalise the problem and cause you to become anxious and depressed. Those with hypochondriacal tendencies would interpret every forgotten word, or fact, as the beginning of their disease. A much better solution would be to reflect on your life and assume that you are at risk of developing AZD, just like everyone else is, and make an effort to change the way you live to reduce your chances with the hope that you will die of something else before you develop AZD. Or you can bury your head in the sand and hope for the best.

*Patch (aka John Collingwood) got his nickname from his balding head. Although his pattern of baldness was a patch, it subsequently became a runway and is now almost a desert.