Géraud Dautzenberg

Summary and general discussion

7 The natural course of the disease to be detected must be known. As explained earlier cognitive impairment should be viewed as a state, not a disease. The underlying aetiology is the disease; therefore (often) the natural course of cognitive functioning is known when this aetiology is known. This applies particularly when a state of dementia is attained. For the cognitive state of MCI, this is less true, as the aetiology is often less clear. It is not a prodromal state of dementia but a probability state of converting to dementia and can have different aetiologies that can have different courses compared to dementia. It is known that a substantial proportion of patients with MCI will not convert to dementia, and for some patients, even the cognitive complaints diminish. Patients with MCI generally have a higher probability of developing dementia in the near future compared to people without an MCI in their history. Even if the patients seem to have recovered clinically, functional recovery may not be complete. This could be partly due to residual cognitive symptoms. Does the above imply that Wilson and Jungner’s criterion is not fulfilled for cognitive impairment? We don’t think so. Strictly speaking, if the aetiology is known, the global natural cause of the disease is also known. The MoCA can even be of added value in understanding the course of cognitive impairment to see whether it progresses, stabilises, or even diminishes. Therefore, by using the MoCA one can predict future courses better for patients with cognitive impairment. 8 There must be agreement as to who should be treated. As with criterion 2, we have to clarify what treatment should be considered. Adding to the arguments mentioned in criterion 2, we want to include, from the perspective of the MoCA, referral to a memory clinic as treatment. From this perspective, we add supporting motivation to this criterion 8 of Wilson and Jungner through our study presented in Chapter 5. Although one can (still) debate what kind of ‘treatment’ the different suspected and triaged patients should receive, we substantiate arguments on how to use the MoCA for who is and is not to be referred to a memory clinic (‘treatment’) and who is to be monitored actively. 9 The cost of detection, diagnosis, and treatment must be in an acceptable proportion to the cost of health care as a whole. In Chapter 5, we demonstrate the benefits of using the MoCA as a screener. This brings not only advantages in cost as expressed by money, saving €1000 per avoided false positive, but also for the patients (e.g. less burden in time and stress) as well as for the clinic (e.g. using the facilities more efficiently, shorter waiting list).

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