Thanks to improved understanding of the underlying biology of Alzheimer’s disease (AD) and the factors that lead to dementia, we know that the first signs in the brain of AD begin a long time before symptoms do. Scientists also now think that this is probably the best stage to modify the disease progression. But dementia at this early stage tends to be underdiagnosed for a variety of reasons. One reason is that there is often a lack of time during doctors’ visits where the signs might be identified, as well as a lack of training and diagnostic tools at doctors’ disposal. Also, due to the fact that there are very few pharmacological treatments or social services to offer, doctors might feel unwilling to bring it up. The stigma that surrounds dementia, meanwhile, which is still very common in many communities, might also lead to doctors’ reluctance to talk to their patients about it. Doctors who do attempt to discuss cognitive decline with patients might meet resistance, with patients unwilling to hear about it because they didn’t go to the doctor for that reason.
This has bad consequences, the worst of which being that patients are not offered access to potentially helpful treatments and support. Nor are they given the opportunity to make financial or other personal decisions while they still have cognitive capacity. And of course, the lack of early diagnosis deprives medical science of the patients that could potentially be recruited to help advance AD research via clinical trials, whether for medicines or dietetic interventions, for example. Indeed, the disappointing results of clinical trials carried out in individuals with dementia have led researchers to believe that these interventions come too late; earlier action would offer better chance of success.
The MOPEAD project compared four different ways of identifying and engaging with people in the community with prodromal AD (very early form of Alzheimer's when memory is deteriorating but a person remains functionally independent) and mild AD dementia. They carried out this exercise in five different European countries; this geographical diversity was important because of the differences that exist between nations in terms of socioeconomics, health systems, and cultural backgrounds. The project established regional hubs in Slovenia, Spain, the Netherlands, Germany and Sweden, where they implemented, tested and evaluated the four models for patient engagement. Ultimately, they screened 2,000 people aged 65-85 years who had never received a dementia-related diagnosis, the objective being to pre-screen at least 100 individuals per strategy per country.
The four pre-screening strategies, for which a positive results suggest someone is at high risk for having a cognitive impairment, included an online AD citizen science platform, an open house initiative at memory clinics, patient engagement at primary care and patient engagement during visits to diabetes clinics. A positive result during pre-screening would lead to a person being offered a diagnostic test at a MOPEAD memory clinic, the next step. However, a positive result did not always imply AD; it might be found during the second stage of the process that the person is suffering from mental impairment due to depression brought about, for example, by grief.
The four strategies
The first strategy used web searches to pick up on tell-tale words that indicate that someone, or someone close to them, was having memory problems. For example, when someone searched for certain keywords like ‘memory problems’, ‘disorientation’, ‘Alzheimer’s’, ‘dementia’ or ‘brain’, they would be presented with an advertisement where they would be redirected to a page requesting more information (to establish inclusion criteria). They could then take a test, the results of which would lead to an invitation to a memory clinic.
The second strategy was open days at memory clinics where members of the public would be invited to have their memory checked. Neuropsychologists would assess them, and give them more information about their symptoms and potential causes.
The third strategy involved engaging with primary care doctors to train them to assess people who they suspect to be at risk. There were some criteria that patients had to meet: they must be over 65, not be taking certain medications, or be suffering from certain conditions. For example, people who are more socially isolated are also at increased risk. Finally, specialist doctors at diabetes clinics would be engaged in the same way as the primary care doctors. The rationale behind this fourth strategy is that thanks to the high oscillations of blood sugar experienced by people with type 2 diabetes, diabetics have a much higher risk of developing dementia.
Those whose symptoms were deemed potentially related to Alzheimer’s would be referred for CSF (cerebral spinal fluid) test and MRI (magnetic resonance imaging). A diagnosis will lead to them receiving a prescription for one of four medications, which are only effective in early Alzheimer’s and work on the acetylcholine receptors.
This 2-step strategy allowed the project to calculate the positive predictive value of positive pre-screening from each strategy. The number of people enrolled and the proportion of those with positive pre-screening results varied across strategies. The MOPEAD consortium concluded that the different strategies should not be mutually exclusive but should be considered complementary, since they target different populations. The web search strategy and the open house strategy showed great potential to engage large numbers of younger people, whereas the patient-based strategies (primary care doctors and diabetes clinics) engaged fewer people, but those that it did engage were older and at higher risk of having cognitive impairment. These learnings will be very useful to inform policy-makers and the pharmaceutical industry in the design of future screening campaigns for AD, or strategies to engage participants in AD clinical trials.
The most cost-effective of the four patient engagement strategies appeared to be the diabetes clinic setting, followed by primary care. However, these care settings have capacity problems for dementia diagnostics, and as such, the web-based and open house strategies could ultimately be more cost-effective.
As part of the work of MOPEAD, the researchers also surveyed 343 primary care doctors to gauge their attitudes to early identification of AD (they are largely in favour) and their feelings about diagnosing early cases themselves (reluctance, based on lack of treatments). Other interesting findings that emerged from the surveys included the perception that reimbursement of diagnostic procedures differed between MOPEAD’s sites. Non-pharmacological treatment options were widely accepted by GPs (85% considering them beneficial) despite a high proportion of the respondents indicating that they were not sufficiently available.
Spreading knowledge, recommendations for policy makers
Through its dissemination and clinical activities, MOPEAD raised awareness among the general population, healthcare providers and policy makers of the benefits of patient engagement in early detection of AD. The clinical activities generated a wealth of data that has been gathered into a harmonised database of demographic, cognitive and medical data on 2,847 individuals. In a subset of 402 individuals, extensive neuropsychological, functional, genetic and neuroimaging data are also available (as the lumbar puncture was an optional procedure, CSF biomarkers data are available just in a subgroup of participants).
The strategies and protocols deployed in MOPEAD can be used in the future by healthcare systems trying to overcome AD underdiagnosis. It has been very useful to delineate the obstacles that currently stand in the way of early diagnosis of AD in Europe, namely the lack of motivation for early diagnosis, both in the general population and among medical practitioners. Future policies that aim to address these hidden cases should take this into account.
The comparison between the different strategies also provided valuable information, and one of the consortium’s conclusions was that a web-based strategy combining and online marketing campaign and online cognitive testing could pave the way for future initiatives in an increasingly technological world. MOPEAD also showed that cognitive impairment is a very prevalent clinical feature in patients with type 2 diabetes. This is an important finding not only to identify hidden groups of people with AD in the community but also to improve the global clinical management of diabetic patients.
The team produced recommendations for policymakers and medicines regulators based on their findings, taking into account existing recommendations made over the years by the European Commission, the World Dementia Council, World Health Organisation, OECD, Alzheimer’s Disease International, Alzheimer Europe and others. The big takeaway for policy makers is that not only will early diagnosis of people with mild cognitive impairment or early AD improve the quality of life of these people and their carers, it will also prepare the ground for modifying therapies for early stage AD, if and when they reach the market.