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Advanced Neurologyurology
Advanced Ne BRRS: A screening and monitoring tool for better prognosis in AD

network damage would have had already taken place before pathological mechanisms underlying AD progression and
clinical symptoms appear . Therefore, there has been a in seeking for curative treatment.
[1]
growing interest in subjective cognitive decline (SCD) and AD is now regarded as a continuum progressing from
mild cognitive impairment (MCI), which are both regarded unnoticeable brain alterations to subsequent memory
as the preclinical and prodromal stages of AD , in recent impairments that are caused by brain alterations and
[2]
years. Compared to MCI, in which irreversible neuronal eventually physical disability . Considering the disease as
[11]
damage has been observed , SCD receives more research multifactorial and multidirectional (i.e., neuron, structure,
[3]
interest for the reason that cognitive functioning is still and function), it has been recommended that a spectrum
relatively preserved through compensation or restitution may be more suitable than categorical subtypes .
[6]
of function at this stage, and patients could potentially A preliminary screening and monitoring tool that can be
benefit from timely interventions . used in coordination with the current AD guideline to
[4]
However, we find that individual differences, assist in identifying patients who are likely to be overlooked
which play a crucial role in disease progression, have and at a greater risk for disease progression is essential.
rarely been emphasized in the current diagnostic or We, therefore, propose the Brief Risk Rating Scale (BRRS),
therapeutic guideline. Research has suggested that not which allows the quantification of individual risk factors
[5]
all AD-spectrum patients have structural atrophy or and existing brain alterations, so as to make full use of
memory impairment . A variation in brain organization, individual information for the sake of a better assessment
[6]
the differences in regional vulnerability, and the pathologic of individual’s risk level, the prediction and tracking of
diversity potentially result in complex AD subtypes . disease progression, as well as a precise treatment in a
[7]
Throughout the prolonged course of the disease, different timely manner. In parallel with the continuous efforts in
AD subtypes may exhibit different progressing patterns discovering the underlying pathological mechanisms,
that are inconsistent with the developing order observed developing advanced diagnostic technology, and designing
in the guideline . Besides, the previous studies have new pharmacological approaches, BRRS provides an
[5]
suggested that AD is heterogeneous not only in terms of economical, efficient, and accessible way to make progress
its clinical manifestations at diagnosis but also with regard in achieving the goal of preventing, stopping, and curing
to the rate of disease progression . Consequently, there AD [12,13] .
[8]
are several limitations in the current diagnostic criteria
for a comprehensive evaluation, including the etiology, 2. Methods
pattern and speed of progression, as well as the degree of A recent systematic review and meta-analysis of AD risk
[14]
deterioration. Our investigation finds that only a number factors and interventions has proposed 21 evidence-based
of studies took both stages and subtypes of AD patients into suggestions with different levels of evidence (11 with Level
account when designing the group, whereas most studies A and 10 with Level B) and strengths of suggestions (19
considered either of them, of which the results obtained with Class I and two with Class III) on AD prevention.
represented the mean characteristic of AD in a normal It is hitherto the most comprehensive and large-scale
distribution. Nonetheless, it is in essence more likely to be systematic review and meta-analysis, which included a
a skewed distribution due to individual variation among total of 243 observational prospective studies and 153
patients. randomized controlled trials, to evaluate AD risk factors
In addition, despite a significant amount of time and and offer clinicians and stakeholders credible guidance for
financial expenses invested, effective methods to cure AD AD prevention. Hence, the first part of BRRS concerning
remain undiscovered to date; instead, they merely serve to individual’s risk level was formulated primarily on the
alleviate clinical symptoms or potentially slow the disease basis of this excellent review.
progression to some extent . Therefore, conservative With regard to the second part, which focuses on
[9]
medicine or therapies are predominantly used . the aberrant structural and functional brain alterations
[10]
However, such standardized treatment fails to deal with of AD-spectrum patients, PubMed and Web of Science
the differences in clinical features among AD patients; for databases were searched for related articles, published
example, the degree of severity and urgency. Under these from January 2000 to December 2021. Keyword searches
circumstances, patients over the mean value are at high were conducted using the following search terms: ([SCD
risk of being overlooked, thus missing the optimal time (Title/Abstract)] OR [subjective cognitive impairment
window for early intervention, which not only leads to (Title/Abstract)] OR [MCI (Title/Abstract)] OR [AD
reduced diagnostic accuracy and therapeutic effectiveness (Title/Abstract)]) AND (AD [Title/Abstract]) AND
but also blocks the progress in the discovery of the ([magnetic resonance imaging (MRI)] OR [structural

Volume 1 Issue 3 (2022) 2 https://doi.org/10.36922/an.v1i3.208