Durjoy Lahiri, MD, DM
Division of Neurology, Department of Medicine, Queen’s University, Kingston, ON
To the Editor,
I read with great interest the commentary by Montero-Odasso, Lee, and Hogan regarding the resource challenges facing Canadian brain health care in the present times.(1) The authors rightly argue that it should be more than solely deciding on who can receive amyloid targeting treatments. While the need for a holistic approach towards improving brain health is deeply appreciated, at least part of the argument seems to have a problematic premise that these therapies are a niche intervention relevant to too small a fraction of patients. By citing restrictive “real-world eligibility” figures of 6–8%, the authors inadvertently rely on a denominator illusion that mischaracterizes clinical utility.
The 6–8% figure represents all unselected patients entering a general memory clinic, including those with advanced dementia or even non-Alzheimer’s pathologies. When the analytical lens is adjusted to the true target population of early Alzheimer’s disease (AD)—as seen from both European tertiary clinics(2) and population-based cohorts like the Mayo Clinic Study of Aging(3)—eligibility climbs to 15–21% of patients strictly in the early stages of AD (mild cognitive impairment or mild dementia) who lack major safety contraindications. A therapy that could alter the disease trajectory for nearly one in five early-stage patients represents a substantial clinical cohort, particularly with analyses showing clinically meaningful effects on cognition and function.(4) These figures should also account for delays in specialist assessment, which allow a proportion of patients to already progress beyond eligibility criteria even before evaluation, leading to an underestimation of the actual eligibility numbers.
In this context, one can draw a curious analogy with the revolutionization of ischemic stroke therapy by the advent of intravenous (IV) thrombolysis, more than two decades ago. It may be more than a mere coincidence that contemporary registry analyses suggest eligibility is approximately 5–10% of all ischemic stroke presentations.(5) Modern workflow improvements, including the implementation of stroke codes, have increased the treated proportion in some stroke systems to >10%, but that does not mean the overall eligible proportion of all ischemic stroke patients has become much higher than earlier even after a long experience with this modern treatment. Yet, in the modern day, it is next to impossible to imagine a higher neurology centre without access to IV thrombolysis.
In this reader’s opinion, one way to timely capture early AD patients is through a streamlined, fast-track pathway embedded within our existing system. By arming primary care providers with rapid screening tools, including plasma p-tau 217 in the right clinical context,(6) patients demonstrating early cognitive impairment can bypass traditional, lengthy waitlists and flow directly into a streamlined diagnostic triage protocol to confirm amyloid status. This targeted workflow rapidly filters out ineligible individuals at the frontline, ensuring that only select candidates reach tertiary specialists for final infusion clearance, while the others continue to receive the traditional and preventative care that the authors have quite expertly outlined. Such a pathway, once established, can function for other future disease-modifying treatments in AD that may well be approved in the coming years.
We can better optimize brain health delivery by integrating therapeutic modernization within the existing framework of care. To keep our eye on the main prize, Canada must build a system capable of both multi-domain lifestyle prevention and cutting-edge molecular care in AD as we enter the “golden age of Alzheimer’s research”(7).
Not applicable.
We have read and understood the Canadian Geriatrics Journal’s policy on conflicts of interest disclosure and declare that we have none.
Not applicable.
1. Montero-Odasso M, Lee L, Hogan DB. Improving the delivery of brain health care to all. Keeping our eye on the main prize in an era of emerging anti-amyloid therapies. Can Geriatr J. 2026;29(2):144–6. doi: 10.5770/cgj.29.941
PubMed PMC
2. Vigneswaran S, Vijverberg EGB, Barkhof F, van de Giessen E, Lemstra AW, Pijnenburg Y, et al. “Real-world” eligibility for anti-amyloid treatment in a tertiary memory clinic setting. Alzheimers Dement. 2025;21(6):e70375. doi: 10.1002/alz.70375
Crossref
3. Pittock RR, Aakre JA, Castillo AM, Ramanan VK, Kremers WK, Jack CR Jr, et al. Eligibility for anti-amyloid treatment in a population-based study of cognitive aging. Neurology. 2023;101(19):e1837–49. doi: 10.1212/WNL.0000000000207770
Crossref PubMed PMC
4. Atri A, Apostolova LG, Iwata A, Wessels AM, Atkins A, Lu M, et al. Clinical meaningfulness of donanemab in early symptomatic Alzheimer disease: data from the randomized phase 3 TRAILBLAZER-ALZ 2 Trial. Neur Clin Pract. 2026;16(3):e200621. doi: 10.1212/CPJ.0000000000200621
Crossref
5. Mac Grory B, Xian Y, Solomon NC, Matsouaka RA, Decker-Palmer MR, Fonarow GC, et al. Exploring the unmet need in acute ischemic stroke patients not treated with intravenous alteplase: the get with the guidelines-Stroke Registry. Stroke Vasc Interv Neurol. 2022;2(1):e000226. doi: 10.1161/SVIN.121.000226
Crossref
6. Lahiri D, Cooper JG, Seixas-Lima B, Roncero C, Wellington CL, Chertkow H. CAPS Plus: a clinical biomarker scoring system to predict Aβ positivity and facilitate enrolment in anti-amyloid clinical trials. Can J Neurol Sci. Published online January 20, 2026:1–22. doi: 10.1017/cjn.2026.10530
Crossref
7. Gates B. We’re entering a golden age of Alzheimer’s research. Gates Notes. Published online June 2, 2026. Available from: https://www.gatesnotes.com/entering-a-golden-age-of-alzheimers-research
COPYRIGHT
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial No-Derivative license (https://creativecommons.org/licenses/by-nc-nd/4.0/), which permits unrestricted non-commercial use and distribution, provided the original work is properly cited.
Canadian Geriatrics Journal, Vol. 29, No. 3, SEPTEMBER 2026