Is screening for Alzheimer's disease ready for prime time? Ask Wilson and Jungner.

Population screening is an effective strategy for disease prevention, early diagnosis and treatment; however, the benefits and harms of disease screening need to be carefully evaluated before clinical implementation. Various national and international bodies, including the U.S. Preventive Services Task Force (USPSTF), periodically develop recommendations for screening after reviewing the available published evidence and, in some instances, expert opinions. In 1968, Wilson and Jungner formulated a set of 10 rules that must be considered and fulfilled before introducing screening for any disease into clinical practice. Alzheimer's disease (AD), a devastating chronic disease that affects millions of people worldwide and is the most common cause of dementia, has recently been reviewed in the context of population screening. Data and predictions show that the prevalence of AD is steadily increasing and will likely become one of the most common causes of death by 2060. Currently, there are no effective curative therapeutic options for this disease, but new developments have allowed earlier detection at asymptomatic and early symptomatic stages. New classes of disease-modifying therapeutics show promise of slowing the progression of the disease. These new developments prompted us to examine the near-future feasibility of screening for presymptomatic or early symptomatic AD by considering the general screening principles of Wilson and Jungner. In 2020, USPSTF published a guideline regarding screening for cognitive impairment, an AD symptom, and concluded that the current evidence is insufficient to assess the balance of benefits and harms and did not recommend screening for cognitive impairment in older adults. This was recapitulated in 2024 by the Canadian Task Force on Preventive Health Care (CTFPHC). After careful consideration, and despite the recent significant biological, diagnostic and therapeutic advances for AD, screening does not seem to be justified at present, due to numerous reasons, such as lack of trained professionals and specialized clinics to handle the anticipated highly increased workload, the huge cost, the ineffectiveness and side effects of current therapy, the lack of long-term therapy studies, and the disagreement among experts as to whom to test and treat and when (at either asymptomatic or early symptomatic stages).