Highlights
- Average time to dementia diagnosis (TTD) is 3.5 years after symptom onset.
- Younger onset and frontotemporal dementia are associated with even longer diagnostic delays.
- Delays are driven by clinical, social, and healthcare system barriers.
- Timely diagnosis remains a critical unmet need for patients and families.
Study Background and Disease Burden
Dementia is a progressive neurodegenerative condition affecting over 55 million people worldwide and is a leading cause of disability in older adults. Early diagnosis is pivotal for optimal care, timely intervention, and effective support for patients and caregivers. Despite global awareness campaigns and advances in diagnostic criteria, many individuals and families experience protracted and distressing delays between the initial onset of cognitive symptoms and a formal dementia diagnosis. Understanding the magnitude and drivers of these diagnostic delays has critical implications for clinical practice, health policy, and research prioritization.
Study Design
This timely systematic review and meta-analysis by Kusoro et al. (Int J Geriatr Psychiatry, 2025) synthesized data from 13 cohort studies published up to December 2024. Over 30,000 adults with a confirmed diagnosis of dementia were included, with age at symptom onset ranging from 54 to 93 years. The primary outcome, time to diagnosis (TTD), was defined as the interval between symptom onset (as reported by patients or family carers, or extracted from medical records) and the formal clinical diagnosis of dementia. The analysis examined TTD across all dementias, by age of onset (young-onset vs. late-onset), and by dementia subtype (notably Alzheimer’s disease and frontotemporal dementia).
Key Findings
The meta-analysis provides robust, moderate-quality evidence regarding diagnostic delays in dementia:
- Overall TTD: Across 10 studies, the mean TTD was 3.5 years (95% CI, 2.7–4.3), indicating a substantial lag between symptom recognition and diagnosis.
- Young-Onset Dementia: In six studies, patients with young-onset dementia (onset before age 65) experienced an average TTD of 4.1 years (95% CI, 3.4–4.9), longer than in the general dementia population.
- Dementia Subtypes: The analysis highlighted pronounced delays for certain subtypes:
- Young-onset Alzheimer’s disease: mean TTD 4.0 years (95% CI, 2.7–5.2)
- Frontotemporal dementia: mean TTD 4.7 years (95% CI, 3.0–6.4)
- Late-onset dementia (onset after age 65): mean TTD 2.9 years (95% CI, 2.6–3.2; based on two studies)
These findings imply that diagnostic delays are not only prevalent but are worst for individuals with early-onset or non-Alzheimer’s dementias, which often present with atypical symptoms and are less recognized by both the public and clinicians.
Expert Commentary
Dr. Victoria Orgeta, co-author of the study, emphasizes the need for a clearer conceptual framework for TTD, developed in partnership with patients, families, and professionals. She notes that diagnostic delays have profound consequences for care planning and patient autonomy.
Dr. Phuong Leung (UCL Division of Psychiatry) highlights the challenges of symptom misattribution—dementia’s early signs are often mistaken for normal aging. Stigma, fear, and low awareness further discourage help-seeking behavior.
Professor Rafael Del-Pino-Casado (University of Jaén) points to systemic healthcare barriers: inconsistent referral pathways, insufficient access to dementia specialists, and under-resourced memory clinics. Additional obstacles include language barriers and the lack of culturally sensitive assessment tools, particularly in diverse or underserved populations.
These expert perspectives underscore that diagnostic delay in dementia is multifactorial, involving patient-level, family-level, and system-level challenges. Addressing these will require a coordinated, interdisciplinary effort.
Conclusion
This meta-analysis quantifies a persistent and clinically significant gap in dementia care: the average person waits 3.5 years from symptom onset to diagnosis, with even longer delays in younger individuals and those with frontotemporal dementia. The findings highlight urgent gaps in public awareness, clinician education, and healthcare infrastructure. Timely diagnosis is essential for optimal patient outcomes, family support, and health system efficiency. Future research should focus on interventions to shorten TTD, including public health campaigns, streamlined referral pathways, and improved access to specialist assessment. Collaboration between clinicians, patients, carers, and policymakers will be key to reducing the diagnostic burden of dementia.
References
1. Kusoro O, Roche M, Del-Pino-Casado R, Leung P, Orgeta V. Time to Diagnosis in Dementia: A Systematic Review With Meta-Analysis. Int J Geriatr Psychiatry. 2025 Jul;40(7):e70129. doi: 10.1002/gps.70129. PMID: 40716451; PMCID: PMC12300619.
2. Dementia takes 3.5 years to diagnose after symptoms begin. https://www.eurekalert.org/news-releases/1092392