Incidence and Prevalence of Frontotemporal Dementia Similar to Dementia with Lewy Bodies, Meta-Analysis Shows

A population-based systematic review and meta-analysis published in JAMA Journal reviewed previous studies on the incidence and perveance of frontotemporal dementia (FTD) and found that FTD is comparable in frequency to dementia with Lewy bodies (DLB) and occurs at higher rates then progressive supranuclear palsy, corticobasal syndrome, and amyotrophic lateral sclerosis (ALS).¹

The analysis comprised 32 studies, 16 on perveance and 22 on incidence reporting FTD measures, aiming to estimate the incidence and prevalence of incident and prevalent FTD cases using random-effects meta-analysis. Eligible studies used validated diagnostic criteria such as frameworks from the Lund and Manchester Groups or reported FTD diagnoses using Diagnostic and Statistical Manual of Mental Disorders (DSM) or International Classification of Diseases (ICD) classifications.

When pooling data, the crude incidence of FTD was 2.28 (95% CI, 1.55-3.36) per 100,000 person-years while it was prevalent in 9.17 (95% CI, 3.59-23.42) per 100,000 people. All told, the behavioral-variant FTD pooled crude incidence was 1.20 (95% CI, 0.67-2.16) per 100,000 person-years and prevalence, 9.74 (95% CI, 2.90-32.73) per 100,000 people. In comparison, the primary progressive aphasia variant pooled crude incidence was 0.52 (95% CI, 0.35-0.79) per 100,000 person-years and prevalence, 3.67 (95% CI, 3.05-4.43).

Led by Daniele Urso, MD, MPH, a consultant neurologist and researcher for the Center for Neurodegenerative Diseases and Aging Brian in Tricase, Italy, the systematic review analyzed a population of approximately 31 million person-years for incidence and 6 million individuals for prevalence spread across 12 different regions around the world. The denominator based on census data showed less heterogeneity than the population at risk defined by the authors (I²: for incidence, 91.6% vs 97.6%, respectively, and for prevalence, 98.8% vs 99.2%, respectively).

READ MORE: Anti-MTBR Tau Antibody Etalanetug Given FDA Fast Track Designation

The authors of the study noted the importance of establishing reliable data on the disorder writing that, “Identifying the incidence and prevalence of FTD remains essential to guide clinical research, health service organization, and specialized care delivery. Although FTD is a rare disorder, reliable epidemiological estimates are crucial to optimize access to diagnostic expertise, support the development of specialized clinical services, and design targeted interventions.”¹

The articles included in the study were drawn from PubMed, EMBASE, and Scopus between January 1, 1990, and October 22, 2024, and were extracted independently by 2 investigators in accordance with PRISMA guidelines. Additionally, the study found the pooled incidence rate of FTD in populations younger than 65 years was 1.84 cases per 100 000 person-years (95% CI, 0.79-4.30) and prevalence rates in populations younger than 65 years were lower, with a pooled prevalence of 7.47 cases per 100 000 population (95% CI, 4.13-13.49).

The authors highlighted the significance of accurate epidemiological data in advancing treatment research, writing that, “the increasing understanding of FTD’s complex pathophysiology, involving molecular subtypes such as FTLD-tau and FTLD with TDP-43 pathology, highlights the importance of precise data to support advancements in both pharmacological and nonpharmacological treatments. Given the growing pipeline of disease-modifying therapies targeting tau, TDP-43, and genetic mutations like C9orf72 and GRN, accurate epidemiological data are crucial for the design and evaluation of clinical trials.”¹

The authors acknowledged several limitations in the study including the considerable variation between studies which reflects the complexity of combining data on a rare and clinically diverse disorder such as FTD. Additionally, Regional genetic differences and potential environmental or modifiable risk factors, which remain less well characterized for FTD than for Alzheimer’s disease, may also contribute to the observed variability. Furthermore, the analysis included studies primarily from Europe, the United States, and Japan, which may limit the applicability of the findings to other regions. The authors noted that future studies should aim to include more geographically and demographically diverse populations and provide age- and sex-specific data to enhance comparability.

REFERANCES
1. Urso D, Giannoni-Luza S, Brayne C, Ray N, Logroscino G. Incidence and Prevalence of Frontotemporal Dementia: A Systematic Review and Meta-Analysis. JAMA Neurol. Published online September 08, 2025. doi:10.1001/jamaneurol.2025.3307