The prevalence of frontotemporal dementia: a systematic review and meta-analysis.

BACKGROUND: Frontotemporal dementia (FTD) is a leading cause of early-onset dementia in individuals under 65. Despite its significant burden, a comprehensive synthesis of its global prevalence is lacking. We conducted a systematic review and meta-analysis to estimate the worldwide prevalence of FTD. METHODS: We systematically searched multiple databases for epidemiological studies on FTD prevalence published up to October 31, 2025. Meta-analysis was performed using a random-effects model. Subgroup analyses were conducted by geographic region, age range, and diagnostic criteria era. We systematically searched multiple databases for epidemiological studies on FTD prevalence published up to October 31, 2025. Meta-analysis was performed using a random-effects model. Subgroup analyses were conducted by geographic region, age range, and diagnostic criteria era. RESULTS: A total of 21 studies, encompassing 38,656, 516 individuals, were included. The pooled global prevalence of FTD was 30 cases per 100,000 population (0.03%, 95% CI: 0.01% to 0.12%), with extreme heterogeneity (I² = 100%). Subgroup analyses revealed associations between prevalence and age range (P=0.01), but not by region (P=0.38) or diagnostic criteria era (P=0.28). Visual inspection of the funnel plot suggested asymmetry, though Egger's test showed no significant small-study effects (P = 0.254). CONCLUSION: The reported prevalence varied widely across studies. Although the overall estimated prevalence is relatively low, the substantial variability and study limitations warrant cautious interpretation. This study provides a benchmark estimate for global FTD prevalence and underscores the urgent need for more high-quality, population-based epidemiological studies, particularly in underrepresented regions like China, to guide effective public health strategies.