Unveiling distinct clinical manifestations of primary familial brain calcifications in Asian and European patients: A study based on 10-year individual-level data

Background: Primary Familial Brain Calcification (PFBC) can manifest clinically with a complex and heterogeneous array of symptoms, including parkinsonism, dysarthria, and cognitive impairment. However, the distinct presentations of PFBC in Asian and European populations remain unclear. Methods: We conducted a systematic search of PubMed for studies involving genetically confirmed PFBC patients. Demographic data, genetic information, radiological examinations, and clinical characteristics were extracted for each case. Results: The study included 120 publications and 564 genetically confirmed PFBC patients. Asian and European PFBC populations represented 54 % and 37 % of global patients, respectively. While calcification patterns showed no significant differences between Asian and European PFBC patients, European autosomal dominant PFBC variant carriers were more likely to exhibit clinical symptoms compared to their Asian counterparts (OR = 2.90, 95 % CI 1.55-5.60) and had an earlier estimated age of onset (median age 42 vs 58). Conclusion: The interaction between regional differences and genetically determined calcification severity may collectively influence PFBC symptom progression. Future research should further explore the potential roles of gene modifiers, ethnic background, socioeconomic and environmental exposure factors underlying regional differences in PFBC progression.