Prevalence of transactive response DNA‐binding protein 43 (TDP‐43) proteinopathy in cognitively normal older adults: systematic review and meta‐analysis

ObjectiveTo perform a systematic review and meta-analysis on the prevalence of transactive response DNA-binding protein 43 (TDP-43) proteinopathy in cognitively normal older adults.MethodsWe systematically reviewed and performed a meta-analysis on the prevalence of TDP-43 proteinopathy in older adults with normal cognition, evaluated by the Mini-Mental State Examination or the Clinical Dementia Rating. We estimated the overall prevalence of TDP-43 using random-effect models, and stratified by age, sex, sample size, study quality, antibody used to assess TDP-43 aggregates, analysed brain regions, Braak stage, Consortium to Establish a Registry for Alzheimer's Disease score, hippocampal sclerosis and geographic location.ResultsA total of 505 articles were identified in the systematic review, and 7 were included in the meta-analysis with 1196 cognitively normal older adults. We found an overall prevalence of TDP-43 proteinopathy of 24%. Prevalence of TDP-43 proteinopathy varied widely across geographic location (North America: 37%, Asia: 29%, Europe: 14%, and Latin America: 11%). Estimated prevalence of TDP-43 proteinopathy also varied according to study quality (quality score >7: 22% vs. quality score <7: 42%), antibody used to assess TDP-43 proteinopathy (native: 18% vs. hyperphosphorylated: 24%) and presence of hippocampal sclerosis (without 24% vs. with hippocampal sclerosis: 48%). Other stratified analyses by age, sex, analysed brain regions, sample size and severity of AD neuropathology showed similar pooled TDP-43 prevalence.ConclusionsDifferent methodology to access TDP-43, and also differences in lifestyle and genetic factors across different populations could explain our results. Standardization of TDP-43 measurement, and future studies about the impact of genetic and lifestyle characteristics on the development of neurodegenerative diseases are needed

Erratum.

The publisher apologizes for erroneously omitting part of the footnote for Table 2. This has now been corrected both online and in print