History, Present, and Progress of Frontotemporal Dementia in China: A Systematic Review

We aim to provide an overview of clinical and demographical features and neuropathological research on frontotemporal dementia (FTD) from China over the past decade. We reviewed the demographic features, clinical presentations, and neuropathology of the FTD-spectrum disorders from the 49 cases in China published since 1998. On the basis of these findings, we retrospect the history and speculate on future progress in terms of FTD in China. We found that most published papers comprise case reports with a few retrospective studies with small sample sizes. Behavior variant FTD (bvFTD) was the most common diagnostic subtype, of which 35% were associated with amyotrophic lateral sclerosis or Parkinsonian syndrome. More than 47% patients with FTD had age onset before 65. There were no differences in age of onset and sex distribution between diagnostic subtypes. The spectrum of neuropathological diagnosis of bvFTD was frontotemporal lobe degeneration (FTLD) with tau protein or ubiquitin-immunopositive inclusions, and FTLD without intracellular inclusions. Median survival in bvFTD was 14 years. This paper provides an overview of the current status and pointers for future research directions of FTD in China.