title: Survival in Frontotemporal Dementia Phenotypes: A Meta-Analysis.
abstract: BACKGROUND
  Survival in frontotemporal dementia (FTD) is not well understood. We conducted a mixed effects meta-analysis of survival in FTD to examine phenotype differences and contributory factors.
  
  
  METHODS
  The PubMed, Medline, EMBASE, CINAHL, PsycINFO and Cochrane databases were searched for studies describing survival or natural history of behavioral variant FTD (bvFTD), progressive non-fluent aphasia (PNFA), semantic dementia (SD), FTD with amyotrophic lateral sclerosis (FTD-ALS), progressive supranuclear palsy and corticobasal degeneration. There were no language restrictions.
  
  
  RESULTS
  We included 27 studies (2,462 subjects). Aggregate mean and median survival were derived for each phenotype and, for comparison, Alzheimer's disease (AD) (using data from the selected studies). Survival was shortest in FTD-ALS (2.5 years). Mean survival was longest in bvFTD and PNFA (8 years) and median survival in SD (12 years). AD was comparable in survival to all except FTD-ALS. Age and sex did not affect survival; the education effect was equivocal. Heterogeneity in FTD survival was largely, but not wholly, explained by phenotypes.
  
  
  CONCLUSIONS
  Survival differs for FTD phenotypes but, except for FTD-ALS, compares well to AD survival. Elucidating the potential causes of within-phenotype heterogeneity in survival (such as complicating features and comorbidities) may open up opportunities for tailored interventions.
authors: Division of Geriatric Psychiatry and Neuropsychiatry, Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Md., USA.
authors: Kalyani
authors: K
authors: Kansal
authors: Manisha
authors: M
authors: Mareddy
authors: Kelly L
authors: KL
authors: Sloane
authors: Alexa A
authors: AA
authors: Minc
authors: Peter V
authors: PV
authors: Rabins
authors: John B
authors: JB
authors: McGready
authors: Chiadi U
authors: CU
authors: Onyike
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000401:mortality*; D000690:Amyotrophic Lateral Sclerosis / Q000401:mortality; D005260:Female; D057180:Frontotemporal Dementia / Q000401:mortality*; D006801:Humans; D008297:Male; D010641:Phenotype; D057178:Primary Progressive Nonfluent Aphasia / Q000401:mortality; D013494:Supranuclear Palsy, Progressive / Q000401:mortality; D015996:Survival Rate