Predictors of mortality in frontotemporal dementia: a retrospective study of the prognostic influence of pre‐diagnostic features

OBJECTIVES: To find associations between predictors and survival in frontotemporal dementia (FTD). METHODS: 96 patients with FTD, here defined as Dementia in Pick's disease, were studied. The predictors included psychiatric/behavioural features, language impairment and neurological deficits present up to the time of diagnosis. The influence on mortality was studied by means of Cox regression analyses. RESULTS: Most of the behavioural/psychiatric features were associated with longer survival. Among these features, anxiety and suicidal ideation were associated with a statistically significant decreased mortality. Semi-mutism/mutism and neurological deficits were associated with a statistically significant increased mortality. Analyses of the dementia-specific mortality strengthened the already significant results and revealed dysphagia as significantly related to increased mortality. CONCLUSIONS: Two groups of predictors with different influence on survival were identified in FTD. Most behavioural/psychiatric features were associated with longer survival. These features may indicate a slower disease progress and a better preserved cerebral function. By contrast, semi-mutism/mutism, neurological deficits and dysphagia were associated with shorter survival, indicating an aggressive, degenerative process.