[Initial symptoms, survival and causes of death in 115 patients with frontotemporal lobar degeneration].

The early and differential diagnosis of the clinical phenotypes of frontotemporal lobar degeneration (FTLD), including frontotemporal dementia (FTD), semantic dementia (SD) and non-fluent progressive aphasia (NFPA), can be challenging. It may be difficult not only to differentiate these conditions from normal aging, psychiatric disorders, and other dementias, but also to distinguish between them. For early diagnosis, information on the initial and presenting symptoms of the FTLD phenotypes is essential. In the present study caregivers of 78 patients with FTD, 20 patients with SD and 17 patients with PA were interviewed about initial symptoms. In patients with FTD, the most frequent initial symptoms were alterations of personality, followed by forgetfulness and word finding difficulty. Patients with SD presented with word finding difficulty and behavioral disturbances. Almost all patients with PA developed word finding difficulty as the first manifestation of their disorder. Diagnostic latency - the time from disease onset to diagnosis was 4.1 years in FTD, 4.2 years in SD and 3.1 years in PA. Caregivers, and in some cases also patients, should be educated about the likely course and mortality of FTLD. To obtain information about survival time and cause of death associated with FTLD we analyzed follow-up data on 106 patients of whom 25 had died. The median survival time from the occurrence of first symptoms was 14 years. Mortality risk was significantly higher in patients with an early disease onset. Causes of death were varied, but pneumonia and sudden unexplained deaths were particularly frequent.