The detailed longitudinal study of Godbolt et al1 is an important contribution to our knowledge of the early onset and course of Alzheimer disease (AD). However, several of the findings and conclusions bear further analysis.
The authors point out that survival from the onset of symptoms “ . . . compares favorably with that in later-onset sporadic AD.” With several reasonable estimates of life expectancy for those in residential care and for the 10 patients with AD living at home, one can calculate a weighted mean time from symptomatic onset to death for this cohort of some 8.5 to 11 years, supporting the authors' observation.
Lesser GT. Survival in Alzheimer Disease. Arch Neurol. 2005;62(4):689. doi:10.1001/archneur.62.4.689-a