K. Fahlander et al., Depression does not aggravate the episodic memory deficits associated withAlzheimer's disease, NEUROPSYCHL, 13(4), 1999, pp. 532-538
In a population-based study of persons between 75 and 96 years of age, norm
al old adults (n = 296), patients with Alzheimer's disease (AD; n = 45), an
d patients with concomitant AD and depression (AD-D; n = 9) were compared o
n free recall and recognition of slowly and rapidly presented words and dig
it span. With the exception of forward digit span, the normal old group out
performed the 2 AD groups across all tasks. In free recall, only the normal
old group performed better as task pacing decreased; however, all groups b
enefited from more study time in recognition. This suggests that both AD an
d AD-D patients have deficits in the ability to use more study time for rem
embering. Of most importance, the 2 AD groups were indistinguishable for al
l task variables. This lack of comorbidity effects is discussed relative to
the view that depression, much like many other individual-difference varia
bles that affect memory performance in normal aging, may be overshadowed by
the influence of the neurodegenerative process in AD.