Objective: The aim of the present study was to determine the accuracy
of clinical diagnoses of dementia in a large group of patients evaluat
ed in a multicenter, university-based, Alzheimer's disease diagnostic
and treatment program. Method: Clinical diagnoses and neuropathologica
l results from seven collaborating Alzheimer's disease research center
s were compared for 196 cases of dementia. Results: When diagnoses of
probable Alzheimer's disease, possible Alzheimer's disease, and Alzhei
mer's disease plus another condition were combined, 163 (83%) of the p
atients were clinically regarded as likely to have had Alzheimer's dis
ease. Of those patients, 134 (82%) were found to have neuropathologica
l changes diagnostic of Alzheimer's disease or Alzheimer's disease plu
s another condition. A total of 116 patients were diagnosed as having
probable Alzheimer's disease; 100 (86%) of those were found to have pa
thological diagnoses of Alzheimer's disease or Alzheimer's disease plu
s another condition. Cerebral infarcts were found in 17% of the patien
ts clinically diagnosed with probable Alzheimer's disease. Lewy bodies
with variable Alzheimer's disease-type pathological changes were foun
d in 7% of the patients with clinical diagnoses of probable Alzheimer'
s disease. Conversely, significant Alzheimer's disease-type pathologic
al changes were found in 55% of the patients clinically diagnosed as h
aving vascular dementia. Conclusions: Clinicians accurately predict Al
zheimer's disease-type neuropathological findings in a high proportion
of cases of dementia but may not predict cerebrovascular pathology an
d Lewy bodies in some patients with apparent clinical Alzheimer's dise
ase and may often fail to predict Alzheimer's disease type pathologica
l findings in patients with apparent vascular dementia. With the emerg
ence of effective treatments for Alzheimer' disease, there is an incre
asing need to optimize methods for ante-mortem diagnosis of dementia.