Frequency of early and late-onset dementias in a Japanese memory disorders clinic.
The aim of this study was to compare the diagnostic profiles of patients with early (age<65 years) and late (age>or=65 years) onset of dementia in a memory disorders clinic in Japan. A total of 512 consecutive memory clinic patients were evaluated using clinical information and results of examinations. Diagnosis of dementia was made according to DSM-III-R, and that of subtypes according to standard diagnostic criteria. A total of 464 patients met the criteria for dementia. Amongst late-onset patients (n=430), Alzheimer's disease (AD) (48.1%) was the most frequent cause of dementia, followed by AD with cerebrovascular disease (CVD) (31.4%), vascular dementia (VaD) (9.1%), dementia with Lewy bodies (DLB) (3.7%), frontotemporal lobar degeneration (FTLD) (1.6%), and others (5.8%). On the contrary, amongst early onset patients (n=34), the most common dementia diagnosis was AD (38.2%), followed by VaD (23.5%), FTLD (14.7%), AD with CVD (5.9%), DLB (2.9%), and others (17.6%). FTLD and VaD were significantly more common in the early onset group. All patients, but one, with DLB and Parkinson's disease dementia were late-onset. The relative frequencies of AD, VaD, and DLB in our series are consistent with epidemiologic findings in several Western countries; however, the frequency of FTLD is not consistent with the previous findings presenting high frequency in late-onset patients in some Western countries.
Yokota
O
O
Department of Neuropsychiatry, Okayama University Graduate School of Medicine and Dentistry, Okayama, Japan. oyokota1@yahoo.co.jp
Sasaki
K
K
Fujisawa
Y
Y
Takahashi
J
J
Terada
S
S
Ishihara
T
T
Nakashima
H
H
Kugo
A
A
Ata
T
T
Ishizu
H
H
Kuroda
S
S
D000251:Adenosine Triphosphatases; D000328:Adult; D000367:Age Factors; D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D003431:Cross-Cultural Comparison; D004268:DNA-Binding Proteins; D003704:Dementia / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D001523:Mental Disorders / Q000453:epidemiology* / Q000209:etiology*; D008609:Mental Status Schedule / Q000706:statistics & numerical data; D008875:Middle Aged; D014157:Transcription Factors
D004268:DNA-Binding Proteins; D014157:Transcription Factors; D000251:Adenosine Triphosphatases; C477874:TTF2 protein, human