Background: Alzheimer’s disease (AD) is a neurodegenerative disorder that is characterized
by a progressive deterioration of various cognitive, social and functional abilities. It has been reported
that the clinical feature of AD may differ according to the onset of age the disease. Therefore,
the aim of this study was to compare instrumental activities of daily living (IADL) in earlyonset
AD (EOAD) and late-onset AD (LOAD). Methods: The patients diagnosed as AD between
November 2005 and December 2008 were included in the study. Subjects consisted of 356
patients and were divided into EOAD and LOAD based on the onset age of 65 yr. We assessed
their demographics and examined the Mini Mental State Examination (MMSE), Geriatric Depression
Scale (GDS), Clinical Dementia Rating (CDR), and Seoul-instrument activities of daily living
(S-IADL). We defined CDR 0.5 and 1 as mild and 2 as moderate severity of dementia. Results:
Out of the 356 patients, 128 (36%) were EOAD and 228 (64%) were LOAD. EOAD patients demonstrated
significantly greater impairment of IADL than LOAD when gender, level of education,
CDR, level of depression, and duration of dementia were controlled (p<0.001). In mild severity
of dementia, the total S-IADL score was not significantly different between the two groups
(p=0.753). However, EOAD patients showed greater impairment of IADL than LOAD on 3 items
(managing belongings, grooming, unlock and close entrance door, keeping appointment; p=
0.014, p=0.004, p=0.039, p=0.022, respectively), while LOAD showed greater impairment in
preparing food and cooking than EOAD (p=0.003). In moderate severity of dementia, EOAD
patients showed significantly greater impairment of IADL than LOAD (p=0.039) and greater
impairment in unlock and close entrance door and talking recent events than LOAD (p=0.014,
p=0.049, respectively). The IADL performance was significantly associated with cognitive function,
duration of dementia, and level of education in EOAD, whereas in LOAD, it was significantly
associated with cognitive function. Conclusions: Our study suggests that EOAD patients generally
manifest greater impairment of IADL than LOAD and the MMSE may be strongly correlated
with the IADL.
Background: Alzheimer’s disease (AD) is a neurodegenerative disorder that is characterized
by a progressive deterioration of various cognitive, social and functional abilities. It has been reported
that the clinical feature of AD may differ according to the onset of age the disease. Therefore,
the aim of this study was to compare instrumental activities of daily living (IADL) in earlyonset
AD (EOAD) and late-onset AD (LOAD). Methods: The patients diagnosed as AD between
November 2005 and December 2008 were included in the study. Subjects consisted of 356
patients and were divided into EOAD and LOAD based on the onset age of 65 yr. We assessed
their demographics and examined the Mini Mental State Examination (MMSE), Geriatric Depression
Scale (GDS), Clinical Dementia Rating (CDR), and Seoul-instrument activities of daily living
(S-IADL). We defined CDR 0.5 and 1 as mild and 2 as moderate severity of dementia. Results:
Out of the 356 patients, 128 (36%) were EOAD and 228 (64%) were LOAD. EOAD patients demonstrated
significantly greater impairment of IADL than LOAD when gender, level of education,
CDR, level of depression, and duration of dementia were controlled (p<0.001). In mild severity
of dementia, the total S-IADL score was not significantly different between the two groups
(p=0.753). However, EOAD patients showed greater impairment of IADL than LOAD on 3 items
(managing belongings, grooming, unlock and close entrance door, keeping appointment; p=
0.014, p=0.004, p=0.039, p=0.022, respectively), while LOAD showed greater impairment in
preparing food and cooking than EOAD (p=0.003). In moderate severity of dementia, EOAD
patients showed significantly greater impairment of IADL than LOAD (p=0.039) and greater
impairment in unlock and close entrance door and talking recent events than LOAD (p=0.014,
p=0.049, respectively). The IADL performance was significantly associated with cognitive function,
duration of dementia, and level of education in EOAD, whereas in LOAD, it was significantly
associated with cognitive function. Conclusions: Our study suggests that EOAD patients generally
manifest greater impairment of IADL than LOAD and the MMSE may be strongly correlated
with the IADL.