Pmg. N-Psychophannacd
& Brol Psychu
printed in Orcat Brttatn. AU rl&ts
0278 -S&16/93
1993. Vol. 17. pp. 775-779
8 1993 Pergamon
mewed
$24.00
Press Ltd
THE RELATIONSHIP OF CLINICAL
PSYCHOPATHOLOGIC RATING AND COGNITIVE
FACTORS TO CLINICAL DEMENTIA STAGING
JOHN S. KENNEDY1*3p4*5,MILTON E. STRAUSS2*4,
KATHLEEN A. SMYTH3*4 AND PILFER J. WI-IITEH~USE~*~
‘Department of Psychiatry, *Department of Psychology,
3Alzheimer’s Center, University Hospitals of Cleveland and
4Case Western Reserve University, Cleveland, Ohio, USA
(Final Form, November 1992)
Kennedy, John S., Milton E. Strauss, Kathleen A. Smyth and Peter J. Whitehouse: The Relationship
of Clinical Psychopathologic Rating and Cognitive Factors to Clinical Dementia Staging. Prog.
Neuro-Psychopharmacol. & Biol. Psychiat. 1993, .17(5): 775-779.
1.
2.
3.
4.
Sixty-six patients were assessed by one of three physicians employing CERAD assessment and
were staged by CDR criteria.
The same day, trained raters completed the Brief Psychiatric Rating Scale, the Cornell Scale
for Depression in Dementia and the Mini-mental State Examination.
Clinician’s Global Rating of the CDR is strongly related to the Mini-mental State Examination
Score.
The CDR is insensitive to mild psychopathology in this population.
Keywords: CERAD, Clinical Dementia Rating Scale, Probable Alzheimer’s Disease,
Psychopathology.
Abbreviations:
Alzheimer’s Disease (AD), Brief Psychiatric Rating Scale (BPRS), Clinical
Dementia Rating Scale (CDR), Consortium to Establish a Registry for Alzheimer’s Disease
(CERAD), Cornell Scale for Depression in Dementia (CSDD), Mini-mental State Exam (MMSE).
Alzheimer’s disease (A.D.) is a degenerative neuropsychiatric disorder characterized by
progressive decline in memory ability and other cognitive functions often accompanied by
psychopathologic features such as psychosis, mood disturbance and personality change. Additionally,
A.D. is characterized by a progressive decline in the individual’s ability to function independently.
‘Present Address: Department of Psychiatry, Vanderbilt University Medical Center, Nashville, TN, USA
775
J. S. Kennedy et al.
776
Adequately staging the A.D. patient’s current state at differing times during the disorder’s progression
is essential to clinical-pathologic correlational studies and also to determining if proposed therapies alter
the natural history of the disorder.
The Washington University Clinical Dementia Rating Scale (CDR)
(Hughes et al. 1982), commonly used for dementia staging explicitly considers only cognitive
functioning and activities of daily living.
However, it is not clear whether clinicians’ global ratings of
dementia severity are affected by the presence of concurrent psychopathology.
To examine this
question, the authors studied the relationship of physician’s staging of A.D. to independent evaluations
of psychopathology and cognitive state.
Methods
Sixty-six patients who were members of the Alxheimer’s Disease Research Center at University
Hospitals of Cleveland and who fulfilled NINCDS-ADRC criteria for probable Alxheimer’s Disease
(MC Khann et al., 1984) were evaluated by one of three physicians employing the CERAD assessment
protocol (Mirra et al., 1988) and were then staged for dementia severity using CDR criteria.
Independently, on the same day, using all available information from informants as well as direct
interview of the patient, trained raters completed the Brief Psychiatric Rating Scale (BPRS)(Overall &
Gorham, 1962) and the Cornell Scale for Depression in Dementia (CSDD) (Alekopoulos et al., 1988)
and evaluated the A.D. patients cognitive abilities using the Mini-mental State Examination
(MMSE)(Folstein et al., 1975).
Assessment
The CDR scaling was revised so that no dementia was scaled: 1; questionable = 1.5; mild = 2;
moderate = 3; severe = 4. Psychoticism was indexed by the sum of the score on the following BPRS
items which each had the potential range of O-6: conceptual disorganization; suspiciousness;
hallucinatory behavior; unusual thought content. Depression phenomena was indexed by the CSDD total
score with a possible maximum total score of 38. Cognitive ability was indexed by the MMSE score
which has a potential range of O-30. The patient sample is characterized below (Table 1).
Data Analvsis
The data was analyzed by multiple regression of psychoticism, depression and cognitive dimensions on
the dependent variable, CDR dementia stage rating.
’
777
Relation of psychopathology cogniUve factors and dementia stage
Table 1
Description of Sample
MGill
Median
2.2
2.0
.65
1
4
SD
Min
MaX
16.2
16.0
6.62
3
30
5.3
4.0
4.17
0
15
.8
.O
1.5
0
6
Results
The typical patient in
this study was mildly demented (mean 2.2 f .65; range l-4) employing the
revised CDR scaling (Table 1). The cognitive assessment score determined from the MMSE also
indicated the population was mildly demented (mean 16.2 f 6.62; range 3-30). There was relatively
little psychotic symptomatology observed (mean 0.8 + 1.5; range O-6). Variability in depressive
phenomena in this sample (mean 5.3 + 4.17; range O-15), was greater.
greater was used to indicate the presence of depression.
A CSDD cut off score of 8 or
Nearly one-fourth of the patients surpassed this
threshold (N= 15).
A multiple regression equation was computed to predict the CDR score from the set of predictors
considered simultaneously:
R=.63; R*=.40; p< JO01 (Fig. 1). Almost all of the variance in the
CDR explained by the model was due to the patient’s cognitive state as indexed by the MMSE; the
psychopathology scores did not contribute signitkantly to the variance explained.
Discussion
The CDR scale
is a commonly employed measure of severity of dementia. The scale requires the
evaluation of five levels of functional capability across six dimensions:
memory, orientation, judgement
and problem solving, community affairs, home and hobbies, and personal care. The results of this
study suggest that clinicians’ global rating of dementia severity using the CDR is strongly related to the
J. S. Kennedy et al.
778
patient’s cognitive state as measured by the MMSE. This supports the interpretation that the CDR is
insensitive to the presence of mild to moderately severe psychopathology in AD.
Conclusions
Employing the CDR this study suggests that clinician ratings of dementia severity are primarily
determined by the patient’s cognitive functions and are not significantly affected by mild to moderate
levels of psychopathology.
The influence of more severe levels of psychopathology in the AD
population on cliiician’s ratings of dementia stage using the CDR, and the relevance of the findings of
this study to non-AD demented populations requires further clarification.
2
30
1
2
2
20
M
w
S
E
7
5
5
3
4
8
4
1
10
2
1
2
4
4
2
2
1
1
0
1.0
2.0
3
4
5.6
CDR SCORE
I2
Psychoticism
.lO
Beta
E
.OOl>
.20
Depression
-.07
-.ll
>.20
KMSE
-.62
-.63
<.OOOl
R =.63; Rz=.40
Fig 1. Multiple regression of psychopathology and MMSE on CDR dementia ratings
Relation of psychopathology cognttive factors and dementia stage
779
Acknowledeement
The authors thank the staff of the Alzheimer’s Center at University Hospitals of Cleveland who
participated in collection of data presented here. The paper was previously presented at the
American College of Nemopsychopharmacology
Annual Meeting, San Juan, PR, December 1990.
Supported by NIMH grant NOS 6428498.
ALEKOPOULOS, G.S. ABRAMS, R.C., YOUNG, R.C., SHAMOIAN, C.A. (1988)
Cornell Scale for Depression in Dementia. Biol. Psychiatry a: 271-284.
FOLSTEIN, M.P., FOLSTEIN, S.E. and MC HUGH, P.R. (1975) Mini-Mental State’:
A Practical Method for Grading the Cognitive State of Patients for the Clinician.
J. Psychiitr. Res. 12: 189-198.
HUGHES, C.P., BERG, L., DANZIPER, W., COHEN, L.A. and MARTIN, R.L. (1982) A New
Clinical Scale for the Staging of Dementia. Br. J. Psychiatry M: 566-572.
MC KHANN, G., DRACHMAN, D., FOLSTEIN, M., KATZMAN, R., PRICE, D., and
STADLAN, E.M. (1984) Clinical Diagnosis of Alzheimer’s Disease: Report of the NINCDSADRDA Work Group under the Auspices of Department of Health and Human Services Task
Force on Alzheimer’s Disease. Neurology 3: 939-944.
MIRRA, S.S., VOGEL, S., HUGHES, J.P., BROWNLEE, L.M. and HEYMAN, A. (1988) The
CERAD Protocol for the Neuropathologic Assessment of Alzheimer’s Disease and Related
Disorders. Neurology 3 (Supp. 1): 413.
OVERALL, J.E. and GORHAM, D.R. (1962) The Brief Psychiatric Rating Scale. Psychol. Rep.
111:799-812.
Inquiries and reprint requests should be addressed to:
Dr. John S. Kennedy
Department of Psychiatry
Division of Geriatric Psychiatry
Vanderbilt University Medical Center
Nashville, TN 37212-8646, U.S.A.