Depression in dementia with Lewy bodies: A comparison with Alzheimer's disease
June
Depression in dementia with Lewy bodies: A comparison with Alzheimer's disease
Pai-Yi Chiu 0 1
Chein-Wei Wang 0
Chun-Tang Tsai 0
Shin-Hua Li 0
Chih-Li Lin 0
Te- Jen Lai 0
0 Editor: Kenji Hashimoto , Chiba Daigaku , JAPAN
1 Department of Neurology, Show Chwan Memorial Hospital , Changhua, Taiwan , 2 Department of Neurology, Taichung Lin-Shin Hospital , Taichung, Taiwan , 3 Department of Guidance and Counseling, National Changhua University of Education, Changhua, Taiwan, 4 Institute of Medicine, Chung Shan Medical University , Taichung, Taiwan , 5 Department of Psychiatry, Chung Shan Medical University Hospital , Taichung , Taiwan
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A total of 312 patients were investigated (AD/DLB = 241/71). The frequency of major
depression was significantly higher (p = 0.017) in DLB (19.7%) than in AD (8.7%). The
higher frequency of depression in DLB was not reproduced by using the NIMH-dAD criteria
(DLB: AD = 43.7%: 33.2%; p = 0.105). The severity of depression was higher in DLB than in
AD according to the Hamilton Depression Rating Scale (p < 0.001) and the Cornell Scale for
Depression in Dementia (p < 0.001). Among depressive symptoms, pervasive anhedonia
had the highest odds ratio in DLB compared with AD.
Conclusion
This is the first study using the NIMH-dAD criteria to investigate the frequency of depression
in DLB. Our study shows that co-morbid major depression is more frequent in DLB than in
AD. Pervasive anhedonia had the greatest value for the differential diagnosis of depression between DLB and AD.
Depression is highly associated with dementia, and this study will compare the frequencies,
severity, and symptoms of depression between dementia with Lewy bodies (DLB) and
Alzheimer's disease (AD).
OPEN ACCESS
Data Availability Statement: All relevant data are
within the paper.
Funding: The authors received no specific funding
for this work.
Competing interests: The authors have declared
that no competing interests exist.
Background
Methods
Results
Introduction
Clinical studies investigating the prevalence and severity of depression associated with dementia
have found that depression or depressive symptoms are among the most common behavioral
and psychological symptoms of Alzheimer's disease (AD) and dementia with Lewy bodies
(DLB) [1±3]. Depression is a nonmotor manifestation that has been frequently described in the
preclinical or early phase of Parkinson's disease (PD) as well as of DLB [
4,5,6
]. Two thirds of
dementia patients with depression at baseline were still depressed at the follow-up, more so in
DLB than in AD [
7
]. Unfortunately, depression has a great impact on the outcomes of dementia
patients and worsens the quality of life of dementia patients and their caregivers [
8,9
].
Depression is classically explained by the monoamine hypothesis, which proposes that
depression is related to a deficit of monoamines, particularly norepinephrine (NE), serotonin (5-HT),
and dopamine (DA) [
10
]. Recent functional imaging studies have indicated that depressed mood
is associated with brain areas that receive innervation from serotonergic projections from the
midbrain raphe nucleus and from the noradrenergic projections from the locus ceruleus, as well as
from dopaminergic projections from the ventral tegmental area [
10
] Besides the association of
depressed mood with a deficit of monoamines, the mesolimbic DA pathway is a key regulator of
interest/pleasure and dysfunctioning of the pathway may underlie the depression in PD [
10,11
].
Pathological studies examining the neural correlates of depression in primary dementia
have indicated cell loss in the locus ceruleus and substantial nigra [
12
]. Loss of rostral raphe
neurons may also contribute to depression in DLB [
13
]. However, the neural substrates
underlying depression in DLB and AD may be different. The major neurochemical difference
between AD and DLB is in the dopaminergic metabolism. A postmortem study of brains by
Piggott et al. from patients with PD, DLB, or AD, and elderly controls showed reduction in the
dopamine concentration in the putamen of DLB and PD patients, while there was no change
in AD patients [
14
]. This study also found that in DLB and PD, there is also reduced binding
to the dopamine uptake sites (presynaptic receptors) in the putamen (57%). There are no
changes in the uptake sites in AD as compared with the control values. Besides a dopaminergic
metabolism, the serotonergic system also differs between DLB and AD [15±18]. These studies
revealed that marked reduction of serotonin levels have been reported in the striatum,
neocortex and frontal cortex; however, DLB patients with major depression had relatively preserved
5HT transporter re-uptake sites, compared to those without.
One methodological concern in studies of depression associated with dementia is that
different rates of depression in dementia may be due to not only different dementia severity but
also different assessment too (...truncated)