The relationship between the dopaminergic system and depressive symptoms in cervical dystonia.
OBJECTIVE
Cervical dystonia (CD) is associated with tremor/jerks (50%) and psychiatric complaints (17-70%). The dopaminergic system has been implicated in the pathophysiology of CD in animal and imaging studies. Dopamine may be related to the motor as well as non-motor symptoms of CD. CD is associated with reduced striatal dopamine D2/3(D2/3) receptor and increased dopamine transporter (DAT) binding. There are differences in the dopamine system between CD patients with and without jerks/tremor and psychiatric symptoms.


METHODS
Patients with CD and healthy controls underwent neurological and psychiatric examinations. Striatal DAT and D2/3 receptor binding were assessed using [123I]FP-CIT and [123I]IBZM SPECT, respectively. The ratio of specific striatal to non-specific binding (binding potential; BPND) was the outcome measure.


RESULTS
Twenty-seven patients with CD and 15 matched controls were included. Nineteen percent of patients fulfilled the criteria for a depression. Striatal DAT BPNDwas significantly lower in depressed versus non-depressed CD patients. Higher DAT BPNDcorrelated significantly with higher scores on the Unified Myoclonus Rating Scale (UMRS). The striatal D2/3 receptor BPNDin CD patients showed a trend towards lower binding compared to controls. The D2/3 BPNDwas significantly lower in depressed versus non-depressed CD patients. A significant correlation between DAT and D2/3R BPNDwas found in both in patients and controls.


CONCLUSIONS
Alterations of striatal DAT and D2/3 receptor binding in CD patients are related mainly to depression. DAT BPNDcorrelates significantly with scores on the UMRS, suggesting a role for dopamine in the pathophysiology of tremor/jerks in CD.
Department of Neurology, Academic Medical Centre, Amsterdam, The Netherlands.
E
http://orcid.org/0000-0002-9288-109X
E
Zoons
Department of Neurology, University Medical Centre, Groningen, The Netherlands.
M A J
MAJ
Tijssen
Department of Neurology, Academic Medical Centre, Amsterdam, The Netherlands.
Y E M
YEM
Dreissen
Department of Neurology, Academic Medical Centre, Amsterdam, The Netherlands.
J D
JD
Speelman
Department of Neurology, University Medical Centre, Groningen, The Netherlands.
M
M
Smit
Department of Nuclear Medicine, Academic Medical Centre, PO Box 22660, 1100 DD, Amsterdam, The Netherlands. j.booij@amc.uva.nl.
J
J
Booij
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D003863:Depression / Q000150:complications*; D004298:Dopamine / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017448:Receptors, Dopamine D2 / Q000378:metabolism; D050637:Receptors, Dopamine D3 / Q000378:metabolism; D015899:Tomography, Emission-Computed, Single-Photon; D014103:Torticollis / Q000150:complications / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000523:psychology*
D017448:Receptors, Dopamine D2; D050637:Receptors, Dopamine D3; D004298:Dopamine
Cervical dystonia; Depression; Dopamine D2/3 receptor; Dopamine transporter (DAT); SPECT