Pain in Parkinson's disease associated with COMT gene polymorphisms.
BACKGROUND
PD patients present high incidence of pain with unknown pathogenesis. Objective. We investigated the relation of COMT polymorphisms rs4633 and rs6267 with PD pain.


METHODS
One hundred PD patients and 105 controls were evaluated with simplified Mc GILL pain scale and VAS scale. PD patients were assessed with H&Y grade, UPDRS score, and HAMD scale. Polymorphisms rs4633 and rs6267 were detected by PCR and direct sequencing.


RESULTS
Fifty-seven percent of PD patients experienced pain, consisting of PD-related pain (64.91%) (the majority was dystonia pain) and non-PD-related pain (35.09%) (psychogenic pain was most frequent). The frequency of rs6267 genotype "GT/TT" and allele "T" was higher in PD pain. No difference was observed in frequencies of rs4633 between PD pain and without pain. UPDRS and depression score were higher in PD pain. The onset age was earlier in PD-related pain (57.43 ± 19.71) than non-PD-related pain (63.36 ± 6.88).


CONCLUSIONS
PD patients possess a high prevalence of pain. Dystonia pain was the most frequent type of PD-related pain. COMT gene rs6267 allele "T" associated with PD pain. PD pain was influenced by disease severity and depression. PD onsets earlier in patients with PD-related pain than non-PD-related pain.
Department of Neurology, Second Hospital of Harbin Medical University, Harbin, Heilongjiang Province 150086, China.
Wanjun
W
Li
Department of Neurology, Second Hospital of Harbin Medical University, Harbin, Heilongjiang Province 150086, China.
Yongqian
Y
Chen
Department of Neurology, Second Hospital of Harbin Medical University, Harbin, Heilongjiang Province 150086, China.
Bowen
B
Yin
Department of Neurology, Second Hospital of Harbin Medical University, Harbin, Heilongjiang Province 150086, China.
Limei
L
Zhang
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002394:Catechol O-Methyltransferase / Q000235:genetics*; D003863:Depression / Q000150:complications / Q000235:genetics; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000150:complications / Q000235:genetics*; D010147:Pain Measurement; D010300:Parkinson Disease / Q000150:complications / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D012720:Severity of Illness Index
C588010:COMT protein, human; D002394:Catechol O-Methyltransferase