Do omega-6 and trans fatty acids play a role in complex regional pain syndrome? A pilot study.
OBJECTIVE
The study aims to compare the omega-6 (n-6) and omega-3 (n-3) highly unsaturated fatty acids (HUFA), and trans fatty acid (trans FA) status of Complex Regional Pain Syndrome (CRPS) patients to pain-free controls.


METHODS
Case control study. Setting. The setting was at a multidisciplinary rehabilitation center.


METHODS
Twenty patients that met the Budapest research diagnostic criteria for CRPS and 15 pain-free control subjects were included in this study. Outcome Measures. Fasting plasma fatty acids were collected from all participants. In CRPS patients, pain was assessed using the McGill Pain Questionnaire-Short Form. In addition, results from the perceived disability (Pain Disability Index), pain-related anxiety (Pain Anxiety Symptom Scale Short Form), depression (Center for Epidemiologic Studies Depression Scale Short Form), and quality of life (Short Form-36 [SF-36]) were evaluated.


RESULTS
Compared with controls, CRPS patients demonstrated elevated concentrations of n-6 HUFA and trans FA. No differences in n-3 HUFA concentrations were observed. Plasma concentrations of the n-6 HUFA docosatetraenoic acid were inversely correlated with the "vitality" section of the SF-36. Trans FA concentrations positively correlated with pain-related disability and anxiety.


CONCLUSIONS
These pilot data suggest that elevated n-6 HUFA and trans FA may play a role in CRPS pathogenesis. These findings should be replicated, and more research is needed to explore the clinical significance of low n-6 and trans FA diets with or without concurrent n-3 HUFA supplementation, for the management of CRPS.
Ramsden
Christopher
C
Rehabilitation Institute of Chicago, Department of Physical Medicine and Rehabilitation, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA. chris.ramsden@nih.gov
Gagnon
Christine
C
Graciosa
Joseph
J
Faurot
Keturah
K
David
Robert
R
Bralley
J Alexander
JA
Harden
R Norman
RN
D000328:Adult; D016022:Case-Control Studies; D020918:Complex Regional Pain Syndromes / Q000097:blood* / Q000503:physiopathology; D015525:Fatty Acids, Omega-3 / Q000097:blood*; D043371:Fatty Acids, Omega-6 / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D010865:Pilot Projects; D011788:Quality of Life; D011795:Surveys and Questionnaires; D044242:Trans Fatty Acids / Q000097:blood*
D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6; D044242:Trans Fatty Acids