Genetic and epidemiological aspect of Complex Regional Pain Syndrome

Abstract

Complex Regional Pain Syndrome (CRPS) is a painful disorder affecting one or more extremities. CRPS is characterized by various combinations of sensory, autonomic and motor disturbances. Genetic factors are suggested to play a role in CRPS, but this has not been extensively studied. Therefore the aims of this thesis were to study the contribution and the size of the contribution of genetic factors in CRPS and to identify possible susceptibility and causative genes for CRPS. In our studies we have shown that CRPS may develop without a noxious event and it has been suggested that such patients have a larger genetic predisposition. Furthermore we have found that CRPS may occur in a familial form, but did not observe a clear inheritance pattern. We calculated a measure of familial aggregation. This study yielded no indications for a large overall increased risk of developing CRPS for siblings of CRPS patients. Significant associations were found with CRPS and dystonia and two HLA-B62 and HLA-DQ8. We also evaluated the presence of causative mutations in known primary dystonia genes and causative mutations in the SCN9A gene. No such mutations were identified, indicating that these genes do not seem to play a major role in CRPS.