Evaluation of Cognitive Performance in Patients with Fibromyalgia Syndrome: A Case-Control Study.

Patients with fibromyalgia syndrome tend to report deficits in cognitive functions; however, there is no clear consensus on which cognitive domains are impaired. The aim of this study was to compare the differences in cognitive performance between a group of patients with fibromyalgia syndrome and a group of pain-free subjects controlling for the covariables anxiety, depression, and sleep quality. In total, 130 patients with fibromyalgia syndrome and 111 pain-free subjects with an average age of 54.96 years completed the evaluation protocol consisting of sociodemographic data, psychological data, and neurocognitive tests. All data were collected from May 2022 to May 2023. Multivariate analyses of covariance (MANCOVAs) were conducted to assess intergroup differences in all neurocognitive tests. MANCOVA analyses showed that the group of patients with fibromyalgia showed a worse cognitive performance than the group of pain-free subjects after controlling for anxiety, depression, and sleep quality. This study found that fibromyalgia patients exhibited worse cognitive performance and executive function than pain-free subjects. Thus, cognitive performance seems to not be related with anxiety, depression, or sleep quality in our sample of women with FMS.

Association of OPRM1 rs1799971, HTR1B rs6296 and COMT rs4680 polymorphisms with clinical phenotype among women with fibromyalgia.

To investigate the association between three selected pain polymorphisms and clinical, functional, sensory-related, psychophysical, psychological or cognitive variables in a sample of women with fibromyalgia (FMS). One hundred twenty-three (n = 123) women with FMS completed demographic (age, height, weight), clinical (years with pain, intensity of pain at rest and during daily living activities), functional (quality of life, physical function), sensory-related (sensitization-associated and neuropathic-associated symptoms), psychophysical (pressure pain thresholds), psychological (sleep quality, depressive and anxiety level) and cognitive (pain catastrophizing, kinesiophobia) variables. Those three genotypes of the OPRM1 rs1799971, HTR1B rs6296 and COMT rs4680 single nucleotide polymorphisms were obtained by polymerase chain reactions from no-stimulated whole saliva collection. No significant differences in demographic, clinical, functional, sensory-related, psychophysical, psychological and cognitive variables according to OPRM1 rs1799971, HTR1B rs6296 or COMT rs4680 genotype were identified in our sample of women with FMS. A multilevel analysis did not either reveal any significant gene-to-gene interaction between OPRM1 rs1799971 x HTR1B rs6296, OPRM1 rs1799971 x COMT rs4680 and HTR1B rs6296 x COMT rs4680 for any of the investigated outcomes. This study revealed that three single nucleotide polymorphisms, OPRM1 rs1799971, HTR1B rs6296 or COMT rs4680, mostly associated with chronic pain were not involved in phenotyping features of FMS. Potential gene-to-gene interaction and their association with clinical phenotype in women with FMS should be further investigated in future studies including large sample sizes.