ABSTRACT
OBJECTIVES: The aim of this study was to evaluate the levels of 6-sulphatoxymelatonin (6-SMT) in the urine of patients with fibromyalgia (FM) and correlate them with the score obtained by these patients in four clinical assessment instruments. METHODS: Fifty-eight women with primary FM and 39 healthy women matched for age and body mass index were included in the study sample. The levels of 6-SMT were evaluated in urine collected from 8 pm until 8 am the next day by the immunosorbent assay. For the clinical evaluation we used the Fibromyalgia Impact Questionnaire (FIQ); Pittsburg Sleep Quality Index (PSQI); Medical Outcomes Study 36-item Short-Form Health Survey (SF-36) and Satisfaction with Life Scale (SWLS). Data normality was assessed using the Kolmogorov-Smirnov test, the differences between groups by means of the Mann-Whitney test and correlation analysis by Spearman's correlation test. RESULTS: The levels of 6-SMT in the urine of patients with FM were significantly lower than those found in the urine of healthy controls. The score obtained by patients with FM was significantly different from the score achieved by the healthy controls in the four assessment tools. However, no significant correlation between urinary levels of 6-SMT and scores on assessment instruments was observed. CONCLUSIONS: The results of this study do not discard the involvement of melatonin in the pathophysiology of FM, but may suggest that changes in melatonin levels when associated with other neuroimmunoendocrine changes may impact directly and negatively on the manifestation of symptoms that make up the clinical picture of FM.
Subject(s)
Fibromyalgia/urine , Melatonin/analogs & derivatives , Adult , Biomarkers/urine , Brazil , Case-Control Studies , Down-Regulation , Enzyme-Linked Immunosorbent Assay , Female , Fibromyalgia/diagnosis , Fibromyalgia/physiopathology , Fibromyalgia/psychology , Health Status , Humans , Melatonin/urine , Middle Aged , Patient Satisfaction , Predictive Value of Tests , Quality of Life , Severity of Illness Index , Sleep , Statistics, Nonparametric , Surveys and Questionnaires , Syndrome , UrinalysisABSTRACT
OBJECTIVES: The aim of this study was to evaluate the plasma levels of IL-17A in fibromyalgia patients, and to look for any correlations between this data and the concentrations of some pro- and anti-inflammatory cytokines. METHODS: We performed a study including 58 fibromyalgia patients and 39 healthy women matched for age and body mass index. The plasma levels of IL-17A and other pro- and anti-inflammatory cytokines were measured by using the technique of cytometric bead array (CBA). The analysis of differences between groups was performed using Mann-Whitney test and the analysis of the correlations by Spearman's correlation test. RESULTS: The analyses showed that fibromyalgia patients present increased levels of IL-17A. They also revealed that plasma concentrations of IL17A positively correlate with levels of IL-2, IL-4 and IL-10, TNF and IFNγ. CONCLUSIONS: As far as we are aware, this is the first study to demonstrate increased levels of IL17A in fibromyalgia patients. The positive correlation between the levels of IL-17A and of other cytokines strengthens the hypothesis of the involvement of inflammatory mechanisms in the development of this syndrome.
