Objectives: Fibromyalgia syndrome (FMS) patients have multiple symptoms, including mental symptoms such as depression. Natural killer T (NKT) cells have shown to be correlated with depression. However, up to now there is no information regarding the role of CD3+CD56+NKT cells in FMS patients, especially in the intensity of mental symptoms. The present study aimed to observe the role of CD3+CD56+NKT cells level in FMS patients in relation to the intensity of depression.
Methods: Ninety-six female patients who matched definition of FMS were divided into subgroups of depressions according to Hospital Anxiety and Depression Scale (HADS) score (HADS-Depression <8; 8-10; and >10). CD3+CD56+NKT cells from peripheral blood were measured by fluorescence-activated cell sorting methods.
Results: ANOVA test in the subgroup of depression of FMS patient showed significant differences. Additionally, the differences were observed in HADSD <8 and >10. The use of antidepressant significantly altered the level of CD3+CD56+NKT cells. A blocking variable ANCOVA with antidepressant as covariate showed main effects in the subgroup of depression, however, the interaction of antidepressant and the subgroup of depression did not influence the level of CD3+CD56+NKT cells.
Conclusions: These results suggest that CD3+CD56+NKT cells could play a role as a mediator in mental symptom such as depression in FMS patients. It seems the role of antidepressant in the mood intensity is not mediated by CD3+CD56+NKT cells in FMS patients. Additionally, subgrouping FMS patients based on the intensity of mental symptoms may help to optimise the treatments.