Has Catechol-O-Methyltransferase Genotype (Val158Met) an Influence on Endocrine, Sympathetic Nervous and Humoral Immune Systems in Women With Fibromyalgia Syndrome?

OBJECTIVE:Stress can play an important role in etiology of fibromyalgia syndrome (FMS) by activating the hypothalamic-pituitary-adrenal (HPA) axis, the sympathetic nervous system (SNS), and altering the immune system. The current study examined the influence of catechol-O-methyltransferase (COMT) Val158Met genotypes on salivary markers of HPA axis (cortisol), SNS (α-amylase), and immune (IgA) systems in women with FMS. METHODS:Seventy-six women with FMS diagnosed according to the American College of Rheumatology criteria participated in the study. Salivary cortisol, α-amylase activity, salivary flow rate, and IgA concentration were collected from nonstimulated saliva. A numerical pain rate scale (0 to 10) was used to assess the intensity of pain, whereas functional ability was determined using the Fibromyalgia Impact Questionnaire (FIQ). After amplifying Val158Met polymorphisms by polymerase chain reaction, 3 COMT genotypes were consideredVal/Val, Val/Met, and Met/Met. RESULTS:Women with FMS with the Met/Met genotype reported higher α-amylase activity, lower salivary flow rate, and lower IgA concentration than those women with FMS carrying the Val/Met (P