Gender, genetics, and other risk factors increasing vulnerability to fibromyalgia

Fibromyalgia (FM) syndrome is a common chronic pain syndrome with predictable clinical features that result from altered neurophysiological functions of the pain-related nervous system. Relevant mechanisms range from sensitization within the brain and spinal cord to augmented peripheral mechanoreceptor inputs, leading to pain and tenderness. The clinical picture may be seen as a final common pathway resulting from a range of inputs that vary between individuals. Subgroups of FM may reflect these inputs. There are many factors that increase vulnerability to FM, in particular gender and age. The majority of patients can identify a trigger that precedes development of the syndrome. Many triggers relate to a precipitating event that associates with psychological distress, often acting on a longer-term background of life-stress. Reactions to life predicaments, involving coping skills, may act as factors that promote ongoing sensitization. Genetic variability in a number of pain-related chemicals might also modulate the response of the pain system to any given input. Of particular interest are those that relate to the mono-amines serotonin, norepinephrine, and dopamine. Better clinical characterization of large cohorts of FM patients will enhance the value of techniques such as single nucleotide polypeptide analysis. Further knowledge of factors increasing vulnerability to FM will allow for early intervention and improve outcomes of this high-impact disorder.