Background There were comparison studies of regional cerebral blood flow between the responder group and the poor responder group to gabapentin and pregabalin in fibromyalgia (FM). Other brain imaging studies, such as positron emission tomography and fMRI, were needed to clarify the pathophysiology of FM and the characteristics of responders to gabapentin or pregabalin treatment.
Objectives We studied basal fMRI differences between milnacipran responders and non-responder in patients with FM.
Methods This research included 20 FM patients and 11 normal persons. We selected only females who were age and education level-matched in both groups to avoid bias. Tests were divided into clinical evaluation and fMRI imaging. Clinical evaluation was accomplished by principal investigator (rheumatology doctor) and included Korean fibromyalgia impact questionnaire (KFIQ), brief fatigue inventory (BFI), disease duration, widespread pain index (WPI), state anxiety inventory (SAI), and trait anxiety inventory (TAI). Changes in cerebral activation area were measured using BOLD contrast fMRI after application of both medium and high pressure stimuli to the left thumbnail bed.
Results After treatment with milnacipran, 10 patients were considered 'responders', with decrease in pain of greater than 50% as evaluated by visual analogue scale. The remaining 10 patients were considered 'poor responders'. The results showed that there were more increased activities in left insula and right inferior frontal gyrus of responder group in response to high pressure stimuli (p<0.05) and in anterior cingulate and left cingulate gyrus of non-responder group in response to high pressure stimuli (p<0.005).
Conclusions These regions can be susceptible to pain perception in these milnacipran treated FM patients.
Disclosure of Interest : None declared