Arthritis & Rheumatism, Volume 62,
November 2010 Abstract Supplement
Abstracts of the American College of
Rheumatology/Association of Rheumatology Health Professionals
Annual Scientific Meeting
Atlanta, Georgia November 6-11, 2010.
Improvement in Multiple Dimensions of Fatigue in Fibromyalgia Patients Treated with Duloxetine.
Arnold2, Lesley M., Wang1, Fujun, Ahl1, Jonna, Gaynor1, Paula, Wohlreich1, Madelaine
In addition to widespread pain, fatigue is one of the most common and disabling symptoms of fibromyalgia. Fatigue was assessed as a secondary objective in this 2-phase 24-week trial of duloxetine in patients with ACR-defined fibromyalgia.
Outpatients 1865 years of age, with Brief Pain Inventory average pain >=4 were randomized to duloxetine 60120 mg/d (N=263) or placebo (N=267) for the 12-week acute phase. At Week 12, all patients in the placebo group were switched to double-blind treatment with duloxetine for the 12-week extension phase. Fatigue was assessed at baseline and every 4 weeks by the Multidimensional Fatigue Inventory (MFI), which is comprised of the following subscales: General Fatigue (GF), Physical Fatigue (PF), Mental Fatigue (MF), Reduced Activity (RA), and Reduced Motivation (RM). The frequency of treatment-emergent adverse events (TEAE) that might be associated with fatigue, such as fatigue, insomnia and somnolence, was also assessed. Changes from baseline in MFI subscale scores during the acute phase, and from Week 12 during the extension phase were analyzed by mixed-effects model repeated measures analysis. For the acute phase, the model included baseline value, acute phase treatment, investigator, visit, treatment-by-visit, and baseline-by-visit interactions; for the extension phase, the model included: investigator, visit, Week 12 baseline score and baseline-by-visit interaction (the model was fitted separately for patients randomized to duloxetine and patients randomized to placebo then switched to duloxetine in the extension phase).
At the end of the acute phase, patients who received duloxetine versus placebo had significantly reduced scores on each MFI subscale (all p<.05) indicating improvement (Arnold et al). In the extension phase, mean MFI subscale scores indicated that improvement was maintained for patients who received duloxetine for up to 24 weeks (n=176). For placebo-treated patients who were switched to duloxetine (n=187), significant within-group improvement in MFI subscale scores was observed at Weeks 16, 20 and 24 for PF, Weeks 20 and24 for GF, Week 20 for MF, and Weeks 20 and 24 for RA. Individual subscale scores after switching to duloxetine were similar to those for patients who received duloxetine for 24 weeks. This suggests that patients treated with duloxetine for 6 months maintained improvement in several dimensions of fatigue assessed by the MFI, and that placebo patients switched to duloxetine quickly reached the level of improvement in fatigue observed in the active treatment group. In the acute phase, TEAE rates of fatigue, somnolence and insomnia were: 9.5%, 5.7% and 9.1% for duloxetine; 7.1%, 3.4%, and 7.1% for placebo. In the extension phase, overall rates for these TEAEs were: fatigue 4.1%; somnolence, 2.5%; and insomnia, 3.6%.
Treatment with duloxetine significantly improved multiple dimensions of fatigue in patients with fibromyalgia, and improvement was maintained with duloxetine treatment up to 24 weeks.
To cite this abstract, please use the following information:
Arnold, Lesley M., Wang, Fujun, Ahl, Jonna, Gaynor, Paula, Wohlreich, Madelaine; Improvement in Multiple Dimensions of Fatigue in Fibromyalgia Patients Treated with Duloxetine. [abstract]. Arthritis Rheum 2010;62 Suppl 10 :105