Impact of transdermal fentanyl on quality of life in rheumatoid arthritis.

OBJECTIVES: The purpose of the study was to investigate the effectiveness and tolerability of transdermal fentanyl in a treatment regimen in patients with rheumatoid arthritis (RA). METHODS: Two hundred twenty-six patients (mean age 66 y) with severe pain caused by RA who had not previously been treated with transdermal fentanyl were included in this prospective, open-label study. Pain intensity, functional impairment, and well-being were documented prospectively for 30 days after treatment with transdermal fentanyl had been initiated. Patients evaluated pain on an 11-point numerical rating scale. Quality of sleep, daily and social functioning, and treatment satisfaction were rated using 5-point categorical rating scales. General well-being was assessed by the Marburg questionnaire. RESULTS: Adding transdermal fentanyl to the ongoing RA therapy reduced pain intensity significantly from 8.0 (7.82 to 8.18) to 4.0 (3.75 to 4.25). Mean functional impairment due to pain also decreased significantly from "severe" at the beginning to "mild to moderate." Treatment with transdermal fentanyl also led to a significant improvement by approximately 1.5 units for all items in the Marburg questionnaire on general well-being. At the end of the study, nearly all patients were satisfied with the pain treatment. Transdermal fentanyl was generally well tolerated. The most frequent side effects were nausea (9.7%) and vomiting (7.1%). DISCUSSION: Patients with pain caused by RA improved in terms of pain intensity, sleep, function, and general well-being when transdermal fentanyl was added to the treatment regimen. Treatment satisfaction was high. Transdermal fentanyl also demonstrated good tolerability over a period of 30 days.

Dissociable neural responses related to pain intensity, stimulus intensity, and stimulus awareness within the anterior cingulate cortex: a parametric single-trial laser functional magnetic resonance imaging study.

Neuroimaging studies have demonstrated activations in the anterior cingulate cortex (ACC) related to the affective component of pain, but not to stimulus intensity. However, it is possible that the low spatial resolution of positron emission tomography, as used in the majority of these studies, obscured areas coding stimulus intensity. We revisited this issue, using a parametric single-trial functional magnetic resonance imaging design, and investigated pain, stimulus intensity, and stimulus awareness (i.e., pain unrelated) responses within the ACC in nine healthy volunteers. Four different stimulus intensities ranging from warm to painful (300-600 mJ) were applied with a thulium yttrium-aluminum granite infrared laser in a randomized order and rated by the subjects on a five point scale (P0-P4). Pain-related regions in the ventral posterior ACC showed a response that did not distinguish between innocuous trials (P0 and P1) but showed a positive linear relationship with the blood oxygenation level-dependent contrast signal for painful trials (P2-P4). Regions in the dorsal anterior ACC along the cingulate sulcus differentiated between P0 (not perceived) and P1 but exhibited no additional signal increase with P2; these regions are related to stimulus awareness and probably to cognitive processing. Most importantly, we identified a region in the dorsal posterior ACC showing a response that discriminated between nonpainful trials (P0 and P1); therefore, this region was simply related to basic sensory processing and not to pain intensity. Stimulus-related activations were all located adjacent to the cingulate motor area, highlighting the strategic link of stimulus processing and response generation in the posterior ACC.