HealthDay News — For patients with chronic osteoarthritis (OA) pain, duloxetine added to usual care has no effect compared with usual care alone, according to a study published online Jan. 6 in Arthritis & Rheumatology.
Jacoline J. van den Driest, M.D., from the University Medical Center in Rotterdam, Netherlands, and colleagues examined the effectiveness of duloxetine added to usual care for patients with chronic OA pain. Patients with chronic OA of the hip or knee, with insufficient response to acetaminophen or nonsteroidal anti-inflammatory drugs, were included. A total of 132 patients were randomly assigned to duloxetine added to usual care (66 patients from 31 practices) or usual care alone (66 patients from 34 practices).
The researchers observed no differences in the Western Ontario and McMaster Universities Arthritis Index (WOMAC) pain domain at 3 or 12 months (adjusted differences, −0.58 [95% confidence interval, −1.80 to 0.63] and −0.26 [95% confidence interval, −1.86 to 1.34], respectively). No effect of duloxetine was seen in the subgroup of patients with symptoms of centralized pain (adjusted difference, −0.32; 95% confidence interval, −2.32 to 1.67).
“We did not find a clinically relevant or statistically significant effect of duloxetine for WOMAC pain at  months, nor for the other outcomes or at other time points and can rule out the presence of a clinically relevant effect for the total group,” the authors write.
One author disclosed financial ties to Pfizer.