BERLIN – Prednisolone improves pain scores in patients with moderate to severe knee osteoarthritis by nearly one-third, according to the WOMAC pain scale, compared with patients on placebo, according to a new study presented at the annual European Congress of Rheumatology.
"Given the limitations of current nonspecific symptom-relieving drugs such as NSAIDs, we need medications that control pain in the medium to long term as well as short term," said Dr. Anna Abou-Raya of the University of Alexandria (Egypt).
Dr. Anna Abou-Raya
Dr. Abou-Raya conducted a randomized, double-blind, controlled trial to assess whether 6 weeks of daily, low-dose oral prednisolone would lessen pain, improve mobility, and ease systemic low-grade inflammation, as well as be sustained over 12 weeks in older adults with moderate to severe knee osteoarthritis (OA).
In all, 125 adults older than 65 years were recruited from among OA patients who attended her institution’s outpatient clinic. Patients met ACR (American College of Rheumatology) clinical and radiographic criteria of primary knee OA and had a mean pain score greater than 4 on a scale of 0-10 in the week prior to treatment that had occurred for at least 14 days a month for 3 months prior to randomization.
Oral prednisolone (7.5 mg/day) was given to 63 patients, and placebo was given to 62; all completers were followed up at 6 and 12 weeks. All patients received physical examination and were reviewed for their pain levels, flares, and analgesic use.
The primary outcome was pain reduction, with secondary outcomes of systemic inflammation and improvement in physical functioning score. Dr. Abou-Raya assessed knee OA using the Kellgren-Lawrence scale; clinical function on a 0-100 VAS (Visual Analogue Scale); self-reported physical function, pain, and stiffness as reported by the WOMAC (Western Ontario and McMaster Universities) osteoarthritis index; and a 6-minute walk distance test. Blood levels of interleukin-1 (IL-1), IL-6, tumor necrosis factor (TNF)–alpha, and high-sensitivity C-reactive protein (hsCRP) were also measured.
"There was a significantly greater absolute change from baseline in all three subscale scores – function, pain, and stiffness – [at both] 6 and 12 weeks in the prednisolone group," compared with the placebo group.
WOMAC pain scores showed a change of –3.4 (95% confidence interval, –5.15 to –2.99) over 12 weeks on prednisolone, compared with –0.4 (95% CI, –0.193 to –0.41) for patients on placebo (P = .001). WOMAC function scores also showed improvement in the prednisolone group, with a change from baseline of –10.9 (95% CI, –4.46 to –2.31) over 12 weeks, compared with –0.4 (95% CI, –0.196 to –0.29) in the placebo group (P = .005).
"The mean number of analgesic users decreased significantly in the intervention group" compared with the placebo group at both 6 and 12 weeks when compared with baseline, added Dr. Abou-Raya.
The researcher also found that mean levels of inflammatory markers IL-1, IL-6, TNF-alpha, and hsCRP were all reduced in the prednisolone group vs. the placebo group. For example, IL-1 levels at 6 weeks were 18.7 pg/mL vs. 25 pg/mL in the prednisolone and placebo groups, respectively (P = .005), and this was maintained at 12 weeks. The hsCRP levels were 2.3 mg/L vs. 3.6 mg/L at 6 weeks for the prednisolone and placebo groups, respectively (P = .005), and these were also maintained at 12 weeks.
"There was a significant improvement in the 6-minute walk distance test at 6 and 12 weeks," reported Dr. Abou-Raya, with an absolute change from baseline of 7.6 m in the prednisolone group compared with 0 m in the placebo arm.
Treatment-related adverse effects were similar in both groups, with no serious events recorded.
"The findings may provide evidence of efficacy and tolerability of low-dose oral prednisolone in reducing pain and subsequently improving function in older adults with knee OA; however, we need larger scale longitudinal studies to further verify this information," concluded Dr. Abou-Raya.
Dr. Abou-Raya reported that she had no relevant conflicts of interest.