Phase 4 Study of Low Dose Prednisolone for Knee Osteoarthritis

Background: Osteoarthritis (OA), a common disabling condition, is the commonest type of arthritis worldwide. Knee OA is the 4th leading cause of disability in women. Pain is the leading symptom and is often chronic in nature leading to significant morbidity and decreased quality of life. Synovitis is prevalent in knee OA and treatment to relieve this synovitis may reduce pain.

Objectives: A randomized double-blind placebo-controlled trial will be conducted to assess whether 6 weeks of daily low dose oral prednisolone will improve pain, mobility and systemic low-grade inflammation, in the short term and to determine if it sustained long term at 12 weeks in older adults with moderate to severe knee OA.

Methods: 125 community-dwelling older adults aged 65 years and above with primary knee OA diagnosed according to the ACR criteria for diagnosis of primary OA of the knee will berandomized 1:1. Sixty three will receive 7.5 mg/day of prednisolone and 62 will receive placebo together with their usual therapy for 6 weeks. The primary outcome measure will be pain reduction. Secondary outcome measures will be reduction in systemic inflammation and improvements in physical functioning scores. Alterations in dosage of analgesic/NSAID drugs used will be recorded. Safety and tolerability were also assessed. Data will be collected at baseline, 6 weeks and at 12 weeks to determine any change in results from those obtained at 6 weeks. Exclusion criteria will include any inflammatory or serious medical condition.

Knee OA will be documented by radiographic examination using the Kellgren-Lawrence scale. Symptomatic OA will be defined as the need to take NSAIDs daily and LequesneAlgofunctional Index (LFI)score > 4. Clinical assessment will be include: Visual Analogue Pain Scale (VAS, 0-100), self-reported physical function as measured with the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), WOMAC pain and stiffness scores, and six-minute walk distance (6MWD). All patients will undergo a physical examination and will be questioned about the number of flares, pain and analgesic use. Blood samples will be collected and serum levels of IL-1, IL-6, TNF-alpha and hsCRP will be measured in all patients.