A microdialysis study of topically applied diclofenac to healthy humans: Passive versus iontophoretic delivery

AbstractTopical application of NSAIDs is an alternative route to systemic administration when a local anti-inflammatory effect of the underlying tissue is a treatment option. The aim of the present microdialysis study was to assess and compare plasma and tissue levels of diclofenac when topically applied with or without iontophoresis in healthy adults. Fourteen healthy adults (26±9.4 years) were randomized to diclofenac applied by iontophoresis, or by a gel, in a crossover design. Diclofenac concentrations were measured in plasma and in microdialysis perfusates from the underlying tissues. Iontophoretic application resulted in the highest plasma concentration of 3.4±0.5ng/ml (SEM given) compared to 0.4ng/ml (at the detection limit) with gel, whereas no differences were observed between tissue concentrations for the two application methods, both being very low, below or around the detection limit. Iontophoresis caused skin reactions in 25% of the participants. Iontophoresis of diclofenac as compared to traditional topical application was not superior in order to increase the NSAID concentration locally and appears to have a higher frequency of skin reactions

Weight loss is effective for symptomatic relief in obese subjects with knee osteoarthritis independently of joint damage severity assessed by high-field MRI and radiography

Objective: With an increasing prevalence of older and obese citizens, the problems of knee osteoarthritis (KOA) will escalate. Weight loss is recommended for obese KOA patients and in a majority of cases this leads to symptomatic relief. We hypothesized that pre-treatment structural status of the knee joint, assessed by radiographs, 1.5 T magnetic resonance imaging (MRI) and knee-joint alignment, may influence the symptomatic changes following a significant weight reduction. Design: Patients were recruited from a Department of Rheumatology. Eligibility criteria were age above 50 years, body mass index >= 30 kg/m(2), primary KOA diagnosed according to the American College of Rheumatology (ACR) criteria and having verified structural damage. Patients underwent a 16 weeks dietary programme with formula products and counselling. MRI and radiographs of the most symptomatic knee were obtained at baseline and assessed for structural damage using the Boston-Leeds Osteoarthritis of the Knee Score, minimum joint space width and Kellgren Lawrence score. Imaging variables, muscle strength and degree of alignment, were examined as predictors of changes in Knee Osteoarthritis Outcome Score (KOOS) and Outcome Measures in Rheumatoid Arthritis Clinical Trials (OMERACT) - Osteoarthritis Research Society International (OARSI) Responder Criterion. Results: Structural damage at baseline assessed by imaging, muscle strength or knee-joint alignment showed no statistically significant association to changes in KOOS pain and function in daily living (r 0.05) or the OMERACT-OARSI Responder Criterion (OR 0.48-1.68; P-values > 0.13). Conclusions: Presence of joint damage did not preclude symptomatic relief following a clinically relevant weight loss in older obese patients with KOA. Neither muscle strength nor knee-joint alignment was associated with the degree of symptomatic relief. (C) 2012 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved