Serum ARGS-aggrecan in a phase 2 clinical trial targeting osteoarthritis.

OBJECTIVE: To monitor serum concentrations of the aggrecan alanine-arginine-glycine-serine (ARGS) neoepitope in a clinical trial of a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)-5 inhibition as disease-modifying therapy of knee osteoarthritis, and to investigate relationships between reduction in ARGS and change in cartilage thickness, knee-related pain and function. DESIGN: ROCCELLA trial participants received once-daily oral S201086 75, 150 or 300 mg, or placebo, for 52 weeks. Serum was collected at baseline, 4, 12, 28 and 52 weeks, and 2 weeks post-treatment with ARGS measured by an in-house immunoassay. Change from baseline to week 52 in central medial femorotibial compartment cartilage thickness was measured by magnetic resonance imaging, function and pain by Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) subscores. Associations between cumulative change in ARGS and change in cartilage thickness or WOMAC subscores were evaluated by linear regression. RESULTS: S201086 reduced serum levels of ARGS in a dose-dependent manner throughout the treatment period. Maximal reduction was at 4 weeks with a 58.5% [95% CI 60.8%, 56.2%] reduction of ARGS compared to baseline for 300 mg S201086. Two weeks post-treatment, ARGS concentrations rebounded with a dose-dependent overshoot compared to baseline levels. Cumulative change of ARGS concentration from baseline to week 52 had no effect on change in cartilage thickness (slope -0.8×10-6 [-2.9×10-6, 1.3×10-6]) or change in WOMAC pain and function (slopes -30×10-6 [-64×10-6, 5.2×10-6] and -97×10-6 [-214×10-6, 20×10-6], respectively) at week 52. CONCLUSION: Systemic inhibition of ADAMTS-5 resulted in markedly reduced serum ARGS, but change in serum ARGS concentrations showed no association with the progression of cartilage thinning, or patient reported pain and function.

The coexistence of diabetes, hypertension and obesity is associated with worse pain outcomes following exercise for osteoarthritis: A cohort study on 80,893 patients.

OBJECTIVES: To investigate how the co-occurrence of diabetes, hypertension and overweight/obesity is associated with pain following an exercise intervention for knee and hip osteoarthritis (OA). METHODS: Register-based cohort study. We included people from the Swedish Osteoarthritis Register who underwent education and exercise for knee or hip OA. Diabetes and hypertension were defined using medical records and dispensation of medication. Body Mass Index (BMI) was used to identify people with overweight (≥25 to <30), and obesity (≥30). We used linear mixed-effect models with patients nested into clinics to estimate the associations between the exposures and pain (Numeric Rating Scale 0-10), adjusting for age, sex, education, and physical activity. RESULTS: We analysed 80,893 patients with knee or hip OA. The accumulation of metabolic conditions was associated with worse pain at baseline and follow-ups. When obesity, hypertension and diabetes coexisted, patients treated for knee OA reported more pain at baseline (adjusted mean pain difference 0.9 [95 %CI: 0.8; 1.0]), 3 months (1.0 [0.9; 1.1]) and 12 months (1.3 [1.1; 1.4]) compared to those without any of the conditions. Similar results were observed for patients treated for hip OA when obesity, hypertension and diabetes coexisted (baseline (0.7 [0.5; 0.8], 3 (0.8[0.6; 1.0]) and 12 months (1.1[0.8; 1.3]). CONCLUSIONS: When diabetes, hypertension and obesity coexist with OA, patients not only experience heightened baseline pain compared to metabolically healthy individuals, but the disparity increases after an education and exercise intervention suggesting that a one-size-fits-all approach may be inadequate in addressing the complex interplay between metabolic health and OA.

Early anterior cruciate ligament reconstruction does not affect 5 year change in knee cartilage thickness: secondary analysis of a randomized clinical trial.

OBJECTIVE: To compare 5-year change in femorotibial cartilage thickness in 121 young, active adults with an acute anterior cruciate ligament (ACL) tear randomized to a strategy of structured rehabilitation plus early ACL reconstruction (ACLR) or structured rehabilitation plus optional delayed ACLR. DESIGN: 62 patients were randomized to early ACLR, 59 to optional delayed ACLR. Magnetic resonance imaging (MRI) was acquired within 4 weeks of injury, at two- and 5-years follow-up. Main outcome was 5-year change in overall femorotibial cartilage thickness. Secondary outcomes included the location-independent cartilage ChangeScore, summarizing thinning and thickening in 16 femorotibial subregions. An exploratory as-treated comparison was performed additionally. RESULTS: Baseline and at least one follow-up MRI were available for 117 patients. Over 5 years, a comparable increase in overall femorotibial cartilage thickness was observed for patients randomized to early ACLR (n = 59) and patients randomized to optional delayed ACLR (n = 58, adjusted mean difference: -5 µm, 95% CI: [-118, 108]µm). However, the location-independent cartilage ChangeScore was greater in those treated with early ACLR than in patients treated with optional delayed ACLR (adjusted mean difference: 403 µm [119, 687]µm). As-treated analysis showed no between-group differences for the main outcome, while the location-independent cartilage ChangeScore was greater for patients treated with early (adjusted mean difference: 632 µm [268, 996]µm) or delayed ACLR (adjusted mean difference: 449 µm [108, 791]µm) than for patients treated with rehabilitation alone. CONCLUSIONS: In young active adults with acute ACL-injury, choice of treatment strategy for the injured ACL did not modify the magnitude of 5-year change in overall femorotibial cartilage thickness. TRIAL REGISTRATION: ISRCTN84752559.

Low risk for hip fracture and high risk for hip arthroplasty due to osteoarthritis among Swedish farmers.

We aimed to study the risk of hip fracture and risk of hip arthroplasty among farmers in Sweden. Our results indicate that farming, representing an occupation with high physical activity, in men is associated with a lower risk of hip fracture but an increased risk of hip arthroplasty. INTRODUCTION: The risks of hip fracture and hip arthroplasty are influenced by factors including socioeconomic status, education, urbanization, latitude of residence, and physical activity. Farming is an occupation encompassing rural living and high level of physical activity. Therefore, we aimed to study the risk of hip fracture and risk of hip arthroplasty among farmers in Sweden. METHODS: We studied the risk of hip fracture, and hip arthroplasty due to primary osteoarthritis, in all men and women aged 35 years or more in Sweden between 1987 and 2002. Documented occupations were available in 3.5 million individuals, of whom 97,136 were farmers. The effects of age, sex, income, education, location of residence, and occupation on risk of hip fracture or hip arthroplasty were examined using a modification of Poisson regression. RESULTS: A total of 4027 farmers and 93,109 individuals with other occupations sustained a hip fracture, while 5349 farmers and 63,473 others underwent a hip arthroplasty. Risk of hip fracture was higher with greater age, lower income, lower education, higher latitude, and urban area for all men and women. Compared to all other occupations, male farmers had a 20% lower age-adjusted risk of hip fracture (hazard ratio (HR) 0.80, 95%CI 0.77-0.84), an effect that was not seen in female farmers (HR 0.96, 95% CI 0.91-1.01). Both male and female farmers had a higher age-adjusted risk for hip arthroplasty. CONCLUSIONS: Our results indicate that farming, representing an occupation with high physical activity, in men is associated with a lower risk of hip fracture but an increased risk of hip arthroplasty.

Middle-aged patients with an MRI-verified medial meniscal tear report symptoms commonly associated with knee osteoarthritis.

Background and purpose - No consensus exists on when to perform arthroscopic partial meniscectomy in patients with a degenerative meniscal tear. Since MRI and clinical tests are not accurate in detecting a symptomatic meniscal lesion, the patient's symptoms often play a large role when deciding when to perform surgery. We determined the prevalence and severity of self-reported knee symptoms in patients eligible for arthroscopic partial meniscectomy due to a degenerative meniscal tear. We investigated whether symptoms commonly considered to be related to meniscus injury were associated with early radiographic signs of knee osteoarthritis. Patients and methods - We included individual baseline items from the Knee injury and Osteoarthritis Outcome Score collected in 2 randomized controlled trials evaluating treatment for an MRI-verified degenerative medial meniscal tears in 199 patients aged 35-65 years. Each item was scored as no, mild, moderate, severe, extreme, and at least "mild" considering the symptoms present. Early radiographic signs of osteoarthritis, defined as a Kellgren and Lawrence grade of at least 1, were seen in 70 patients. Results - At least monthly knee pain, pain during stair walking and when twisting on the knee, and lack of confidence in knee was present in at least 80% of the patients. Median severity was at least moderate for knee pain, pain when twisting on the knee, pain walking on stairs, lack of confidence in knee, and clicking. Mechanical symptoms such as catching were rare. Early radiographic signs of osteoarthritis were associated with an increased risk of self-reported swelling, catching, and stiffness later in the day; the odds ratio was 2.4 (95% CI 1.2-4.9), 2.3 (1.2-4.3), and 2.3 (1.1-5.0), respectively. Interpretation - Middle-aged patients with a degenerative medial meniscus tear reported symptoms commonly associated with knee osteoarthritis. Frequent knee pain, presence of lack of confidence in the knee, and clicking did not distinguish those with a meniscal tear alone from those with early radiographic knee OA. Our findings support the notion that symptoms reported by those with a degenerative meniscal tear represent early signs of knee osteoarthritis.

The development of a short measure of physical function for knee OA KOOS-Physical Function Shortform (KOOS-PS) - an OARSI/OMERACT initiative.

OBJECTIVE: To develop a short measure of physical function for knee osteoarthritis (OA) using multi-national data from individuals with varying degrees of severity of knee OA. METHODS: Rasch analysis, based on the partial credit model, was conducted on Knee injury and Osteoarthritis Outcome Score and Western Ontario McMaster Universities' Osteoarthritis Index data from individuals with knee OA, ranging from community to pre-total knee replacement samples from five countries. Fit of the data to the Rasch model was evaluated by overall model fit and item-level fit statistics (chi(2), size of residual, F-test). Invariance across age, gender and country was evaluated. Unidimensionality was evaluated by factor analysis of residuals. The derived short measure was further tested for fit through re-analyses in individual sub-samples. A nomogram converting raw summed scores to Rasch-derived interval scores was developed. RESULTS: Thirteen data sets were included (n=2145), with an age range of 26-95 years, and a male/female ratio of 1:1.4. The final model included seven of the original 22 items. From easiest to most difficult, the items (logit) were as follows: rising from bed (1.366), putting on socks/stockings (1.109), rising from sitting (0.537), bending to the floor (0.433), twisting/pivoting on injured knee (-0.861), kneeling (-1.292) and squatting (-1.292). Sub-sample analyses confirmed findings. CONCLUSION: Based on the use of accepted Rasch-based measurement methods and the compliment of countries, languages and OA severity represented in this study, our seven item short measure of physical function for knee OA is likely generalizable and widely applicable. This measure has potential for use as the function component in an OA severity scoring system.