Search

Background Obesity is an important risk factor for knee osteoarthritis (OA), Weight loss can reduce the symptoms of knee OA. No prospective studies assessing the impact of weight loss on knee cartilage structure and composition have been performed. Objectives To assess the impact of weight loss on knee cartilage thickness and composition. Methods 111 obese adults were recruited from either laparoscopic adjustable gastric banding or exercise and diet weight loss programmes from two tertiary centres. MRI was performed at baseline and 12-month follow-up to assess cartilage thickness. 78 eligible subjects also underwent delayed gadolinium-enhanced MRI of cartilage (dGEMRIC), an estimate of proteoglycan content. The associations between cartilage outcomes (cartilage thickness and dGEMRIC index) and weight loss were adjusted for age, gender, body mass index (BMI) and presence of clinical knee OA. Results Mean age was 51.7±11.8 years and mean BMI was 36.6±5.8 kg/m2; 32% had clinical knee OA. Mean weight loss was 9.3±11.9%. Percentage weight loss was negatively associated with cartilage thickness loss in the medial femoral compartment in multiple regression analysis (β=0.006, r²=0.19, p=0.029). This association was not detected in the lateral compartment (r²=0.12, p=0.745). Percentage weight loss was associated with an increase in medial dGEMRIC in multiple regression analysis (β=3.9, r²=0.26; p=0.008) but not the lateral compartment (r²=0.14, p=0.34). For every 10% weight loss there was a gain in the medial dGEMRIC index of 39 ms (r²=0.28; p=0.014). The lowest weight loss cut-off associated with reduced medial femoral cartilage thickness loss and improved medial dGEMRIC index was 7%. Conclusions Weight loss is associated with improvements in the quality (increased proteoglycan content) and quantity (reduced cartilage thickness losses) of medial articular cartilage. This was not observed in the lateral compartment. This could ultimately lead to a reduced need for total joint replacements and is thus a finding with important public health implications. [ABSTRACT FROM AUTHOR]

Objective: To determine if the dietary supplements, glucosamine and/or chondroitin, result in reduced joint space narrowing (JSN) and pain among people with symptomatic knee osteoarthritis., Methods: A double-blind randomised placebo-controlled clinical trial with 2-year follow-up. 605 participants, aged 45-75 years, reporting chronic knee pain and with evidence of medial tibio-femoral compartment narrowing (but retaining >2 mm medial joint space width) were randomised to once daily: glucosamine sulfate 1500 mg (n=152), chondroitin sulfate 800 mg (n=151), both dietary supplements (n=151) or matching placebo capsules (n=151). JSN (mm) over 2 years was measured from digitised knee radiographs. Maximum knee pain (0-10) was self-reported in a participant diary for 7 days every 2 months over 1 year., Results: After adjusting for factors associated with structural disease progression (gender, body mass index (BMI), baseline structural disease severity and Heberden's nodes), allocation to the dietary supplement combination (glucosamine-chondroitin) resulted in a statistically significant (p=0.046) reduction of 2-year JSN compared to placebo: mean difference 0.10 mm (95% CI 0.002 mm to 0.20 mm); no significant structural effect for the single treatment allocations was detected. All four allocation groups demonstrated reduced knee pain over the first year, but no significant between-group differences (p=0.93) were detected. 34 (6%) participants reported possibly-related adverse medical events over the 2-year follow-up period., Conclusions: Allocation to the glucosamine-chondroitin combination resulted in a statistically significant reduction in JSN at 2 years. While all allocation groups demonstrated reduced knee pain over the study period, none of the treatment allocation groups demonstrated significant symptomatic benefit above placebo., Trial Registration Clinicaltrialsgov Identifier: NCT00513422; http://www.clinicaltrials.gov., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Objective: To estimate the global burden of hip and knee osteoarthritis (OA) as part of the Global Burden of Disease 2010 study and to explore how the burden of hip and knee OA compares with other conditions., Methods: Systematic reviews were conducted to source age-specific and sex-specific epidemiological data for hip and knee OA prevalence, incidence and mortality risk. The prevalence and incidence of symptomatic, radiographic and self-reported hip or knee OA were included. Three levels of severity were defined to derive disability weights (DWs) and severity distribution (proportion with mild, moderate and severe OA). The prevalence by country and region was multiplied by the severity distribution and the appropriate disability weight to calculate years of life lived with disability (YLDs). As there are no deaths directly attributed to OA, YLDs equate disability-adjusted life years (DALYs)., Results: Globally, of the 291 conditions, hip and knee OA was ranked as the 11th highest contributor to global disability and 38th highest in DALYs. The global age-standardised prevalence of knee OA was 3.8% (95% uncertainty interval (UI) 3.6% to 4.1%) and hip OA was 0.85% (95% UI 0.74% to 1.02%), with no discernible change from 1990 to 2010. Prevalence was higher in females than males. YLDs for hip and knee OA increased from 10.5 million in 1990 (0.42% of total DALYs) to 17.1 million in 2010 (0.69% of total DALYs)., Conclusions: Hip and knee OA is one of the leading causes of global disability. Methodological issues within this study make it highly likely that the real burden of OA has been underestimated. With the aging and increasing obesity of the world's population, health professions need to prepare for a large increase in the demand for health services to treat hip and knee OA., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

The objective of this paper is to provide an overview of methods used for estimating the burden from musculoskeletal (MSK) conditions in the Global Burden of Diseases 2010 study. It should be read in conjunction with the disease-specific MSK papers published in Annals of Rheumatic Diseases. Burden estimates (disability-adjusted life years (DALYs)) were made for five specific MSK conditions: hip and/or knee osteoarthritis (OA), low back pain (LBP), rheumatoid arthritis (RA), gout and neck pain, and an 'other MSK conditions' category. For each condition, the main disabling sequelae were identified and disability weights (DW) were derived based on short lay descriptions. Mortality (years of life lost (YLLs)) was estimated for RA and the rest category of 'other MSK', which includes a wide range of conditions such as systemic lupus erythematosus, other autoimmune diseases and osteomyelitis. A series of systematic reviews were conducted to determine the prevalence, incidence, remission, duration and mortality risk of each condition. A Bayesian meta-regression method was used to pool available data and to predict prevalence values for regions with no or scarce data. The DWs were applied to prevalence values for 1990, 2005 and 2010 to derive years lived with disability. These were added to YLLs to quantify overall burden (DALYs) for each condition. To estimate the burden of MSK disease arising from risk factors, population attributable fractions were determined for bone mineral density as a risk factor for fractures, the occupational risk of LBP and elevated body mass index as a risk factor for LBP and OA. Burden of Disease studies provide pivotal guidance for governments when determining health priority areas and allocating resources. Rigorous methods were used to derive the increasing global burden of MSK conditions.