Association Between Metabolic Syndrome and Radiographic Hand Osteoarthritis: Data From a Community-Based Longitudinal Cohort Study

Hand osteoarthritis: A fresh look

Hand osteoarthritis (OA) has been the subject of numerous publications in recent years, particularly in the fields of imaging and therapeutics. The imaging studies revealed a good correlation between the presence of synovitis and/or subchondral edema and arthritic joint pain. Several randomized controlled trials (RCTs) have assessed the efficacy of biologics and conventional DMARDs in patients with symptomatic hand OA. No less than six RCTs have evaluated the symptomatic and, in some cases, structural efficacy of anti-IL-1, anti-TNF or anti-IL-6 drugs. Overall, the results of these trials were disappointing - none of them demonstrated superiority over placebo. There were also two negative trials with hydroxychloroquine. In the end, the only trial that was positive evaluated 10mg oral prednisone versus placebo for 6 weeks in patients with flares of hand OA and synovitis visible on ultrasound. While that trial confirms the role of inflammation in hand OA, it should obviously not encourage the long-term use of corticosteroids as a symptomatic treatment.

Metabolic syndrome is not associated with erosive hand osteoarthritis: a cross-sectional study using data from the PROCOAC cohort

To delineate the phenotype of erosive hand osteoarthritis (EHOA) in a Spanish population and assess its correlation with metabolic syndrome. We conducted a cross-sectional study using baseline data from the Prospective Cohort of Osteoarthritis from A Coruña (PROCOAC). Demographic and clinical variables, obtained through questionnaires, clinical examinations, and patient analytics, were compared among individuals with hand OA, with and without EHOA. We performed appropriate univariate and multivariate stepwise regression analyses using SPSS v28. Among 1039 subjects diagnosed with hand OA, 303 exhibited EHOA. Multivariate logistic regression analysis revealed associations with inflamed joints, nodular hand OA, and total AUSCAN. Furthermore, the association with a lower prevalence of knee OA remained significant. The influence of metabolic syndrome (MetS) on EHOA patients was analyzed by including MetS as a covariate in the model. It was observed that MetS does not significantly impact the presence of EHOA, maintaining the effect size of other factors. In conclusion, in the PROCOAC cohort, EHOA is associated with nodular hand OA, inflammatory hand OA, and a higher total AUSCAN. However, EHOA is linked to a lower prevalence of knee OA. Importantly, in our cohort, no relationship was found between EHOA and MetS.

Comorbidities in people with hand OA and their associations with pain severity and sensitization: Data from the longitudinal Nor-Hand study

Objective

To determine whether the comorbidity burden and co-existing comorbidities are cross-sectionally and/or longitudinally associated with pain and pain sensitization in a cohort study of people with hand OA.

Design

We examined whether comorbidity burden and individual comorbidities based on the self-administered Comorbidity Index (range: 0-42) at baseline were associated with pain outcomes at baseline and 3 years follow-up. Pain outcomes included hand and overall bodily pain (range: 0-10) as well as pressure pain thresholds at the tibialis anterior muscle (kg/cm²) and temporal summation (distal radioulnar joint) as measures of central pain sensitization. We performed linear regression analyses adjusted for age, sex, body mass index, physical exercise and education.

Results

We included 300 and 196 participants in cross-sectional and longitudinal analyses, respectively. Using baseline data, the burden of comorbidities was associated with greater pain in hands (beta ​= ​0.61, 95% CI 0.37, 0.85) and overall body (beta ​= ​0.60, 95% CI 0.37, 0.87). Similar strength of associations was found between comorbidity burden (baseline) and follow-up pain. Among the individual comorbidities, back pain and depression were associated with nearly one unit higher pain score in hands and overall body at both baseline and follow-up. Only back pain was related to lower pressure pain thresholds at follow up (beta ​= ​-0.24, 95% CI -0.50, -0.001).

Conclusion

People with hand OA and greater comorbidity burden, co-existing back pain or depression reported greater pain severity than their counterparts, also 3 years later. These results acknowledge the relevance of accounting for comorbidities in the pain experience in people with hand OA.

Fundamentals of OA. An initiative of Osteoarthritis and Cartilage. Obesity and metabolic factors in OA

OBJECTIVE

Obesity was once considered a risk factor for knee osteoarthritis (OA) primarily for biomechanical reasons. Here we provide an additional perspective by discussing how obesity also increases OA risk by altering metabolism and inflammation.

DESIGN

This narrative review is presented in four sections: 1) metabolic syndrome and OA, 2) metabolic biomarkers of OA, 3) evidence for dysregulated chondrocyte metabolism in OA, and 4) metabolic inflammation: joint tissue mediators and mechanisms.

RESULTS

Metabolic syndrome and its components are strongly associated with OA. However, evidence for a causal relationship is context dependent, varying by joint, gender, diagnostic criteria, and demographics, with additional environmental and genetic interactions yet to be fully defined. Importantly, some aspects of the etiology of obesity-induced OA appear to be distinct between men and women, especially regarding the role of adipose tissue. Metabolomic analyses of serum and synovial fluid have identified potential diagnostic biomarkers of knee OA and prognostic biomarkers of disease progression. Connecting these biomarkers to cellular pathophysiology will require future in vivo studies of joint tissue metabolism. Such studies will help reveal when a metabolic process or a metabolite itself is a causal factor in disease progression. Current evidence points towards impaired chondrocyte metabolic homeostasis and metabolic-immune dysregulation as likely factors connecting obesity to the increased risk of OA.

CONCLUSIONS

A deeper understanding of how obesity alters metabolic and inflammatory pathways in synovial joint tissues is expected to provide new therapeutic targets and an improved definition of "metabolic" and "obesity" OA phenotypes.

Erosive hand osteoarthritis: latest findings and outlook

Osteoarthritis (OA) most commonly affects knee joints, and the next most commonly affected sites are the hands and hips. Three distinct hand OA phenotypes have been described: erosive hand OA (EHOA), nodal hand OA - also known as non-erosive hand OA (non-EHOA) - and first carpometacarpal joint OA. EHOA predominantly affects women and is the most aggressive form of hand OA, characterized by a severe clinical onset and progression, leading to joint damage, disability and reduction of quality of life. Clinical signs of inflammation associated with EHOA include the acute onset of pain, swelling and redness. Moreover, EHOA is characterized by radiographic features such as central erosion, saw-tooth and gull-wing lesions and, rarely, ankylosis. The aim of this Review is to report the latest findings on epidemiology, clinical features, pathology and aetiopathogenesis, biomarkers, imaging modalities and treatments for EHOA. The ongoing development of new hand OA classification criteria should facilitate standardization between studies.

Association between hypertension and osteoarthritis: A systematic review and meta-analysis of observational studies

Objective

Literature examining the relationship between elevated blood pressure and osteoarthritis (OA) has yielded conflicting results. This study aimed to systematically review the relationship between hypertension and OA in both load-bearing and non-load-bearing joints.

Methods

A systematic literature search was performed on Embase, Emcare, MEDLINE and Ovid Nursing Database. The associations between hypertension and OA development in knees, hips and hands were analysed by calculating the odds ratio (OR).

Results

A total of 26 studies with 97,960 participants were included. The overall odds of having OA significantly increased in the people with hypertension compared to the normotensive ones (OR ​= ​1.60, 95%CI ​= ​1.33, 1.94). The association of hypertension with OA was detected in knee (OR ​= ​1.62, 95%CI ​= ​1.32, 1.98), not in hand (OR ​= ​1.19, 95%CI ​= ​0.92, 1.53). Moreover, there existed a stronger association of hypertension with radiographic knee OA (OR ​= ​1.89, 95%CI ​= ​1.40, 2.54) than symptomatic knee OA (OR ​= ​1.39, 95%CI ​= ​1.17, 1.65). The association between hypertension and radiographic knee OA remained statistically significant for the studies that adjusted for body mass index (BMI) (OR ​= ​1.42, 95%CI ​= ​1.13, 1.78), and was particularly strong in women (OR ​= ​2.27, 95%CI ​= ​1.17, 4.39).

Conclusion

A BMI-independent association between hypertension and radiographic knee OA existed with potential sex variation, which warrants further investigations into the underlying genetic, hormonal and environmental factors.

The translational potential of this article: Blood pressure has been reported to link with OA for years ago, however, its contribution to OA is still unclear and conflicted in different reports. This review indicated an intimate relationship between hypertension and structural damages of knee OA, rather than simply chronic joint pain, especially in women. This finding not only provides stronger support for further investigations into the causal risk factor, i.e. hypertension, of OA from tissue level to molecular level, but also putting forward a novel thinking in OA pathogenesis and its therapy strategies.

Orthopedic translation

This study further strengthen the association between hypertension and radiographic knee OA. It points in a vascular aetiology hypothesis of OA. It might open up a new avenue for repositioning anti-hypertensive medications for osteoarthritis treatment.

Mediation of the association between obesity and osteoarthritis by blood pressure, vessel wall stiffness and subclinical atherosclerosis

Objective

We investigated the role of blood pressure, vessel wall stiffness [pulse wave velocity (PWV)] and subclinical atherosclerosis markers [carotid intima-media thickness (cIMT), popliteal vessel wall thickness (pVWT)] as mediators of the association of obesity with OA.

Methods

We used cross-sectional data from a subset of the population-based NEO study (n = 6334). We classified clinical hand and knee OA by the ACR criteria, and structural knee OA, effusion and bone marrow lesions on MRI (n = 1285). cIMT was assessed with ultrasonography. pVWT was estimated on knee MRI (n = 1285), and PWV by abdominal velocity-encoded MRIs (n = 2580), in subpopulations. Associations between BMI and OA were assessed with logistic regression analyses, adjusted for age, sex and education. Blood pressure, cIMT, pVWT and PWV were added to the model to estimate mediation.

Results

The population consisted of 55% women, with a mean (s.d.) age of 56(6) years. Clinical hand OA was present in 8%, clinical knee OA in 10%, and structural knee OA in 12% of participants. BMI was positively associated with all OA outcomes. cIMT partially mediated the association of BMI with clinical hand OA [10.6 (6.2; 30.5)%], structural knee OA [3.1 (1.9; 7.3)%] and effusion [10.8 (6.0; 37.6)%]. Diastolic blood pressure [2.1 (1.6; 3.0)%] minimally mediated the association between BMI and clinical knee OA. PWV and pVWT did not mediate the association between BMI and OA.

Conclusions

cIMT and diastolic blood pressure minimally mediated the association of BMI with OA. This suggests that such mediation is trivial in the middle-aged population.

Metabolic Syndrome and Osteoarthritis Distribution in the Hand Joints: A Propensity Score Matching Analysis From the Osteoarthritis Initiative

OBJECTIVE

To investigate the metabolic syndrome (MetS) association with radiographic and symptomatic hand osteoarthritis (HOA).

METHODS

Using 1:2 propensity score matching for relevant confounders, we included 2509 participants (896 MetS positive and 1613 MetS negative) from the Osteoarthritis Initiative dataset. MetS and its components, according to the International Diabetes Federation criteria, were extracted from baseline data, and included hypertension, abdominal obesity, dyslipidemia, and diabetes. We scored distinct hand joints based on the modified Kellgren-Lawrence (mKL) grade of baseline radiographs, with HOA defined as mKL ≥ 2. In the cross-sectional analysis, we investigated the association between MetS and its components with radiographic HOA and the presence of nodal and erosive HOA phenotypes using regression models. In the longitudinal analysis, we performed Cox regression analysis for hand pain incidence in follow-up visits.

RESULTS

MetS was associated with higher odds of radiographic HOA, including the number of joints with OA (OR 1.32, 95% CI 1.08-1.62), the sum of joints mKLs (OR 2.42, 95% CI 1.24-4.71), mainly in distal interphalangeal joints (DIPs) and proximal interphalangeal joints (PIPs; OR 1.52, 95% CI 1.08-2.14 and OR 1.38, 95% CI 1.09-1.75, respectively), but not metacarpophalangeal (MCP) and first carpometacarpal (CMC1) joints. Hand pain incidence during follow-up was higher with MetS presence (HR 1.25, 95% CI 1.07-1.47). The erosive HOA phenotype and joints' nodal involvement were more frequent with MetS (OR 1.40, 95% CI 1.01-1.97 and OR 1.28, 95% CI 1.02-1.60, respectively).

CONCLUSION

MetS, a potentially modifiable risk factor, is associated with radiographic DIP and PIP OA and longitudinal hand pain incidence while sparing MCPs and CMC1s. Nodal and erosive HOA phenotypes are associated with MetS, suggestive of possible distinct pathophysiology.

Towards sex-specific osteoarthritis risk models: evaluation of risk factors for knee osteoarthritis in males and females

Objectives

The aim of this study was to identify sex-specific prevalence and strength of risk factors for the incidence of radiographic knee OA (incRKOA).

Methods

Our study population consisted of 10 958 Rotterdam Study participants free of knee OA in one or both knees at baseline. One thousand and sixty-four participants developed RKOA after a median follow-up time of 9.6 years. We estimated the association between each available risk factor and incRKOA using sex stratified multivariate regression models with generalized estimating equations. Subsequently, we statistically tested sex differences between risk estimates and calculated the population attributable fractions (PAFs) for modifiable risk factors.

Results

The prevalence of the investigated risk factors was, in general, higher in women compared with men, except that alcohol intake and smoking were higher in men and high BMI showed equal prevalence. We found significantly different risk estimates between men and women: high level of physical activity [relative risk (RR) 1.76 (95% CI: 1.29–2.40)] or a Kellgren and Lawrence score 1 at baseline [RR 5.48 (95% CI: 4.51–6.65)] was higher in men. Among borderline significantly different risk estimates was BMI ≥27, associated with higher risk for incRKOA in women [RR 2.00 (95% CI: 1.74–2.31)]. The PAF for higher BMI was 25.6% in women and 19.3% in men.

Conclusion

We found sex-specific differences in both presence and relative risk of several risk factors for incRKOA. Especially BMI, a modifiable risk factor, impacts women more strongly than men. These risk factors can be used in the development of personalized prevention strategies and in building sex-specific prediction tools to identify high risk profile patients.

Association between statin use and incidence or progression of osteoarthritis: meta-analysis of observational studies

OBJECTIVE

The objective of the study was to determine whether statin use could reduce the risk of the incidence or progression of osteoarthritis (OA).

METHODS

The PubMed, Embase, and Cochrane databases were systematically searched for observational studies on the association between statin use and OA. ORs and 95% CIs were directly retrieved or calculated. The Newcastle-Ottawa quality assessment scale was used for study quality assessment. Subgroup analysis, sensitivity analysis, and publication bias were conducted using Stata software.

RESULTS

A total of 11 studies (679807 participants) were identified from the systematic literature search. No significant association between statin use and incidence (OR = 1.010; 95% CI: 0.968 to 1.055; P = 0.638) or progression (OR = 1.076; 95% CI: 0.824 to 1.405; P = 0.589) of OA was found in our meta-analysis. The meta-analysis according to the symptomatic or radiological OA also found no significant association between statin use and OA. The subgroup analysis showed that atorvastatin (OR = 0.953; 95% CI: 0.911 to 0.998; P = 0.041) and rosuvastatin (OR = 1.180; 95% CI: 1.122 to 1.241; P < 0.0001) had opposite effects on OA. The results of the analysis according to the joint site, interval, and statin dose were all not significant.

CONCLUSIONS

Statin use may not be associated with a lower risk of incidence and progression of OA, regardless of joint site. The opposite effects of atorvastatin and rosuvastatin were detected in OA.

Identifying effector molecules, cells, and cytokines of innate immunity in OA

Inflammatory changes are observed in affected joints of osteoarthritis (OA) patients and are thought to be involved in the pathology that develops along OA progression. This narrative review provides an overview of the various cell types that are present in the joint during OA and which alarmins, cytokines, chemokines, growth factors, and other mediators they produce. Moreover, the involvement of more systemic processes like inflammaging and its associated cellular senescence in the context of OA are discussed.

Association between metabolic syndrome and hip osteoarthritis in middle-aged men and women from the general population

OBJECTIVE

To investigate the impact of metabolic syndrome and its components on osteoarthritis of the hip joints compared to a healthy cohort in the KORA MRI-study.

METHODS

Randomly selected men and women from the general population were classified as having metabolic syndrome, defined as presence of central obesity plus two of the following four components: elevated blood pressure (BP), elevated fasting glucose, elevated triglycerides (TG) and low HDL-cholesterol (HDL-c), or as controls without metabolic syndrome. Therefore, each subject underwent detailed assessment of waist circumference as well as fasting glucose, systolic and diastolic BP, TG, and HDL-c concentrations as well as a full-body MR scan. MR measurements were performed on a 3 Tesla scanner (Magnetom Skyra, Siemens) including a dual-echo Dixon and a T2 SS-FSE sequence for anatomical structures. In order to quantify osteoarthritis of the hip, assessment was performed by two independent, experienced radiologists for joint gap narrowing, osteophytic lipping and subchondral changes (e.g. sclerosis, pseudocysts). Associations between metabolic syndrome components and hip degeneration were estimated by logistic regression models providing odds ratios.

RESULTS

Among 354 included participants (mean age: 56.1 ± 9.2 years; 55.4% male), 119 (34%) had metabolic syndrome, while 235 (66%) were part of the control group. Except for elevated blood glucose (p = 0.02), none of the metabolic syndromes' component was independently associated with osteoarthritis. Multivariable adjusted ORs for osteoarthritis of the right hip were 1.00 (95% CI 0.98;1.03), 1.00 (95% CI 0.99;1.00), 1.01 (95% CI 0.99;1.03), 1.00 (95% CI 0.97;1.04) and 1.01 (95% CI 0.96;1.06), and for the left hip 1.00 (95% CI 0.98;1.03), 1.00 (95% CI 1.00;1.01), 1.01 (95% CI 0.99;1.03), 0.99 (95% CI 0.96;1.02) and 1.04 (95% CI 0.99;1.09) for waist circumference, triglyceride, HDL-c and systolic and diastolic BP, respectively. Blood glucose was a borderline non-dependent factor for osteoarthritis of the right hip (OR: 1.02 (95% CI 1.0;1.04); p = 0.05). Furthermore, the compound metabolic syndrome was not significantly associated (OR left hip: 1.53 (95% CI 0.8;2.92), p = 0.20; OR right hip: 1.33 (95% CI 0.72;2.45), p = 0.37) with osteoarthritis of the hip joint. Age as well as gender (left hip) were the only parameters in univariate and multivariate analysis to be significantly associated with osteoarthritis of the hip joint.

CONCLUSION

The compound metabolic syndrome showed no association with osteoarthritis of the hip joint. Age was the only parameter to be dependently and independently associated to osteoarthritis of both hip joints, while elevated blood glucose was independently associated with degeneration of the right hip joint.

An update on the association between metabolic syndrome and osteoarthritis and on the potential role of leptin in osteoarthritis

Metabolic syndrome (MetS) has been associated with osteoarthritis (OA). Leptin, which is one of the markers of MetS, has been associated with OA pathophysiology. This study aimed to provide an update on the association between MetS and OA and on the potential role of leptin in OA. In this review, we summarized the current knowledge of the association between MetS and OA and updated the evidence on the potential role of leptin in OA. Clinical studies have investigated the epidemiologic association between MetS or its components and OA. Results suggested strong epidemiologic associations between MetS and OA, especially in the Asian population. Animal studies also indicated that metabolic dysregulation may lead to OA pathogenesis. The systemic role of MetS in OA pathophysiology is associated with obesity-related inflammation, the beneficial role of n-3 polyunsaturated fatty acids and deleterious role of cholesterol, physical inactivity, hypertension-induced subchondral ischemia, dyslipidemia-induced ectopic lipid deposition in chondrocytes, hyperglycemia-induced local effects of oxidative stress and advanced glycation end-products, low-grade systemic inflammation, and obesity-related adipokines by inducing the expression of proinflammtory factors. Leptin levels in serum/plasma and synovial fluid were associated with joint pain, radiographic progression, bone formation biomarkers, cartilage volume, knee OA incidence, and total joint arthroplasty in OA patients. Elevated leptin expression and increased effect of leptin on infrapatellar fat pad, synovium, articular cartilage, and bone were also involved in the pathogenesis of OA. Current knowledge indicates a convincing epidemiologic association between MetS and OA, especially in the Asian population. Animal studies have also shown that metabolic dysregulation may lead to OA pathogenesis. Accumulating evidence suggests that leptin may play a potential role in OA pathogenesis. Therefore, leptin and its receptor may be an emerging target for intervention in metabolic-associated OA.

Effects of Comorbid Cardiovascular Disease and Diabetes on Hand Osteoarthritis, Pain, and Functional State Transitions: The Johnston County Osteoarthritis Project

OBJECTIVE

The purpose of this study is to examine the course of hand osteoarthritis (HOA) and its relationship with cardiovascular disease (CVD) and diabetes (DM).

METHODS

Data were collected at 3 timepoints from 845 Johnston County Osteoarthritis Project participants (two-thirds women, one-third African Americans, mean age 60 yrs) with and without HOA, CVD, or DM. A diagnosis of radiographic HOA (rHOA) required a Kellgren-Lawrence severity grade of ≥ 2 in at least 3 joints in each hand. A 4-state progressive model included transitions based on rHOA and pain or function as defined using the Australian/Canadian HOA Index (AUSCAN). Markov multistate models estimated HR (aHR) and 95% CI for associations between DM or CVD and specific state transitions, adjusting for baseline and time-varying covariates.

RESULTS

Participants with DM (vs those without DM) were more likely to experience worsening pain with rHOA. Individuals who had or developed CVD (vs those who did not) were significantly less likely to experience symptomatic improvement, regardless of rHOA status. Those with DM or CVD (vs those without these comorbidities) were less likely to experience improvement in function, although this was statistically significant only for those with DM and no rHOA.

CONCLUSION

Overall, having or developing DM and/or CVD reduced the likelihood of symptomatic and functional improvement over time, suggesting an effect of comorbid CVD and DM on the clinical and radiographic course of HOA. Additional studies are needed to confirm these findings.

Bidirectional association between metabolic syndrome and osteoarthritis: a meta-analysis of observational studies

BACKGROUND

Emerging observational studies suggest an association between metabolic syndrome (MetS) and osteoarthritis (OA). This meta-analysis was conducted to examine whether or not there is a bidirectional relationship between MetS and OA.

METHODS

The PubMed and Embase databases were searched from their inception to October 2019. We selected studies according to predefined criteria. Random effects were selected to calculate two sets of pooled risk estimates: MetS predicting OA and OA predicting MetS.

RESULTS

A total of seven cross-sectional studies and four cohort studies met the criteria for MetS predicting the onset of OA. Another six cross-sectional studies and one cohort study met the criteria for OA predicting the onset of MetS. The pooled odds risk (OR) for OA incidences associated with baseline MetS was 1.45 (95% CI 1.27-1.66). The OR for MetS incidences associated with baseline OA was 1.90 (95% CI 1.11-3.27). In an overall analysis, we found that MetS was associated with prevalent OA in both cross-sectional studies (OR = 1.32, 95% CI 1.21-1.44) and cohort studies (OR = 1.76, 95% CI 1.29-2.42). No indication of heterogeneity was found in the cross-sectional studies (p = 0.395, I² = 4.8%), whereas substantial heterogeneity was detected in the cohort studies (p = 0.000, I² = 79.3%).

CONCLUSION

Meta-analysis indicated a bidirectional association between MetS and OA. We advise that patients with MetS should monitor their OA status early and carefully, and vice versa.

The role of leptin and adiponectin as mediators in the relationship between adiposity and hand and knee osteoarthritis

OBJECTIVES

To investigate associations of leptin and adiponectin levels with knee and hand osteoarthritis, and explore whether these mediate the association between adiposity and osteoarthritis.

METHODS

This is a cross-sectional analysis of baseline data from the population-based Netherlands Epidemiology of Obesity study. Adiposity was assessed with body mass index (BMI) and percentage total body fat (%TBF). Osteoarthritis, defined as hand or knee osteoarthritis, was determined using American College of Rheumatology criteria. Fasting serum adipokine levels were measured using immunoassays. Associations between adiposity and osteoarthritis were examined with logistic regression, adjusted for age, sex, ethnicity and education, and additionally for leptin and adiponectin as potential mediators.

RESULTS

In 6408 participants (56% women, median age 56 years), prevalence of osteoarthritis was 22% (10% isolated knee and 8% isolated hand osteoarthritis). Leptin levels were positively associated with osteoarthritis, while adiponectin levels were not. Leptin partially mediated the association of adiposity with osteoarthritis (OR 1.40 (95%CI 1.30; 1.52) attenuated to 1.38 (1.24; 1.54) per 5 units BMI and OR 1.25 (1.17; 1.35) to 1.20 (1.10; 1.32) per 5 units %TBF, representing 4% and 17% mediation, respectively). Larger proportion mediation by leptin was found in knee (13%/27%) than in hand osteoarthritis (9%/18%). Sex-stratified analyses generally showed stronger associations between adiposity, leptin and osteoarthritis in women than in men.

CONCLUSIONS

Serum leptin levels were associated with osteoarthritis, and partially mediated the association between adiposity and osteoarthritis, while adiponectin levels were not associated with osteoarthritis. These findings provide evidence for systemic effects of adipose tissue in osteoarthritis.

Association between metabolic syndrome and knee structural change on MRI

Objective

To examine the association of metabolic syndrome (MetS) and its components with knee cartilage volume loss and bone marrow lesion (BML) change.

Methods

Longitudinal data on 435 participants from a population-based cohort study were analysed. Blood pressure, glucose, triglycerides and high-density lipoprotein (HDL) were collected. MetS was defined based on the National Cholesterol Education Program–Adult Treatment Panel III criteria. MRI of the right knee was performed to measure cartilage volume and BML. Radiographic knee OA was assessed by X-ray and graded using the Altman atlas for osteophytes and joint space narrowing.

Results

Thirty-two percent of participants had MetS and 60% had radiographic knee OA. In multivariable analysis, the following were independently associated with medial tibial cartilage volume loss: MetS, β = −0.30%; central obesity, β = −0.26%; and low HDL, β = −0.25% per annum. MetS, hypertriglyceridaemia and low HDL were also associated with higher risk of BML size increase in the medial compartment (MetS: relative risk 1.72, 95% CI 1.22, 2.43; hypertriglyceridaemia: relative risk 1.43, 95% CI 1.01, 2.02; low HDL: relative risk 1.67, 95% CI 1.18, 2.36). After further adjustment for central obesity or BMI, MetS and low HDL remained statistically significant for medial tibial cartilage volume loss and BML size increase. The number of components of MetS correlated with greater cartilage volume loss and BML size increase (both P for trend <0.05). There were no statistically significant associations in the lateral compartment.

Conclusion

MetS and low HDL are associated with medial compartment cartilage volume loss and BML size increase, suggesting that targeting these factors has the potential to prevent or slow knee structural change.

What Is the Evidence to Support the Association Between Metabolic Syndrome and Osteoarthritis? A Systematic Review

OBJECTIVE

There is conflicting evidence on the association between metabolic syndrome (MetS) with the risk of osteoarthritis (OA). We aimed to systematically summarize the empirical evidence and discuss challenges in research methodologies in addressing this question.

METHODS

We performed a systematic literature review based on PubMed, Embase, Web of Science, and the Cochrane Database of Systematic Reviews on published epidemiologic studies that examined the association between MetS and the risk of OA. We included cross-sectional studies, case-control studies, and cohort studies with appropriate covariate adjustments. We extracted information on prevalence, incidence, crude and adjusted effect estimates, and the 95% confidence intervals from the articles, or this information was provided by the authors. We listed the main methodologic issues existing in current literature and provided recommendations for future research on this topic.

RESULTS

We identified 7 eligible studies on knee OA, 3 on hip OA, and 3 on hand OA. In studies that adjusted for body mass index or weight, MetS was not significantly associated with the risk of knee OA. No significant associations were reported for hip OA. For hand OA, the data were sparse and insufficient to reach a conclusion. Studies were mostly cross-sectional, exposure included only 1 time measurement, few studies had incident outcomes, and covariate adjustment was often insufficient.

CONCLUSION

Our review was unable to reach a definitive conclusion due to insufficient data, although the data suggest that knee and hip OA are not associated with MetS. Future longitudinal studies with incident OA cases, repeated measurement of MetS, and appropriate covariate adjustment are needed.

Metabolic risk factors and the incidence and progression of radiographic hand osteoarthritis: a population-based cohort study

OBJECTIVE

To determine whether selected metabolic factors are associated with greater amounts of radiographic hand osteoarthritis (OA) incidence and progression.

METHODS

The study identified 706 adults, aged 50-69 years, with hand pain and hand radiographs at baseline, from two population-based cohorts. Metabolic factors (body mass index, hypertension, dyslipidaemia, and diabetes) were ascertained at baseline by direct measurement and medical records. Analyses were undertaken following multiple imputation of missing data, and in complete cases (sensitivity analyses). Multivariable regression models estimated associations between metabolic factors and two measures of radiographic change at 7 years for all participants, individuals free of baseline radiographic OA, and in baseline hand OA subsets. Estimates were adjusted for baseline values and other covariates.

RESULTS

The most consistent and strong associations observed were between the presence of diabetes and the amount of radiographic progression in individuals with nodal OA [adjusted mean differences in Kellgren-Lawrence summed score of 4.50 (-0.26, 9.25)], generalized OA [3.27 (-2.89, 9.42)], and erosive OA [3.05 (-13.56, 19.67)]. The remaining associations were generally weak or inconsistent, although numbers were limited for analyses of incident radiographic OA and erosive OA in particular.

CONCLUSION

Overall metabolic risk factors were not independently or collectively associated with greater amounts of radiographic hand OA incidence or progression over 7 years, but diabetes was associated with radiographic progression in nodal, and possibly generalized and erosive OA. Diabetes has previously been associated with prevalent but not incident hand OA. Further investigation in hand OA subsets using objective measures accounting for disease duration and control is warranted.

The interrelation of osteoarthritis and diabetes mellitus: considering the potential role of interleukin-10 and in vitro models for further analysis

INTRODUCTION

Today, not only the existence of an interrelation between obesity/adipositas and osteoarthritis (OA) but also the association of OA and diabetes mellitus (DM) are widely recognized. Nevertheless, shared influence factors facilitating OA development in DM patients still remain speculative up until now. To supplement the analysis of clinical data, appropriate in vitro models could help to identify shared pathogenetic pathways. Informative in vitro studies could later be complemented by in vivo data obtained from suitable animal models.

MATERIALS AND METHODS

Therefore, this detailed review of available literature was undertaken to discuss and compare the results of currently published in vitro studies focusing on the interrelation between OA, the metabolic syndrome and DM and to propose models to further study the molecular pathways.

RESULTS

The survey of literature presented here supports the hypothesis that the pathogenesis of OA in DM is based on imbalanced molecular pathways with a putative crucial role of antiinflammatory cytokines such as IL-10.

CONCLUSION

Future development of versatile micro-scaled in vitro models such as combining DM and OA on chip could allow the identification of common pathogenetic pathways and might help to develop novel therapeutic strategies.