Increased prevalence and severity of radiographic hand osteoarthritis in patients with HIV-1 infection associated with metabolic syndrome: data from the cross-sectional METAFIB-OA study

The role of obesity and adipose tissue dysfunction in osteoarthritis pain

Obesity has a pivotal and multifaceted role in pain associated with osteoarthritis (OA), extending beyond the mechanistic influence of BMI. It exerts its effects both directly and indirectly through various modifiable risk factors associated with OA-related pain. Adipose tissue dysfunction is highly involved in OA-related pain through local and systemic inflammation, immune dysfunction, and the production of pro-inflammatory cytokines and adipokines. Adipose tissue dysfunction is intricately connected with metabolic syndrome, which independently exerts specific effects on OA-related pain, distinct from its association with BMI. The interplay among obesity, adipose tissue dysfunction and metabolic syndrome influences OA-related pain through diverse pain mechanisms, including nociceptive pain, peripheral sensitization and central sensitization. These complex interactions contribute to the heightened pain experience observed in individuals with OA and obesity. In addition, pain management strategies are less efficient in individuals with obesity. Importantly, therapeutic interventions targeting obesity and metabolic syndrome hold promise in managing OA-related pain. A deeper understanding of the intricate relationship between obesity, metabolic syndrome and OA-related pain is crucial and could have important implications for improving pain management and developing innovative therapeutic options in OA.

Diabetes and Osteoarthritis: Exploring the Interactions and Therapeutic Implications of Insulin, Metformin, and GLP-1-Based Interventions

Diabetes mellitus (DM) and osteoarthritis (OA) are prevalent chronic conditions with shared pathophysiological links, including inflammation and metabolic dysregulation. This study investigates the potential impact of insulin, metformin, and GLP-1-based therapies on OA progression. Methods involved a literature review of clinical trials and mechanistic studies exploring the effects of these medications on OA outcomes. Results indicate that insulin, beyond its role in glycemic control, may modulate inflammatory pathways relevant to OA, potentially influencing joint health. Metformin, recognized for its anti-inflammatory properties via AMPK activation, shows promise in mitigating OA progression by preserving cartilage integrity and reducing inflammatory markers. GLP-1-based therapies, known for enhancing insulin secretion and improving metabolic profiles in DM, also exhibit anti-inflammatory effects that may benefit OA by suppressing cytokine-mediated joint inflammation and supporting cartilage repair mechanisms. Conclusions suggest that these medications, while primarily indicated for diabetes management, hold therapeutic potential in OA by targeting common underlying mechanisms. Further clinical trials are warranted to validate these findings and explore optimal therapeutic strategies for managing both DM and OA comorbidities effectively.

The impact of asymptomatic human immunodeficiency virus (HIV)-positive disease status on inpatient complications following total joint arthroplasty: a propensity score-matched analysis

PURPOSE

The number of patients with asymptomatic human immunodeficiency virus (AHIV) is increasing as the efficacy of antiretroviral therapy improves. While there is research on operative risks associated with having HIV, there is a lack of literature describing the impact of well-controlled HIV on postoperative complications. This study seeks to elucidate the impact of AHIV on postoperative outcomes after total hip (THA) and knee (TKA) arthroplasty.

METHODS

The Nationwide Inpatient Sample was retrospectively reviewed for patients undergoing TKA and THA from 2005 to 2013. Subjects were subdivided into those with AHIV and those without HIV (non-HIV). Patient demographics, hospital-related parameters, and postoperative complications were all collected. One-to-one propensity score-matching, Chi-square analysis, and multivariate logistical regressions were performed to compare both cohorts.

RESULTS

There were no significant differences between AHIV and non-HIV patients undergoing TKA or THA in terms of sex, age, insurance status, or total costs (all, p ≥ 0.081). AHIV patients had longer lengths of stay (4.0 days) than non-HIV patients after both TKA (3.3 days) and THA (3.1 days) (p ≤ 0.011). Both TKA groups had similar postoperative complication rates (p > 0.081). AHIV patients undergoing THA exhibited an increased rate of overall surgical complications compared non-HIV patients (0 vs. 4.5%, p = 0.043). AHIV was not associated with increased complications following both procedures.

CONCLUSION

Despite lengthier hospital stays among AHIV patients, baseline AHIV was not associated with adverse outcomes following TKA and THA. This adds to the literature and warrants further research into the impact of asymptomatic, well-controlled HIV infection on postoperative outcomes following total joint arthroplasty.

The physiological metabolite α-ketoglutarate ameliorates osteoarthritis by regulating mitophagy and oxidative stress

Osteoarthritis (OA) is an age-related metabolic disease. Low-grade inflammation and oxidative stress are the last common pathway of OA. α-ketoglutarate (α-KG) is an essential physiological metabolite from the mitochondrial tricarboxylic acid (TCA) cycle, with multiple functions, including anti-inflammation and antioxidation, and exhibits decreased serum levels with age. Herein, we aimed to investigate the effect and mechanism of α-KG on OA. We first quantified the α-KG levels in human cartilage tissue and osteoarthritic chondrocytes induced by IL-1β. Besides, IL-1β-induced osteoarthritic chondrocytes were treated with different concentrations of α-KG. Chondrocyte proliferation and apoptosis, synthesis and degradation of extracellular matrix, and inflammation mediators were analyzed. RNA sequencing was used to explore the mechanism of α-KG, and mitophagy and oxidative stress levels were further detected. These results were verified in an anterior cruciate ligament transection (ACLT) induced age-related OA rat model. We found that α-KG content decreased by 31.32% in damaged medial cartilage than in normal lateral cartilage and by 36.85% in IL-1β-induced human osteoarthritic chondrocytes compared to control. α-KG supplementation reversed IL-1β-induced chondrocyte proliferation inhibition and apoptosis, increased the transcriptomic and proteinic expression of ACAN and COL2A1 in vivo and in vitro, but inhibited the expression of MMP13, ADAMTS5, IL-6, and TNF-α. In mechanism, α-KG promoted mitophagy and inhibited ROS generation, and these effects could be prevented by Mdivi-1 (a mitophagy inhibitor). Overall, α-KG content decreased in human OA cartilage and IL-1β-induced osteoarthritic chondrocytes. Moreover, α-KG supplementation could alleviate osteoarthritic phenotype by regulating mitophagy and oxidative stress, suggesting its potential as a therapeutic target to ameliorate OA.

Obesity promotes lipid accumulation in mouse cartilage-A potential role of acetyl-CoA carboxylase (ACC) mediated chondrocyte de novo lipogenesis

Obesity promotes the development of osteoarthritis (OA). It is also well-established that obesity leads to excessive lipid deposition in nonadipose tissues, which often induces lipotoxicity. The objective of this study was to investigate changes in the levels of various lipids in mouse cartilage in the context of obesity and determine if chondrocyte de novo lipogenesis is altered. We used Oil Red O to determine the accumulation of lipid droplets in cartilage from mice fed high-fat diet (HFD) or low-fat diet (LFD). We further used mass spectrometry-based lipidomic analyses to quantify levels of different lipid species. Expression of genes involving in fatty acid (FA) uptake, synthesis, elongation, and desaturation were examined using quantitative polymerase chain reaction. To further study the potential mechanisms, we cultured primary mouse chondrocytes under high-glucose and high-insulin conditions to mimic the local microenvironment associated with obesity and subsequently examined the abundance of cellular lipid droplets. The acetyl-CoA carboxylase (ACC) inhibitor, ND-630, was added to the culture medium to examine the effect of inhibiting de novo lipogenesis on lipid accumulation in chondrocytes. When compared to the mice receiving LFD, the HFD group displayed more chondrocytes with visible intracellular lipid droplets. Significantly higher amounts of total FAs were also detected in the HFD group. Five out of six significantly upregulated FAs were ω-6 FAs, while the two significantly downregulated FAs were ω-3 FAs. Consequently, the HFD group displayed a significantly higher ω-6/ω-3 FA ratio. Ether linked phosphatidylcholine was also found to be higher in the HFD group. Fatty acid desaturase (Fad1-3), fatty acid-binding protein 4 (Fabp4), and fatty acid synthase (Fasn) transcripts were not found to be different between the treatment groups and fatty acid elongase (Elovl1-7) transcripts were undetectable in cartilage. Ceramide synthase 2 (Cers-2), the only transcript found to be changed in these studies, was significantly upregulated in the HFD group. In vitro, chondrocytes upregulated de novo lipogenesis when cultured under high-glucose, high-insulin conditions, and this observation was associated with the activation of ACC, which was attenuated by the addition of ND-630. This study provides the first evidence that lipid deposition is increased in cartilage with obesity and that this is associated with the upregulation of ACC-mediated de novo lipogenesis. This was supported by our observation that ACC inhibition ameliorated lipid accumulation in chondrocytes, thereby suggesting that ACC could potentially be targeted to treat obesity-associated OA.

Identification of Symptom Phenotypes of Hand Osteoarthritis Using Hierarchical Clustering: Results From the DIGICOD Cohort

OBJECTIVE

We aimed to delineate phenotypes in hand osteoarthritis (HOA) based on cardinal symptoms (pain, functional limitation, stiffness, and aesthetic discomfort).

METHODS

With data from the Digital Cohort Design (DIGICOD), we performed a hierarchical agglomerative clustering analysis based on Australian/Canadian Osteoarthritis Hand Index (AUSCAN) subscores for pain, physical function, stiffness, and visual analog scale for aesthetic discomfort. Kruskal-Wallis and post hoc analyses were used to assess differences between clusters.

RESULTS

Among 389 patients, we identified 5 clusters: cluster 1 (n = 88) and cluster 2 (n = 91) featured low and mild symptoms; cluster 3 (n = 80) featured isolated aesthetic discomfort; cluster 4 (n = 42) featured a high level of pain, stiffness, and functional limitation; and cluster 5 (n = 88) had the same features as cluster 4 but with high aesthetic discomfort. For clusters 4 and 5, AUSCAN pain score was >41 of 100, representing only one-third of our patients. Aesthetic discomfort (clusters 3 and 5) was significantly associated with erosive HOA and a higher number of nodes. The highly symptomatic cluster 5 was associated but not significantly with metabolic syndrome, and body mass index and C-reactive protein level did not differ among clusters. Symptom intensity was significantly associated with joint destruction as well as with physical and psychological burden. Patients' main expectations differed among clusters, and function improvement was the most frequent expectation overall.

CONCLUSION

The identification of distinct clinical clusters based on HOA cardinal symptoms suggests previously undescribed subtypes of this condition, warranting further study of biological characteristics of such clusters, and opening a path toward phenotype-based personalized medicine in HOA.

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.

Musculoskeletal Conditions in Persons Living with HIV/AIDS: A Scoping Review

OBJECTIVE

Globally 37.9 million people are living with HIV/AIDS, and with mortality rates declining, there is an increasing focus on comorbidities including musculoskeletal (MSK) disorders. Therefore, the aim of this scoping review was to generate and summarize an overview of the existing scientific literature dealing with MSK complaints in people living with HIV/AIDS (PLWHAs).

METHODS

This scoping review followed the five-stage methodological framework proposed by Arksey and O'Malley. We searched PubMed, EMBASE, CINAHL, and the Cochrane Library from inception to June 1, 2020. Two reviewers independently reviewed the articles for eligibility. A data extraction form was used to chart information such as author, year of publication, data source, sample size, country of origin, ethnicity, age, gender, antiretroviral therapy, MSK condition prevalence, and anatomical location.

RESULTS

The search identified 10 522 articles. Of these, 27 studies were included after full-text screening for data extraction. Studies were conducted in thirteen different countries with diverse data sources such as outpatient clinic files, hospital records, primary care clinic files, and AIDS Service Organization files. PLWHAs have a variety of MSK conditions. Most studies reported spinal pain such as lower back or neck pain, but pain in the extremities and osteoarthritis (OA) were also represented. However, the frequencies of pain at various anatomical sites were highly variable.

CONCLUSION

There is a lack of knowledge regarding MSK conditions in PLWHAs. Future studies designed to specifically study MSK complaints and disabilities are needed to gain a better picture of the impact of these conditions in PLWHAs and to inform prevention and treatment strategies globally in this often-underserved population.

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.

Sirt5 Deficiency Causes Posttranslational Protein Malonylation and Dysregulated Cellular Metabolism in Chondrocytes Under Obesity Conditions

OBJECTIVE

Obesity accelerates the development of osteoarthritis (OA) during aging and is associated with altered chondrocyte cellular metabolism. Protein lysine malonylation (MaK) is a posttranslational modification (PTM) that has been shown to play an important role during aging and obesity. The objective of this study was to investigate the role of sirtuin 5 (Sirt5) in regulating MaK and cellular metabolism in chondrocytes under obesity-related conditions.

METHODS

MaK and SIRT5 were immunostained in knee articular cartilage of obese db/db mice and different aged C57BL6 mice with or without destabilization of the medial meniscus surgery to induce OA. Primary chondrocytes were isolated from 7-day-old WT and Sirt5^-/- mice and treated with varying concentrations of glucose and insulin to mimic obesity. Sirt5-dependent effects on MaK and metabolism were evaluated by western blot, Seahorse Respirometry, and gas/chromatography-mass/spectrometry (GC-MS) metabolic profiling.

RESULTS

MaK was significantly increased in cartilage of db/db mice and in chondrocytes treated with high concentrations of glucose and insulin (Glu^hiIns^hi). Sirt5 was increased in an age-dependent manner following joint injury, and Sirt5 deficient primary chondrocytes had increased MaK, decreased glycolysis rate, and reduced basal mitochondrial respiration. GC-MS identified 41 metabolites. Sirt5 deficiency altered 13 distinct metabolites under basal conditions and 18 metabolites under Glu^hiIns^hi treatment. Pathway analysis identified a wide range of Sirt5-dependent altered metabolic pathways that include amino acid metabolism, TCA cycle, and glycolysis.

CONCLUSION

This study provides the first evidence that Sirt5 broadly regulates chondrocyte metabolism. We observed changes in SIRT5 and MaK levels in cartilage with obesity and joint injury, suggesting that the Sirt5-MaK pathway may contribute to altered chondrocyte metabolism that occurs during OA development.

Degenerative joint changes following intra-articular fracture are more severe in mice with T cell deficiency

The inflammatory response to joint injury, specifically intra-articular fracture, has been implicated in posttraumatic arthritis development. However, the role of T cells in regulating the development of posttraumatic arthritis is unclear. We hypothesized that the absence of T cells would lead to less severe posttraumatic arthritis following intra-articular fracture. T cell-deficient, athymic nude, and wild-type C57BL/6NJ mice were assessed at 8 weeks following closed articular fracture. Joints were assessed using histologic scores of arthritis, synovitis, and bone morphology via micro computed tomography. Cells were profiled in whole blood via flow cytometry, and plasma and synovial fluid derived cytokines were quantified by multiplex analysis. Compared to C57BL/6NJ mice, nude mice had significantly greater histologic evidence of arthritis and synovitis. Whole blood immune cell profiling revealed a lower percentage of dendritic cells but increased natural killer (NK) cells in nude mice. Concurrently, nude mice had significantly higher levels of NK cells in synovial tissue. Concentrations of plasma interleukin 1β (IL-1β) and tumor necrosis factor α, and synovial fluid IL-12, IL-17, and IL-6 in both knees were greater in nude mice. Outcomes of this study suggest that T cells may play a protective regulatory role against the development of posttraumatic arthritis. Clinical significance: Lack of functional T cells exacerbated the development of posttraumatic arthritis following intra-articular fracture suggesting that critical regulators of the immune responses, contained within the T cell population, are required for protection. Future research identifying the specific T cell subsets responsible for modulating disease immunopathogenesis will lead to new therapeutic targets to mitigate posttraumatic arthritis.

Fatty acids and osteoarthritis: the MOST study

OBJECTIVE

Inflammation worsens joint destruction in osteoarthritis (OA) and aggravates pain. Saturated and n-6 fatty acids (FAs) increase, whereas n-3 FAs reduce inflammation. We examined whether FA levels affected the development of OA.

DESIGN

We studied participants from the Multicenter Osteoarthritis study (MOST) at risk of developing knee OA. After baseline, repeated knee x-rays and MRIs were obtained and knee symptoms queried through 60 month follow-up. Using baseline fasting samples, serum FAs were analyzed with standard assays. After excluding participants with baseline OA, we defined two sets of cases: those developing radiographic OA and those developing symptomatic OA (knee pain and radiographic OA). Controls did not develop these outcomes. Additionally, we examined worsening of MRI cartilage loss and synovitis and of knee pain using WOMAC and evaluated the number of hand joints affected by nodules. In regression models, we tested the association of each OA outcome with levels of saturated, n-3 and n-6 FAs adjusting for age, sex, BMI, education, race, baseline pain and depressive symptoms.

RESULTS

We studied 260 cases with incident symptomatic and 259 with incident radiographic OA. Mean age was 61 years (61% women). We found no signficant nor suggestive associations of FA levels with incident OA (e.g., for incident symptomatic OA, OR per s.d. increase in n-3 FA 1.00 (0.85, 1.18) nor with any OA outcome in knee or hand.

CONCLUSION

Despite previously described effects on systemic inflammation, blood levels of FAs were not associated with risk of later knee OA or other OA outcomes.

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.

The DIGICOD cohort: A hospital-based observational prospective cohort of patients with hand osteoarthritis - methodology and baseline characteristics of the population

OBJECTIVE

Despite its prevalence, there are few worldwide hand osteoarthritis (HOA) cohorts. The main objective of DIGItal COhort Design (DIGICOD) cohort is to investigate prognostic clinical, biological, genetic and imaging factors of clinical worsening after 6years follow-up.

METHODS

DIGICOD is a hospital-based prospective cohort including patients>35years-old with symptomatic HOA fulfilling: (i) ACR criteria for HOA with≥2 symptomatic joints among proximal/distal interphalangeal joints or 1st interphalangeal joint with Kellgren-Lawrence (KL)≥2; or (ii) symptomatic thumb base OA with KL≥2. Main exclusion criteria were inflammatory arthritis and crystal arthropathies. Annual clinical evaluations were scheduled with imaging (X-rays of the hands and of other OA symptomatic joints) and biological sampling every 3years. Hand radiographs are scored using KL and anatomical Verbruggen-Veys scores. Follow-up visits are ongoing. Cohort methodology and baseline characteristics are presented.

RESULTS

Between April 2013 and June 2017, from the 436 HOA included patients, 426 have been analysed of whom 357 (84%) are women. Mean age±standard deviation was 66.7±7.3years and mean disease duration was 12.6±9.6years. Metabolic syndrome affected 151 (36.5%) patients. Mean Visual Analog Scale (VAS) hand pain (0-100mm) was 44.4±26.7mm at activity. Mean FIHOA (0-100) was 19.9±18.6. Elevated serum CRP level (≥5mg/L) involved 10% patients. Mean KL score (0-128) was 46.7±18 and the mean number of joint with KL≥2 was 15.1±6.3. Erosive HOA (defined as≥1 Erosive or Remodeling phase joint according to Verbruggen-Veys score) involved 195/426 (45.8%) patients and the median number (interquartile range) of erosive joints in erosive patients was 3.0 (1.0-5.0).

CONCLUSION

DIGICOD is a unique prospective HOA cohort with a long-term 6years standardized assessment and has included severe radiologically HOA patients with a high prevalence of erosive disease.

Pain in women with knee and/or hip osteoarthritis is related to systemic inflammation and to adipose tissue dysfunction: Cross-sectional results of the KHOALA cohort

BACKGROUND

Considering the role of metabolic diseases in osteoarthritis (OA), we investigated whether biomarkers of adipose tissue dysfunction could be associated with OA-related pain.

DESIGN

We cross-sectionally analyzed patients with knee and/or hip OA at inclusion in the KHOALA cohort. We used visual analogic scale (VAS) for pain, the Western Ontario and McMaster Universities Arthritis Index (WOMAC) and Osteoarthritis Knee and Hip Quality of Life (OAKHQOL) pain subscores. At inclusion, we measured ultra-sensitive CRP (usCRP), leptin and adiponectin for calculation of leptin:adiponectin ratio (LAR), a marker of adipose tissue dysfunction associated with central adiposity, high-molecular-weight adiponectin, visfatin and apolipoproteins. Univariate and multivariable analyses using stepwise linear regression models were performed to search for correlation between pain assessments and these biomarkers, with systematic adjustment on age.

RESULTS

In 596 women with hip and/or knee OA, multivariable analyses indicated that higher pain intensity was associated with higher LAR (VAS pain: β=0.49; p = 0.0001, OAKHQOL pain: β=-0.46; p = 0.0002, WOMAC pain: β=0.30; p = 0.001) in the whole group as well as in hip or knee OA patients considered separately. Pain intensity correlated also with usCRP level (VAS pain: β= 0.27; p = 0.02, OAKHQOL pain: β =-0.30; p = 0.01) and Kellgren-Lawrence score. In 267 men, no correlation between biomarkers and pain was found.

CONCLUSION

Serum LAR and usCRP level are associated with pain level, independently of radiographic structural severity in women with hip and/or knee OA, emphasizing the role of adipose tissue dysfunction and of meta-inflammation in pain experience in the female population.

Osteoarthritis and type 2 diabetes: From pathogenetic factors to therapeutic intervention

Over the last decades, osteoarthritis (OA) and type 2 diabetes (T2D) prevalence increased due to the global ageing population and the pandemic obesity. They currently affect a substantial part of the Western world population and are characterized by enhancing the risk of disability and reduction of quality of life. OA is a multifactorial condition whose development derives from the interaction between individual and environmental factors: The best known primarily include age, female gender, genetic determinants, articular biomechanics, and obesity (OB). Given the high prevalence of OA and T2D and their association with OB and inflammation, several studies have been conducted to investigate the causative role of biological characteristics proper to T2D on the development of OA. This review aims to analyse the relationship between of OA and T2D, in order to explain the pathophysiological drivers of the degenerative process and to delineate possible targets to which appropriate treatments may be addressed in the near future.

Metabolic and inflammatory links to rotator cuff tear in hand osteoarthritis: A cross sectional study

Objectives

To estimate the prevalence and associated factors of rotator cuff tear (RCT) in patients with hand osteoarthritis (HOA).

Methods

Between June 2013 and December 2015, we recruited 1150 participants in rural area of South Korea. Of the 1150 participants, 307 participants with HOA were analyzed. Plain radiography of both hands, magnetic resonance imaging of both shoulders, and serum levels of high-sensitive C-reactive protein (hsCRP) and high-density lipoprotein (HDL) were obtained for all patients. HOA and RCT were diagnosed by clinical and radiologic findings.

Results

The prevalence of RCT in patients with HOA (192/307, 62.5%) was higher than that in those without HOA (410/827, 49.5%, p<0.001). Among the 307 patients with HOA, the patients with RCT were older, and had higher hsCRP and lower HDL levels than the patients without RCT. Multiple logistic regression analysis confirmed significant associations of age (odds ratio [OR], 1.06; 95% confidence interval [CI], 1.02–1.11), serum hsCRP levels ≥0.6mg/L (OR, 1.68; CI, 1.00–2.80), and low HDL levels (male, <50 mg/dL; female, <40 mg/dL) (OR, 1.93; CI, 1.05–3.56) with RCT in patients with HOA. For patients below 60 years old, the prevalence of RCT was 2.8-fold higher in the low HDL group than normal HDL group (p = 0.048). Finally, the prevalence of RCT was 2.6-fold higher in patients with HOA with both elevated hsCRP and low HDL levels compared with those with neither (p<0.05).

Conclusions

Our findings suggest inflammation and metabolic factors were associated with the prevalence of RCT in HOA patients.

Metabolic complications affecting adipose tissue, lipid and glucose metabolism associated with HIV antiretroviral treatment

Introduction: Efficient antiretroviral-treatment (ART) generally allows control of HIV infection. However, persons-living-with-HIV (PLWH), when aging, present a high prevalence of metabolic diseases. Area covered: Altered adiposity, dyslipidemias, insulin resistance, diabetes, and their consequences are prevalent in PLWH and could be partly related to ART. Expert opinion: At first, personal and lifestyle factors are involved in the onset of these complications. The persistence of HIV in tissue reservoirs could synergize with some ART and enhance metabolic disorders. Altered fat repartition, diagnosed as lipodystrophy, has been related to first-generation nucleoside-reverse-transcriptase-inhibitors (NRTIs) (stavudine zidovudine) and some protease inhibitors (PIs). Recently, use of some integrase-inhibitors (INSTI) resulted in weight/fat gain, which represents a worrisome unresolved situation. Lipid parameters were affected by some first-generation NRTIs, non-NRTIs (efavirenz) but also PIs boosted by ritonavir, with increased total and LDL-cholesterol and triglycerides. Insulin resistance is common associated with abdominal obesity. Diabetes incidence, high with first-generation-ART (zidovudine, stavudine, didanosine, indinavir) has declined with contemporary ART close to that of the general population. Metabolic syndrome, a dysmetabolic situation with central obesity and insulin resistance, and liver steatosis are common in PLWH and could indirectly result from ART-associated fat gain and insulin resistance. All these dysmetabolic situations increase the atherogenic cardiovascular risk.

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.

Is treated HIV infection associated with knee cartilage degeneration and structural changes? A longitudinal study using data from the osteoarthritis initiative

Background

Metabolic disorders presenting in HIV-infected patients on antiretroviral therapy (ART) may increase the risk of osteoarthritis. However, structural changes of the knee in HIV infected subjects are understudied. The aim of this study is to investigate knee cartilage degeneration and knee structural changes over 8 years in subjects with and without HIV infection determined based on the use of ART.

Methods

We studied 10 participants from the Osteoarthritis Initiative who received ART at baseline and 20 controls without ART, frequency matched for age, sex, race, baseline body mass index (BMI) and Kellgren & Lawrence grade. Knee abnormalities were assessed using the whole-organ magnetic resonance imaging score (WORMS) and cartilage T2 including laminar and texture analyses were analyzed using a multislice-multiecho spin-echo sequence. Signal abnormalities of the infrapatellar fat pad (IPFP) and suprapatellar fat pad (SPFP) were assessed separately using a semi-quantitative scoring system. Linear regression models were used in the cross-sectional analysis to compare the differences between ART/HIV subjects and controls in T2 (regular and laminar T2 values, texture parameters) and morphologic parameters (subscores of WORMS, scores for signal alterations of IPFP and SPFP). Mixed effects models were used in the longitudinal analysis to compare the rate of change in T2 and morphological parameters between groups over 8 years.

Results

At baseline, individuals on ART had significantly greater size of IPFP signal abnormalities (P = 0.008), higher signal intensities of SPFP (P = 0.015), higher effusion scores (P = 0.009), and lower subchondral cysts sum scores (P = 0.003) compared to the controls. No significant differences were found between the groups in T2-based cartilage parameters and WORMS scores for cartilage, meniscus, bone marrow edema patterns and ligaments (P > 0.05). Longitudinally, the HIV cohort had significantly higher global knee T2 entropy values (P = 0.047), more severe effusion (P = 0.001) but less severe subchondral cysts (P = 0.002) on average over 8 years.

Conclusions

Knees of individuals with HIV on ART had a more heterogeneous cartilage matrix, more severe synovitis and abnormalities of the IPFP and SPFP, which may increase the risk of incident knee osteoarthritis.

Electronic supplementary material

The online version of this article (10.1186/s12891-019-2573-5) contains supplementary material, which is available to authorized users.

The Phenotypic Approach to Osteoarthritis: A Look at Metabolic Syndrome-Associated Osteoarthritis

Metabolic syndrome-associated osteoarthritis (Met-OA) is a clinical phenotype defined by the role of obesity and metabolic syndrome as risk factors and by chronic low-grade inflammation. Obesity is an established risk factor for osteoarthritis not only at the knee, but also at the hands. Metabolic syndrome is also a risk factor for osteoarthritis, and a cumulative effect of the various syndrome components combines with an independent effect of each individual component (diabetes, dyslipidemia, and/or hypertension). The higher incidence of osteoarthritis in patients with obesity is related to several factors. One is the larger fat mass, which imposes heavier loads on the joints. Another is endocrine production by the adipose tissue of proinflammatory mediators (cytokines, adipokines, fatty acids, and reactive oxygen species) that adversely affect joint tissues. Obesity-related dysbiosis and sarcopenia were more recently implicated in the association between obesity and osteoarthritis. Finally, patients who have osteoarthritis, with or without metabolic syndrome, are at increased risk for cardiovascular mortality due not only to a sedentary lifestyle, but also to shared risk factors. Among these is the low-grade inflammation seen in patients with metabolic disorders. Thus, primary prevention and appropriate management of obesity and metabolic syndrome may delay the development and slow the progression of osteoarthritis.

Prediction of midlife hand osteoarthritis in young men

OBJECTIVES

Improved prediction modeling in osteoarthritis (OA) may encourage risk reduction through calculation of individual and population lifetime risks. There are currently no prediction models for hand OA. Thus, we aimed to 1) develop a prediction model for hand OA in men and 2) to contrast its discriminative performance to a prediction model for lung cancer and chronic obstructive pulmonary disease (COPD).

METHODS

We included 40,118 men aged 18 years undergoing mandatory conscription in Sweden 1969-70. Incident hand OA and lung cancer/COPD were obtained from diagnostic codes in the Swedish National Patient Register 1987-2010, i.e., until subjects were 59 years of age. We studied the strongest candidate predictors from five domains; socioeconomic, local biomechanical, systemic, lifestyle-related and general health factors, using logistic regression with backward elimination of candidate predictors with P > 0.2 to determine final models. To avoid overfitting we used bootstrapping.

RESULTS

The strongest predictors for hand OA were body mass index (BMI), elbow flexor strength, systolic blood pressure, lower education and sleep problems. We observed excellent agreement between observed and predicted values, yet the discrimination was moderate (Area Under the Curve [AUC] = 0.62, 95% CI = 0.58-0.64). The discrimination in the prediction model for lung cancer/COPD was good (AUC = 0.74, 95% CI = 0.72-0.76).

CONCLUSION

This prediction model for hand OA was capable of discriminating between persons with and without hand OA to a similar extent that has been previously reported for knee OA. Still, prediction of OA is more challenging than for chronic pulmonary disease.

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.

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

OBJECTIVE

To explore whether metabolic syndrome and its components are associated with hand osteoarthritis (OA) using longitudinal data from the Framingham Study.

METHODS

Our cross-sectional analyses included 1,089 persons (ages 50-75 years), of whom 785 had longitudinal radiographs obtained 7 years apart. Of these, 586 with no hand OA at baseline were included in analyses of hand OA incidence. We explored associations between metabolic syndrome and its components (central obesity, hypertension, diabetes mellitus, triglyceridemia, and low high-density lipoprotein) and radiographic hand OA (defined as ≥2 interphalangeal joints with a Kellgren/Lawrence [K/L] grade of ≥2) using logistic regression analyses with adjustment for age, sex, and body mass index. In longitudinal analyses, metabolic syndrome was used as a predictor for change in K/L sum score and incident hand OA.

RESULTS

Metabolic syndrome was not associated with the presence of hand OA (odds ratio [OR] 1.11 [95% confidence interval (95% CI) 0.78-1.59]), change in K/L sum score (OR 0.83 [95% CI 0.59-1.17]), or incidence of hand OA (OR 0.91 [95% CI 0.58-1.44]). Hypertension was borderline significantly associated with the presence of hand OA (OR 1.25 [95% CI 0.90-1.74]), and a significant association was found between hypertension and change in K/L sum score (OR 1.47 [95% CI 1.08-1.99]). Consistent dose-response relationships were not demonstrated (data not shown). Furthermore, hypertension was not significantly associated with hand OA incidence (OR 1.23 [95% CI 0.82-1.83]). No significant associations were found between metabolic syndrome and erosive hand OA.

CONCLUSION

We found no association between metabolic syndrome and hand OA. The role of hypertension in hand OA pathogenesis warrants further investigation.

Metabolic syndrome-associated osteoarthritis

PURPOSE OF REVIEW

Interest in the metabolic syndrome-associated osteoarthritis phenotype is increasing. Here, we summarize recently published significant findings.

RECENT FINDINGS

Meta-analyses confirmed an association between type 2 diabetes and osteoarthritis and between cardiovascular diseases and osteoarthritis. Recent advances in the study of metabolic syndrome-associated osteoarthritis have focused on a better understanding of the role of metabolic diseases in inducing or aggravating joint damage. In-vivo models of obesity, diabetes, or dyslipidemia have helped to better decipher this association. They give emerging evidence that, beyond the role of common pathogenic mechanisms for metabolic diseases and osteoarthritis (i.e., low-grade inflammation and oxidative stress), metabolic diseases have a direct systemic effect on joints. In addition to the impact of weight, obesity-associated inflammation is associated with osteoarthritis severity and may modulate osteoarthritis progression in mouse models. As well, osteoarthritis synovium from type 2 diabetic patients shows insulin-resistant features, which may participate in joint catabolism. Finally, exciting data are emerging on the association of gut microbiota and circadian rhythm and metabolic syndrome-associated osteoarthritis.

SUMMARY

The systemic role of metabolic syndrome in osteoarthritis pathophysiology is now better understood, but new avenues of research are being pursued to better decipher the metabolic syndrome-associated osteoarthritis phenotype.

Osteoarthritis and type 2 diabetes mellitus: What are the links?

Osteoarthritis (OA) is the most frequent joint disorder and one of the leading cause of disability. During a long time, it was considered as the consequence of aging and mechanical stress on cartilage. Recent advances in the knowledge of OA have highlighted that it is a whole joint disease with early modifications of synovium and subchondral bone but also that it is associated with obesity and metabolic syndrome through systemic mechanisms. In the past year, type 2 diabetes has been described in two meta-analyzes as an independent risk factor for OA. In vivo models of diabetes corroborated epidemiological studies. Indeed, diabetic rodents display a spontaneous and a more severe experimental OA than their non-diabetic counterparts, which can be partially prevented by diabetes treatment (insulin, pioglitazone). The negative impact of diabetes on joints could be explain by the induction of oxidative stress and pro-inflammatory cytokines but also by advanced age products accumulation in joint tissues exposed to chronic high glucose concentration. Insulin resistance might also impair joint tissue because of a local insulin resistance of diabetic synovial membrane but also by the systemic low grade inflammation state related to obesity and insulin resistant state.