Serum levels of vitamin D, sunlight exposure, and knee cartilage loss in older adults: the Tasmanian older adult cohort study

Relationship between serum vitamin D levels and the prevalence of knee osteoarthritis: A retrospective study on 3424 subjects

BACKGROUND

The extent of the association between vitamin D deficiency and knee osteoarthritis remains inadequately understood.

OBJECTIVE

This study aimed to elucidate the relationship between vitamin D levels and knee osteoarthritis through a cross-sectional analysis.

METHODS

This retrospective study involved an analysis of knee radiographs and serum 25-hydroxyvitamin D3 (25-(OH) vitamin D3) levels in a cohort of 3424 individuals (2901 women and 523 men). Knee osteoarthritis severity was evaluated using the Kellgren-Lawrence radiological scoring system.

RESULTS

Of the participants, 49.2% (n= 1,683) were diagnosed with knee osteoarthritis. Among these patients, the levels of adjusted 25-(OH) vitamin D3 were significantly lower (p< 0.001). Regression analysis revealed a significant association between vitamin D deficiency and knee osteoarthritis, with an adjusted odds ratio (OR) of 1.7 (95% CI: 1.5-2.0; p< 0.001). Notably, a stronger association was observed between vitamin D deficiency and knee osteoarthritis in women under 65 compared to those aged 65 and above.

CONCLUSIONS

The findings of this study indicate a higher prevalence of vitamin D deficiency in patients with knee osteoarthritis. Maintaining adequate serum 25-(OH) vitamin D3 levels may prevent knee osteoarthritis, especially in women below 65.

Vitamin D and autophagy in knee osteoarthritis: A review

Knee osteoarthritis (KOA), the highly prevalent degenerative disease affecting the joint, perpetually devastates the health of the elderly. Of various mechanisms known to participate in KOA etiology, apoptosis of chondrocytes is widely regarded as the primary cause of cartilage degradation. It has been suggested that the induction of autophagy in chondrocytes could potentially prolong the progression of KOA by modulating intracellular metabolic processes, which may be helpful for ameliorating chondrocyte apoptosis and eventual cartilage degeneration. Autophagy, a physiological process characterized by intracellular self-degradation, has been reportedly implicated in various pathologic conditions including KOA. Interestingly, vitamin D has been shown to regulate autophagy in human chondrocytes through multiple pathways, specifically AMPK/mTOR signaling pathway. This observation underscores the potential of vitamin D as a novel approach for restoring the functionality and survivability of chondrocytes in KOA. Supporting vitamin D's clinical significance, previous studies have demonstrated its substantial involvement in the symptoms and irregular joint morphology observed in KOA patients, strengthening potential therapeutic efficacy of vitamin D in treatment of KOA. Herein, the purpose of this review was to determine the mechanisms underlying the multi-processes of vitamin D implicated in autophagy in several cells including chondrocytes, which would bring unique insights into KOA pathogenesis.

Relationship between 25-hydroxy vitamin D and knee osteoarthritis: a systematic review and meta-analysis of randomized controlled trials

Objective

In order to examine the relationship between 25-hydroxyl vitamin D and knee osteoarthritis (KOA), a meta-analysis of 8 randomized controlled trials (RCTs) publications was hereby performed.

Methods

For the purpose of finding pertinent research, the databases of PubMed, Embase and the Cochrane Library were searched. Factors including tibial cartilage volume, joint space width (JSW), synovial fluid volume, and Western Ontario and McMaster Universities Arthritis Index (WOMAC) were correspondingly evaluated, and the results were expressed using SMD and 95% confidence intervals (CI).

Results

The present meta-analysis evaluated the effects of vitamin D supplementation in patients with knee osteoarthritis, with 3,077 patients included. The results showed that vitamin D administration had a statistically significant impact on the amount of synovial fluid, Visual Analog Scale (VAS) and tibial cartilage. The pain and function scales of the WOMAC scale presented a statistically significant difference, and there was no discernible difference between the vitamin D and placebo groups in the stiffness scale. Additionally, bone marrow lesions and alterations in the diameter of the joint space were not influenced by the administration of vitamin D, and according to a subgroup study, a daily vitamin D supplement containing more than 2,000 IU significantly slowed the development of synovial tissue.

Conclusion

Vitamin D supplementation did benefit those suffering from knee discomfort and knee dysfunction.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022332033, identifier: CRD42022332033.

The association of vitamin D status with oxidative stress biomarkers and matrix metalloproteinases in patients with knee osteoarthritis

Objective

The association of vitamin D status with osteoarthritis (OA) has been demonstrated previously. The current study was performed to examine the association of vitamin D status with oxidative stress markers and matrix metalloproteinases (MMPs) in patients with knee OA.

Methods

This case-control study was conducted on 124 subjects with mild to moderate knee OA and 65 healthy controls. Demographic data was collected from all participants at baseline. Serum levels of vitamin D as well as markers of oxidative stress including malondialdehyde (MDA), total oxidant status (TOS), superoxide dismutase (SOD), oxidative stress index (OSI), paraoxonase-1 (PON-1), glutathione peroxidase (GPX), catalase (CAT), and total antioxidant capacity (TAC) were evaluated for each participant. Furthermore, serum concentrations of MMP-1, MMP-3, MMP-13, and cartilage oligomeric matrix protein (COMP) were measured.

Results

The results of the present study indicated that individuals with vitamin D insufficiency had higher levels of MDA, TOS, SOD, and OSI as well as lower levels of PON-1 and TAC. Based on the linear regression analysis, serum vitamin D levels were inversely correlated with MDA, TOS, SOD, OSI, MMP-1, and MMP-13 and positively associated with TAC levels (p < 0.0001). Patients with sufficient vitamin D levels had lower MMP-1 and MMP-13 levels compared to patients with vitamin D insufficiency (p < 0.001 and p < 0.001, respectively).

Conclusion

Findings from this study showed a strong association between vitamin D deficiency and increased oxidative stress and MMPs activity in patients with knee OA.

The relationship of biochemical factors related to calcium metabolism with temporomandibular disorders

OBJECTIVE

The aim of this study is to investigate the relationship between calcium metabolism-related biochemical factors (alkaline phosphatase, vitamin D, parathyroid hormone (PTH), calcium, phosphorus and magnesium), and temporomandibular joint (TMJ) disk displacement with reduction (DDWR).

MATERIALS AND METHODS

This prospective observational study included patients with temporomandibular disorders (TMDs) (n = 50) and healthy controls (n = 50) of similar age and sex. The diagnosis of TMJ DDWR was made using the diagnostic criteria for temporomandibular joint disorders (DC/TMD). Both groups were compared in terms of serum alkaline phosphatase, 25 (OH) vitamin D, PTH, calcium, magnesium, and phosphorus levels. P<0.005 was accepted as a significant difference.

RESULTS

There was no significant difference between the groups in terms of age, gender, and body mass index (BMI). Calcium levels of patients with TMD were statistically significantly lower than control patients (p<0.05). While there was no significant difference between the two groups in terms of mean VIT D, the number of people with severe Vit D deficiency (<10 ng) in the TMD group was significantly higher than in the control group (p<0.05). There was no statistically significant difference between the groups in terms of serum alkaline phosphatase, magnesium, phosphorus and PTH levels.

CONCLUSION

The differences in serum calcium and vitamin D levels seen in the study indicate that biochemical factors related to calcium metabolism may be associated with TMJ DDWR. These results suggest that calcium and vitamin D deficiency should be evaluated and corrected in patients with TMD.

The Role of Vitamin D in the Development and Progression of Osteoarthritis

"Low levels of vitamin D in patients with osteoarthritis (ΟΑ) rather adversely affect the structure and function of articular cartilage. Low levels of vitamin D are also associated with joint pain, limited physical activity, quality of life, as well as decreased muscle strength, primarily in the lower extremities with adverse OA progression. A high percentage of low vitamin D levels was found in patients with OA and joint arthroplasty as well as a less satisfactory postoperative follow-up in patients with low vitamin D levels. The administration of vitamin D supplementation in patients with knee osteoarthritis has been associated with improved articular cartilage architecture, and reduced joint pain, combined with improved functionality and quality of life in patients with OA. "

Latest insights in disease-modifying osteoarthritis drugs development

Osteoarthritis (OA) is a prevalent and severely debilitating disease with an unmet medical need. In order to alleviate OA symptoms or prevent structural progression of OA, new drugs, particularly disease-modifying osteoarthritis drugs (DMOADs), are required. Several drugs have been reported to attenuate cartilage loss or reduce subchondral bone lesions in OA and thus potentially be DMOADs. Most biologics (including interleukin-1 (IL-1) and tumor necrosis factor (TNF) inhibitors), sprifermin, and bisphosphonates failed to yield satisfactory results when treating OA. OA clinical heterogeneity is one of the primary reasons for the failure of these clinical trials, which can require different therapeutic approaches based on different phenotypes. This review describes the latest insights into the development of DMOADs. We summarize in this review the efficacy and safety profiles of various DMOADs targeting cartilage, synovitis, and subchondral bone endotypes in phase 2 and 3 clinical trials. To conclude, we summarize the reasons for clinical trial failures in OA and suggest possible solutions.

Effectiveness of vitamin D supplementation on knee osteoarthritis - A target trial emulation study using data from the Osteoarthritis Initiative cohort

OBJECTIVE

To assess the real-world effectiveness of vitamin D supplementation in patients with knee osteoarthritis (KOA) by replicating a randomized controlled trial (RCT) design in an observational study.

METHOD

This study emulated a target trial using data from the Osteoarthritis Initiative (OAI). Eligible participants were ≥45 years, had symptomatic KOA and did not take vitamin D supplements in the past 30 days. A participant can enter the trial more than once. Participants were included in vitamin D group if they took ≥1,000 IU/day for ≥4 days/week in the past 30 days at the first follow-up visit after baseline. The control group did not use vitamin D in the past 30 days. Optimal propensity score matching at 1:1 ratio was performed. The primary outcome was change in knee pain 2 years after baseline measured by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Secondary outcomes included WOMAC physical function and quantitative joint space width (JSW). Standardized mean difference (SMD) was used to compare the findings with previous RCTs.

RESULTS

A total of 236 person-trials in the vitamin D group were pair-matched with a control. Compared to the control group, vitamin D supplementation did not reach significant changes in WOMAC pain (SMD = -0.04, 95%CI [-0.21, 0.13]), physical function and radiographic JSW over 2 years. The SMDs were consistent with the effect sizes reported in previous RCTs.

CONCLUSION

Target trial emulation in the OAI cohort demonstrated findings close to published RCTs. This supports the future use of target trial emulation in evaluating other systemic therapies for KOA.

Associations of Dietary Macroelements with Knee Joint Structures, Symptoms, Quality of Life, and Comorbid Conditions in People with Symptomatic Knee Osteoarthritis

Background: Osteoarthritis (OA), the most common joint disease in the elderly, has no cure. Macroelements are vital in human health and their relationships with OA are not clear. Clarifying the relationships between macroelements and OA may assist knee OA management. Methods: This study was a post-hoc analysis using data from a two-year randomized controlled trial among 392 participants with knee OA. Dietary macroelements, including calcium, magnesium, potassium, and phosphorus were computed-based on a semi-quantitative food frequency questionnaire at baseline. Knee joint structures (including cartilage volume, cartilage defect, bone marrow lesions, and effusion-synovitis volume), OA symptoms, quality of life, and OA comorbid conditions (including lower limb muscle strength and depressive symptoms) were assessed at baseline and month 24. Western Ontario and McMaster Universities (WOMAC) Index and depressive symptoms were assessed at baseline and months 3, 6, 12, and 24. Quality of life and lower limb muscle strength were assessed at baseline and months 6, 12, and 24. All analyses were conducted using mixed-effects models. Results: Higher dietary magnesium and potassium were associated with fewer OA symptoms, higher quality of life, greater lower limb muscle strength, and fewer depressive symptoms, but not with knee joint structures. Higher dietary calcium and phosphorus was not associated with any of the OA-related outcomes, except that dietary phosphorus was associated with greater lower limb muscle strength. Conclusions: In the longitudinal analyses, higher dietary magnesium and potassium intake are associated with fewer OA symptoms, higher quality of life, and milder comorbid conditions in patients with knee OA, suggesting dietary magnesium and potassium may have beneficial effects on OA and could be used for knee OA management.

Older Korean men with inadequate vitamin D status have lower odds of radiologic osteoarthritis

Most studies on osteoarthritis (OA) and vitamin D status were performed in Whites with relatively adequate vitamin D status. Associations may differ by baseline 25-hydroxyvitamin D (25(OH)D) and race. We assessed the odds of OA and joint pain according to vitamin D status in Korean adults ≥ 50 years of age in the nationally representative Korea National Health and Nutrition Examination Survey (n = 8575). Agreement between radiologic OA (ROA) and self-reported OA were also assessed. Multivariate logistic regression was performed and participants were stratified by sex. Adults with serum 25(OH)D < 12 ng/mL and 12 to < 20 ng/mL had 26% and 18% lower odds of knee ROA, respectively, compared to those with 25(OH)D ≥ 20 ng/mL. Similar results were observed in men, but not women. No associations were found between 25(OH)D and knee ROA severity, lumbar spine ROA, symptomatic OA, or knee pain. Sensitivity of self-reported OA was low (27%), indicating a weak possibility of reverse causation. Prospective studies are required to identify the possible causality of vitamin D on OA in Korean men.

Effect of alendronate sodium plus vitamin D3 tablets on knee joint structure and osteoarthritis pain: a multi-center, randomized, double-blind, placebo-controlled study protocol

Background

Osteoarthritis (OA) is a major cause of pain and disability worldwide. Despite the relatively high burden of the disease, the currently available non-surgical treatment options are directed towards symptomatic relief. Therefore, we propose the use of alendronate as a disease modifying agent to help slow and prevent OA. In addition, this study will utilize Whole-Organ Magnetic Resonance Imaging Score (WORMS) to evaluate the structural integrity of cartilage in the study population. High-quality evidence, limited to a few well-conducted randomized trials, highlights contradictory results on the effect of bisphosphonates on knee function and progression of OA. Therefore, a placebo-controlled, randomized trial is needed to evaluate the combined effect of alendronate and vit D on the structure of cartilage utilizing the WORMS score and its ability to treat knee pain in OA patients.

Methods

This multicenter, randomized, double-blinded, placebo-controlled study will evaluate the efficacy and safety of alendronate in early OA. Patients will undergo a 1:1 double-blinded randomization to receive a one-year course of either alendronate sodium vitamin D₃ or placebo. The primary outcome is to compare WORMS score of knee joint at 6 and 12 months between both groups. Secondary endpoints will include WORMS score at 24 months, knee pain, radiographic progression of OA, severity of OA, quality of life, and serum inflammatory biomarkers at different assessment timepoints. To detect a 2.2% difference in cartilage loss between both groups with power of 80%, a sample size of 60 (30 per group) is proposed.

Discussion

This trial will give helpful and high-quality evidence regarding the potential therapeutic role of alendronate sodium vitamin D3, as compared to placebo, in the management of patients with knee OA regarding its role on cartilage loss, radiographic progression of OA, severity of OA, knee pain, quality of life, and inflammatory biomarkers. If proven effective, this intervention would be a great option for providing beneficial outcomes with a reduced cost in this patient population.

Trial registration

This trial was registered on clinicaltrials.gov (registration number: NCT04739592).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05521-4.

Nutraceutical Approach to Chronic Osteoarthritis: From Molecular Research to Clinical Evidence

Osteoarthritis (OA) is a degenerative inflammatory condition of the joint cartilage that currently affects approximately 58 million adults in the world. It is characterized by pain, stiffness, and a reduced range of motion with regard to the arthritic joints. These symptoms can cause in the long term a greater risk of overweight/obesity, diabetes mellitus, and falls and fractures. Although the current guidelines for the treatment of OA suggest, as the gold standard for this condition, pharmacological treatment characterized by non-steroidal anti-inflammatory drugs (NSAID), opioids, and cyclooxygenase (COX)-2-specific drugs, a great interest has been applied to nutraceutical supplements, which include a heterogeneous class of molecules with great potential to reduce inflammation, oxidative stress, pain, and joint stiffness and improve cartilage formation. The purpose of this review is to describe the potential application of nutraceuticals in OA, highlighting its molecular mechanisms of actions and data of efficacy and safety (when available).

Association of serum levels of inflammatory markers and adipokines with joint symptoms and structures in participants with knee osteoarthritis

OBJECTIVE

To investigate the longitudinal associations of serum inflammatory markers and adipokines with joint symptoms and structures in participants with knee osteoarthritis (OA).

METHODS

Two hundred participants (46.5% female, mean age 63.1 years, mean BMI 29.5 kg/m2) from Tasmania part of the VIDEO (Vitamin D Effect on OA) study were randomly selected in the current study. Serum levels of 19 biomarkers, scores of Western Ontario and McMaster Universities Index (WOMAC), and magnetic resonance imaging-assessed knee structures were evaluated at baseline and month 24. The patterns of biomarkers were derived from principal component analysis and their association with knee symptoms and structures were examined using adjusted generalized estimating equations.

RESULTS

Five components explained 78% of the total variance. Interleukin (IL)-1β, -2, -4, -6, -8, -17A, -17F, -21, -22 and -23 loaded the highest on the first component, which was associated with increased bone marrow lesions (BMLs) and WOMAC dysfunction score. IL-10, -12 and granulocyte-macrophage colony-stimulating factor loaded on the second component, which was associated with increased cartilage volume, and decreased effusion-synovitis and WOMAC scores. Leptin, adipsin and C-reactive protein loaded on the third component, which was positively associated with WOMAC scores. Resistin loaded on the fourth component, which was associated with increased BMLs and cartilage defects. Apelin-36 and adiponectin loaded on the fifth component, which was associated with increased BMLs.

CONCLUSION

Various inflammatory and metabolic components were associated differently with joint symptoms and structural changes in knee OA, suggesting a complex inflammatory and metabolic inter-relationship in the pathogenesis of knee OA.

New Trends in Pharmacological Treatments for Osteoarthritis

Osteoarthritis (OA) is the leading cause of function loss and disability among the elderly, with significant burden on the individual and society. It is a severe disease for its high disability rates, morbidity, costs, and increased mortality. Multifactorial etiologies contribute to the occurrence and development of OA. The heterogeneous condition poses a challenge for the development of effective treatment for OA; however, emerging treatments are promising to bring benefits for OA management in the future. This narrative review will discuss recent developments of agents for the treatment of OA, including potential disease-modifying osteoarthritis drugs (DMOADs) and novel therapeutics for pain relief. This review will focus more on drugs that have been in clinical trials, as well as attractive drugs with potential applications in preclinical research. In the past few years, it has been realized that a complex interaction of multifactorial mechanisms is involved in the pathophysiology of OA. The authors believe there is no miracle therapeutic strategy fitting for all patients. OA phenotyping would be helpful for therapy selection. A variety of potential therapeutics targeting inflammation mechanisms, cellular senescence, cartilage metabolism, subchondral bone remodeling, and the peripheral nociceptive pathways are expected to reshape the landscape of OA treatment over the next few years. Precise randomized controlled trials (RCTs) are expected to identify the safety and efficacy of novel therapies targeting specific mechanisms in OA patients with specific phenotypes.

Association of Gut Microbiome and Vitamin D Deficiency in Knee Osteoarthritis Patients: A Pilot Study

BACKGROUND

Few preclinical studies have shown that Knee osteoarthritis (KOA) is linked to gut microbiome dysbiosis and chronic inflammation. This pilot study was designed to look at the gut microbiome composition in KOA patients and normal individuals with or without vitamin D deficiency (VDD, serum vitamin D <30 ng/mL).

METHODS

This pilot study was conducted prospectively in 24 participants. The faecal samples of all the participants were taken for DNA extraction. The V3-V4 region of 16s rRNA was amplified, and the library was prepared and sequenced on the Illumina Miseq platform.

RESULTS

The mean (±SD) age was 45.5 (±10.2) years with no defined comorbidities. Of 447 total Operational Taxonomic Units (OTUs), a differential abundance of 16 nominally significant OTUs between the groups was observed. Linear discriminate analysis (LEfSe) revealed a significant difference in bacteria among the study groups. Pseudobutyrivibrio and Odoribacter were specific for VDD, while Parabacteroides, Butyricimonas and Gordonibacter were abundant in the KOA_VDD group, and Peptococcus, Intestimonas, Delftia and Oribacterium were abundant in the KOA group. About 80% of bacterial species were common among different groups and hence labelled as core bacterial species. However, the core microbiome of KOA and VDD groups were not seen in the KOA_VDD group, suggesting that these bacterial groups were affected by the interaction of the KOA and VDD factors.

CONCLUSION

Parabacteroides, Butyricimonas, Pseudobutyrivibrio, Odoribacter and Gordonibacter are the predominant bacteria in vitamin D deficient patients with or without KOA. Together these results indicate an association between the gut microbiome, vitamin D and knee osteoarthritis.

Does vitamin D improve symptomatic and structural outcomes in knee osteoarthritis? A systematic review and meta-analysis

OBJECTIVE

To provide evidence on the effects of vitamin D supplementation on knee osteoarthritis (KOA) and new targets for clinical prevention and treatment of KOA.

METHOD

The PubMed, Embase, Web of science, Wanfang, CNKI and SinoMed databases were retrieved to investigate the effects of vitamin D supplementation on patients with KOA. The search time was from databases establishment to 15 November 2020. RevMan5.3 software was used for meta-analysis. The results were expressed as standardized mean difference (SMD) with 95% confidence interval (CI) or weighted mean difference (WMD) with 95% confidence interval (CI).

RESULTS

A total of 1599 patients with osteoarthritis of the knee were included in the study, which involved six articles. The results of the meta-analysis showed that vitamin D supplementation is statistically significant for WOMAC score (SMD = - 0.67, 95% CI - 1.23 to - 0.12) in patients with KOA, including WOMAC pain score (SMD = - 0.32, 95% CI - 0.63 to - 0.02), function score (SMD = - 0.34, 95% CI - 0.60 to - 0.08) and stiffness score (SMD = - 0.13, 95% CI - 0.26 to - 0.01). In subgroup analysis, vitamin D supplementation less than 2000 IU was statistically significant for the reduction of stiffness score (SMD = - 0.22, 95% CI - 0.40 to - 0.04). Vitamin D supplements can reduce synovial fluid volume progression in patients with KOA (SMD = - 0.20, 95% CI - 0.39 to - 0.02). There was no statistical significance in improving tibia cartilage volume (SMD = 0.12, 95% CI - 0.05 to 0.29), joint space width (SMD = - 0.10, 95% CI - 0.26 to 0.05) and bone marrow lesions (SMD = 0.03, 95% CI - 0.26 to 0.31).

CONCLUSION

Vitamin D supplements can improve WOMAC pain and function in patients with KOA. But there is a lack of strong evidence that vitamin D supplementation can prevent structural progression in patients with KOA.

Associations between diet quality and knee joint structures, symptoms and systemic abnormalities in people with symptomatic knee osteoarthritis

BACKGROUND & AIMS

The evidence of benefiting from a high-quality diet for knee osteoarthritis (OA) joint structures, symptoms, and systemic abnormalities is limited. Clarifying the relationship between diet quality and knee OA could provide useful information for knee OA management. To investigate the associations between diet quality and knee joint structures, symptoms, lower limb muscle strength, depressive symptoms, and quality of life in people with knee OA.

METHODS

This study was a post-hoc, exploratory analysis using data from a randomized controlled trial in symptomatic knee OA participants with a follow-up time of 24 months. In brief, eligible participants of the original study were aged 50-79 years, had symptomatic knee OA, and had a pain of 20-80 mm on a 100-mm visual analog scale. After excluding the patients without information on diet quality, 392 participants were included in this post-hoc analysis. Diet quality was assessed at baseline using the Australian Recommended Food Score (ARFS) which includes subscores of vegetable, fruit, grain, dairy products, fat, and alcohol. Knee joint structures (including cartilage volume, cartilage defect, bone marrow lesions, and effusion-synovitis volume assessed by magnetic resonance imaging), OA symptoms, lower limb muscle strength, depressive symptoms, and quality of life were assessed at baseline and follow up. Mixed-effects models were used to assess the associations of diet quality with those outcomes.

RESULTS

Diet quality mainly reflect diet variety within the core food was not associated with knee structures and OA symptoms, but was associated with greater lower limb muscle strength (β = 0.66, P = 0.001), lower depressive symptom (β = -0.08, P = 0.001), and better quality of life (β = -0.06, P = 0.002). In further analyses of food group-based sub-scores, only the vegetable sub-score had the similar associations with lower limb muscle strength (β = 1.03, P = 0.004), depressive symptom (β = -0.17, P < 0.001), and quality of life (β = -0.14, P < 0.001).

CONCLUSIONS

Higher diet quality, mainly vegetable diet quality, is associated with greater lower limb muscle strength, less depressive symptoms, and higher quality of life in knee OA patients, suggesting higher diet quality may have protective effects on knee OA.

Review of Wearable and Portable Sensors for Monitoring Personal Solar UV Exposure

Sunlight is one of the main environmental resources that keeps all the organisms alive on earth. The ultraviolet (UV) radiation from the sun is essential for vitamin D synthesis in the human body, which is crucial for bone and muscle health. In addition, sun exposure also helps to reduce the risk of some cardiovascular diseases and cancers. However, excessive UV exposure can lead to adverse effects, including some eye diseases, premature aging, sunburn and skin cancers. The solar UV irradiance itself depends on many environmental factors. In fact, the UV index reported in weather forecasts is an estimation under cloudless conditions. Personal UV exposure also depends on one's outdoor activities and habits. Furthermore, the UV intake depends on the skin sensitivity. Therefore, there is a need for research into monitoring the optimal daily UV exposure for health benefits, without developing potential health risks. To facilitate the monitoring of solar UV intensity and cumulative dose, a variety of UV sensors have been developed in the past few decades and many are commercially available. Examples of sensors being marketed are: portable UV dosimeter, wearable UV radiometer, personal UV monitor, and handheld Solarmeter®. Some of the UV sensors can be worn as personal health monitors, which promote solar exposure protection. The paper provides a comprehensive review of the wearable and portable UV sensors for monitoring personal UV exposure, including a discussion of their unique advantages and limitations. Proposals are also presented for possible future research into reliable and practical UV sensors for personal UV exposure monitoring.

Longitudinal associations of dietary patterns with sociodemographic and lifestyle factors in older adults: the TASOAC study

BACKGROUND/OBJECTIVES

To derive dietary patterns and examine their longitudinal associations with sociodemographic and lifestyle factors in the Tasmanian Older Adult Cohort.

SUBJECTS/METHODS

This is a corrected analysis of a retracted paper. We followed 1098 adults aged ≥50 years for 5 years. Dietary intake was assessed using a validated food frequency questionnaire. Baseline dietary patterns were identified using exploratory factor analysis and scores at each time point calculated using the weighted sum score method. Associations of energy-adjusted dietary pattern scores with participant characteristics were assessed using linear mixed-effects models.

RESULTS

The four dietary patterns identified were: fruit and vegetable (vegetables, potatoes, fruits); animal protein (poultry, red meats, fish); snack (snacks, sweets, nuts); western (meat pies, hamburgers, pizzas). Fruit and vegetable pattern scores were lower in men and current smokers at baseline. Animal protein scores were lower in older and retired people but higher in men and smokers at baseline. The sex difference in animal protein score increased over time (p = 0.012). At baseline, snack score was positively associated with age and physical activity, but lower in men and current smokers. The effect of age on snack score lessened over time (p = 0.035). Western scores were lower in older people but higher in men, current smokers and those living in disadvantaged areas at baseline. The effect of age on western score reduced over time (p = 0.001).

CONCLUSIONS

The higher scores for healthy and/or lower scores for unhealthy patterns in men, smokers, retirees and those experiencing social disadvantage suggest these could be target groups for interventions to improve diet quality in older adults.

Association of vitamin D and knee osteoarthritis in younger individuals

BACKGROUND

The incidence of primary osteoarthritis knee is gradually increasing among young individuals. The increasing prevalence of obesity, sedentary lifestyle, sporting activity, and vitamin D deficiency (VDD) has been hypothesized for this shifting disease trend. This study was designed to look for the association of serum vitamin D among these young arthritic patients.

AIM

To look for the association of serum vitamin D in younger knee osteoarthritis (KOA) patients.

METHODS

In a 2-year observational study, 146 non-obese KOA patients of 35-60 years were evaluated clinically (Knee injury and Osteoarthritis Outcome Score, KOOS) and radiologically (Kellegren-Lawrence stage, KL). The serum 25(OH)D level of these patients and 146 normal healthy individuals of same age group were estimated.

RESULTS

Both the groups were comparable in terms of age and sex. The average serum 25(OH)D level in healthy individuals and KOA patients was 45.83 ng/mL and 34.58 ng/mL, respectively (P < 0.001). Inadequate serum 25(OH)D level (< 30 ng/mL) was found in 46.57% of KOA patients and 24% of normal healthy participants indicating a significant positive association (odds ratio 2.77, 95%CI: 1.67-4.54, P < 0.001). The 25(OH)D level in KL grade I, II, III and IV was 43.40, 30.59, 31.56 and 33.93 ng/mL respectively (no difference, P = 0.47). Similarly, the KOOS score in sufficient, insufficient and deficient groups were 65.31, 60.36 and 65.31, respectively (no difference, P = 0.051).

CONCLUSION

The serum 25(OH)D level is significantly low in younger KOA patients. However, the clinical and radiological severities have no association with serum vitamin D level.

Associations Between Vitamins C and D Intake and Cartilage Composition and Knee Joint Morphology Over 4 Years: Data From the Osteoarthritis Initiative

OBJECTIVE

To determine the cross-sectional and longitudinal associations of vitamin C and D intake with magnetic resonance imaging (MRI) measures of cartilage composition (T2) and joint structure (cartilage, meniscus, and bone marrow) using data from the Osteoarthritis Initiative (OAI) cohort.

METHODS

A total of 1,785 subjects with radiographic Kellgren/Lawrence knee grades 0-3 in the right knee were selected from the OAI database. Vitamins C and vitamin D intake (diet, supplements, and total) were assessed using the Block Brief 2000 Food Frequency Questionnaire at baseline. The MRI analysis protocol included 3T cartilage T2 quantification and semiquantitative joint morphology gradings (Whole-Organ Magnetic Resonance Imaging Score [WORMS]) at baseline and 4 years. Linear regression was used to assess the association between standardized baseline vitamin intake and both baseline WORMS scores and standardized cartilage T2 values.

RESULTS

Higher vitamin C intake was associated with lower average cartilage T2 values, medial tibia T2 values, and medial tibia WORMS scores (standardized coefficient range -0.07 to -0.05, P < 0.05). Higher vitamin D intake was associated with a lower cartilage WORMS sum score and medial femur WORMS score (standardized coefficient range -0.24 to -0.09, P < 0.05). Consistent use of vitamin D supplements of 400 IU at least once a week over 4 years was associated with significantly less worsening of cartilage, meniscus, and bone marrow abnormalities (odds ratio range 0.40-0.56, P < 0.05).

CONCLUSION

Supplementation with vitamin D over 4 years was associated with significantly less progression of knee joint abnormalities. Given the observational nature of this study, future longitudinal randomized controlled trials of vitamin D supplementation are warranted.

Sunlight exposure, sun-protective behaviour, and anti-citrullinated protein antibody positivity: A general population-based study in Quebec, Canada

OBJECTIVES

To examine associations between sunlight exposure and anti-citrullinated protein antibodies (ACPA) using general population data in Quebec, Canada.

METHODS

A random sample of 7600 individuals (including 786 positive ACPA subjects and 201 self-reported rheumatoid arthritis, RA cases) from the CARTaGENE cohort was studied cross-sectionally. All subjects were nested in four census metropolitan areas, and mixed-effects logistic regression models were used to calculate odds ratios (OR) and 95% confidence intervals (CIs) for ACPA positivity related to sunlight exposure, adjusting for sun-block use, industrial fine particulate matter (PM_2.5 ) exposures, smoking, age, sex, French Canadian ancestry, and family income. We also performed sensitivity analyses excluding subjects with RA, defining ACPA positivity by higher titers, and stratifying by age and sex.

RESULTS

The adjusted ORs and 95% CIs did not suggest conclusive associations between ACPA and sunlight exposure or sun-block use, but robust positive relationships were observed between industrial PM_2.5 emissions and ACPA (OR 1.19 per µg/m³ , 95% CI 1.03 - 1.36 in primary analyses).

CONCLUSIONS

We did not see clear links between ACPA and sunlight exposure or sun-block use, but we did note positive associations with industrial PM_2.5 . Future studies of sunlight and RA (or ACPA) should take air pollution exposures into account.

Association between serum Vitamin D deficiency and Knee Osteoarthritis

Objective:

Levels of Vitamin D may influence the development of knee osteoarthritis (OA), which is one of the most common joint diseases. The aim of this study was to investigate the association between serum Vitamin D deficiency and knee OA in Ardabil and Iran.

Methods:

One hundred fifty-eight consecutive patients referred to rheumatology clinic of Ardabil City Hospital were recruited in the study. All the participants underwent x-rays in two anterior-posterior and side views of the knees. Staging of knee OA was done according to Kellgren-Lawrence criteria. Seventy-nine individuals with clinical and radiographic signs of knee OA were defined as the case group, and those without clinical and radiographic signs of the disease were defined as a control group. Haematology and biochemical profile including measurement of 25-hydroxyvitamin D serum level was performed in the participants.

Results:

The mean age of patients and controls were 54.12 ± 4.67 and 55.37 ± 5.12 years, respectively. The average serum vitamin D in OA patients and controls were 26.8±6.2 ng/ml and 28.1±5.3ng/ml, respectively (p=0.36). There was a significant association between serum vitamin D and staging of knee OA (p=0.001). Based on vitamin D levels, most of patients with vitamin D deficiency were in stages III and IV.

Conclusion:

The findings of the study suggest that vitamin D deficiency should be considered in patients with OA and treated accordingly.

Association between Vitamin D and Knee Osteoarthritis: A PRISMA-Compliant Meta-analysis

BACKGROUND

Previous investigations showed inconsistent results for associations between vitamin D and knee osteoarthritis (OA). The present study aimed to make a systematic review and meta-analysis for the association between vitamin D and knee OA.

METHODS

We systematically searched for articles published in the databases PubMed, Web of Science, EMBASE, Medline, and Google Scholar through July 2019. All statistical analyses were made using STATA 12.0 software. The Q test and I² were applied to examine heterogeneities between studies.

RESULTS

The study indicated that there were no significant associations between serum levels of 25-hydroxy (OH) vitamin D and prevalence, incidence or progression of knee radiographic OA (ROA), and joint space narrowing (JSN). However, a subgroup study showed significant associations of low vitamin D levels with the progression of knee OA. Additionally, the present study showed no significant effect of vitamin D supplementation on knee OA.

CONCLUSIONS

The results do not support that serum levels of 25(OH) vitamin D are associated with the risks of knee OA, except perhaps with progression of knee OA. In addition, vitamin D supplementation may not have a clinically significant effect on pain control or structure (tibial cartilage volume and JSW) progression in patients with knee OA. Longer-term clinical trials are essential to explore the effect of vitamin D supplementation on knee OA.

Associations between suprapatellar pouch effusion-synovitis, serum cartilage oligomeric matrix protein, high sensitivity C-reaction protein, knee symptom, and joint structural changes in patients with knee osteoarthritis

OBJECTIVES

To investigate the cross-sectional associations between suprapatellar pouch effusion-synovitis and serum levels of cartilage oligomeric matrix protein (COMP), high sensitivity C-reaction protein (hs-CRP), knee symptom, and structural changes in patients with symptomatic knee osteoarthritis (OA).

METHOD

A total of 173 subjects were included. The osteophytes, joint space narrowing (JSN), and radiographic severity of OA were determined using X-ray. Cartilage defects, bone marrow lesions (BMLs), and suprapatellar pouch effusion-synovitis were assessed using magnetic resonance imaging. Serum levels of COMP and hs-CRP were measured by enzyme-linked immunosorbent assay. The knee joint symptom was self-reported using visual analogue scale.

RESULTS

In this OA cohort, after adjustment for age, sex, and BMI, the presence of pathological effusion-synovitis was associated with serum levels of COMP (β: 30.98, P = 0.018), and suprapatellar pouch effusion-synovitis maximum areas were associated with serum hs-CRP levels. Both suprapatellar pouch effusion-synovitis maximum area and grade were associated with osteophytes and Kellgren-Lawrence scores (ORs: 1.29-1.54, all P < 0.05). In patients with high tertile of hs-CRP, both suprapatellar pouch effusion-synovitis maximum area and grade were associated with cartilage defects at lateral and medial tibiofemoral sites (ORs: 3.01-8.41, all P < 0.05) after adjustment for covariates. In female patients, the significant associations were present between suprapatellar pouch effusion-synovitis and medial tibiofemoral BMLs (ORs: 1.43-1.53, all P < 0.05) after adjustment for covariates.

CONCLUSIONS

Suprapatellar pouch effusion-synovitis was associated with serum levels of COMP as well as hs-CRP and knee structural abnormalities in patients with knee OA. These suggested that effusion-synovitis may play a role in knee OA.Key Points• Suprapatellar pouch effusion-synovitis is associated with serum levels of COMP in patients with knee OA.• Suprapatellar pouch effusion-synovitis is associated with cartilage defects in knee OA patients with high systemic inflammation.

Therapeutic and Preventive Potential of Vitamin D Supplementation in Knee Osteoarthritis

Objective

Vitamin D deficiency is linked with pain, function, and radiographic progression of knee osteoarthritis (KOA), but the results of studies addressing the association and effect of vitamin D supplementation for pain, function, quality of life, radiographic disease, and progression are inconsistent. The aim of this review is to determine the therapeutic and preventive potential of vitamin D supplementation in KOA.

Method

Eligible pertinent English language studies published in 2000 and thereafter in Medline/PubMed, Scopus, and Google Scholar were selected by using keywords that include “knee osteoarthritis,” “vitamin D supplementation,” “pain,” “structural abnormalities,” “treatment,” and “progression.”

Results

The results of a few studies showed a preventive potential for vitamin D in KOA, but most of the randomized clinical trials that assessed the therapeutic efficacy of vitamin D supplementation in KOA found no clear therapeutic effect, with the exception of one study that found a small but significant effect of vitamin D on pain and knee function. Nonetheless, the results of a few longitudinal studies as well as systematic reviews are promising and thus encourage further studies. Inconsistent results on the effect of vitamin D on KOA may be attributed to factors such as severity of KOA, baseline level of serum vitamin D, duration of treatment, and vitamin D dosages.

Conclusion

Given the multiple skeletal and extraskeletal benefits of vitamin D supplementation in elderly people, the issue of vitamin D supplementation in KOA requires further study to elucidate the dosage and duration of treatment that provides the most effective therapeutic effect.

Vitamin D and Vitamin D Receptor Gene in Osteoarthritis

Osteoarthritis is a degenerative, painful and irreversible disease that affects millions of people worldwide. The causes and mechanisms of osteoarthritis have not been fully understood. Vitamin D is an essential factor in bone metabolism. Its actions are mediated by the vitamin D receptor, a transcription factor that controls gene expression, thus maintaining calcium and phosphate homeostasis. Vitamin D has been hypothesized to play essential role in a number of musculoskeletal diseases including osteoarthritis, and its deficiency is prevalent among osteoarthritis patients. A large number of studies have been done regarding the effects of vitamin D in pathogenesis and progression of osteoarthritis, as well as its use a therapeutic agent. Up to date, studies have provided controversial results, and no consensus concerning this matter was achieved. With this review, we aim to explore current data on the possible role of vitamin D and its receptor in pathogenesis of osteoarthritis and assess the efficiency of vitamin D supplementation as a therapeutic strategy.

Vitamin D in the Prevention and Treatment of Osteoarthritis: From Clinical Interventions to Cellular Evidence

Older adults are recommended vitamin D to prevent fractures. Though this population is also at risk of osteoarthritis (OA), the effect of vitamin D on OA is unclear and may differ by disease state. The relationship between vitamin D and OA during OA initiation and progression were considered in this narrative review of in vivo and in vitro studies. Regarding OA initiation in humans, the small number of published observational studies suggest a lack of association between induction of OA and vitamin D status. Most randomized controlled trials were performed in White OA patients with relatively high vitamin D status (>50 nmol/L). These studies found no benefit of vitamin D supplementation on OA progression. However, subset analyses and one randomized controlled pilot trial indicated that vitamin D supplementation may alleviate joint pain in OA patients with low vitamin D status (<50 nmol/L). As the etiology of OA is recently being more fully uncovered, better animal and cell models are needed. According to currently available clinical results, evidence is lacking to set a vitamin D level to prevent OA, and increasing vitamin D status above 50 nmol/L does not seem to benefit OA patients.

Does vitamin D deficiency influence the incidence and progression of knee osteoarthritis? - A literature review

OBJECTIVES

Vitamin D has been believed to have a bearing in the pathogenesis of knee osteoarthritis (OA). This study was done to search the literature and review the correlation between vitamin D levels in knee OA in the adult population and the outcome of vitamin D supplementation in knee OA.

METHODS

An exhaustive search of Pub Med and Cochrane library database was done with keywords vitamin D, knee and osteoarthritis for a period from Jan 2005 to December 2015. All Randomized Control Trials (RCT), Cohort, Case-control, cross-sectional studies were included in the present systematic review.

RESULTS

The search resulted in a total of 86 studies; out of which 11 studies were included in the current review. There were two Randomized Control Trial (RCT), one case-control, four cross-sectional and four cohort studies. These studies comprised of a total of 5137 participants (ranging from 46 to 1248) Our results suggested there was a moderate evidence of positive association in vitamin D deficiency (VDD) and progression of radiographic OA (ROA), as assessed by Kellgren and Lawrence (KL) grading. However, VDD was not associated with the incidence of ROA and MRI-detected change in focal cartilage defect. However, this study has a limited evidence for a positive correlation in VDD and the cartilage volume loss. There was also limited evidence showing no role of vitamin D therapy in reducing cartilage volume loss and knee pain in Knee OA.

CONCLUSION

The VDD is common and has been associated with knee OA, in an adult population. However, there is still inconsistent evidence regarding the prevention of incidence and progression of ROA after vitamin D therapy. There is a need for multicentric and well-conducted randomized studies with larger samples to conclude the positive effect of Vitamin D therapy.

Use of Vitamin D Supplements in Osteoarthritis: An Observational Study in a Tertiary Health Care Facility

OBJECTIVE

The purpose of the study was to assess impact of vitamin D supplements on the disease progression and overall health of osteoarthritis (OA) patients.

METHODOLOGY

A cohort study was carried out for 8 months (August 2017-March 2018) in the Orthopedics Department of Kasturba Hospital, Manipal, India, a tertiary care hospital. One hundred and forty-two patients who were diagnosed with OA (grades 1-3) with low serum 25(OH)D levels (severely deficient, deficient, or insufficient) were selected for the study. These patients were categorized into two cohorts: a control cohort (CC) and a study cohort (SC). CC members were patients (n = 71) who had not received vitamin D supplements, and SC members were patients (n = 71) who had received vitamin D supplements. Severity grading of OA, pain score, and health assessment were performed using the Kellgren-Laurence grading score, visual analogue scale (VAS), and WOMAC, respectively, at baseline and after 3 months of follow-up.

RESULTS

Subjects in the both CC and SC reported no statistically significant difference (similar in both group) in severity grade (p = 0.303), pain score (p = 0.099), parathyroid hormone (PTH) (p = 0.083), and health status (p = 0.76) at baseline. After 3 months of follow-up (post vitamin D supplementation), OA patients have shown statistically significant difference in severity grades, serum 25(OH)D status, PTH level (p < 0.001), and overall health status (p = 0.001) in the SC with respect to baseline. Likewise, percentage distribution of positive changes was significantly higher in severity grade, pain score, serum 25(OH)D level, overall health status (p < 0.001), and PTH (p = 0.040) of SC as compared to CC at follow-up.

CONCLUSION

Vitamin D supplements have significantly improved serum 25(OH)D levels, PTH, severity grade, and pain score of OA patients. Most importantly, vitamin D supplements have shown improvement in the overall health of OA patients, emphasizing the place of vitamin D supplements in the management of OA. Clinical Trial Registry-India (CTRI) registration no: CTRI/2017/12/011031.

Biochemical changes associated with temporomandibular disorders

OBJECTIVE

To assess vitamin D, parathyroid hormone, calcitonin, calcium, phosphorus and magnesium levels in patients with versus without temporomandibular disorders (TMDs).

METHODS

This prospective observational study included patients with TMDs and age-matched healthy controls. TMDs were diagnosed via physical and radiologic examination, and serum levels of 25 (OH) vitamin D, parathyroid hormone, calcitonin, calcium, magnesium, and phosphorus were determined. The impact of age, sex and seasonal variations in serum 25 (OH) vitamin D levels was controlled by the inclusion of age, sex and date-matched control patients.

RESULTS

The study included 100 patients, comprising 50 patients with TMDs and 50 control patients. No statistically significant between-group differences were found regarding age or sex. No statistically significant between-group differences were found in terms of serum 25 (OH) vitamin D, calcitonin, calcium, magnesium or phosphorus levels. Parathyroid hormone levels were statistically significantly higher in patients with TMDs versus healthy control patients.

CONCLUSION

In patients with temporomandibular disorders, increased parathyroid hormone levels in response to vitamin D deficiency was significantly more prominent. These data suggest that, in patients with temporomandibular disorders, vitamin D deficiency should be assessed and corrected.

Vitamin D Intake and Magnetic Resonance Parameters for Knee Osteoarthritis: Data from the Osteoarthritis Initiative

PURPOSE

There is evidence that vitamin D may play a role in the osteoarthritis (OA) pathogenesis, but the few data available are limited to X-rays and clinical findings. The aim of this study was to investigate whether a higher intake of vitamin D was associated with a better architecture of the cartilage of the knee, assessed with magnetic resonance (MRI), in a large cohort from North America.

METHODS

783 participants (59.8% females; mean age: 62.3 years) with an MRI assessment from the Osteoarthritis Initiative were included. Vitamin D dietary intake was calculated as the sum of food and oral supplementation. A coronal 3D FLASH with Water Excitation MR sequence of the right knees was used. The strength of the association between dietary vitamin D intake and knee MRI parameters was investigated through an adjusted linear regression analysis, reported as standardized betas with 95% confidence intervals (CIs).

RESULTS

Using a linear regression analysis, adjusted for ten potential confounders, higher vitamin D intake (reported as an increase in one standard deviation, = 250 IU) corresponded to significantly higher values of mean cartilage thickness and volume of cartilage at medial tibia, volume of cartilage and mean cartilage thickness at central lateral femur, volume of cartilage and mean cartilage thickness at central medial femur, and volume of cartilage and mean cartilage thickness at central medial tibial-femoral compartment.

CONCLUSIONS

Higher vitamin D intake is associated with a significantly better architecture of the cartilage of the knee, also independently taking in account from several potential confounders.

Association between vitamin D concentrations and knee pain in patients with osteoarthritis

Objectives

Osteoarthritis (OA) and vitamin D deficiency are common health conditions in older people. Whether vitamin D concentration is associated with knee OA is controversial. In this study, we aimed to determine the association between serum concentrations of vitamin D and osteoarthritic knee pain.

Subjects and Methods

Vitamin D concentrations were measured with the 25 hydroxyvitamin D test in patients presenting with clinical symptoms of primary knee osteoarthritis. Osteoarthritis was graded on the Kellgren-Lawrence grading scale from anteroposterior and lateral radiographs. Height, weight, and body mass index (BMI) were recorded. Patients completed a 10-cm visual analogue scale (VAS) for indicating pain and the Western Ontario and McMaster Universities Arthritis Index (WOMAC). Vitamin D concentration was defined as severely deficient (<10 ng/mL), insufficient (10 to 19 ng/mL), or normal (20 to 50 ng/mL).

Results

Of 149 patients (133 women), the mean age was 63.6 years. Mean vitamin D concentration was 11.53 ng/mL, and 90% patients were vitamin D deficient. Mean WOMAC score was 57.2, and VAS pain score was 7.5. Kellgren-Lawrence grade was 2 for 10 patients, grade 3 for 61, and grade 4 for 88. Mean BMI was 33.4. Mean values of VAS, WOMAC, and BMI did not differ by vitamin D status.

Conclusion

Serum vitamin D concentration is not associated with knee pain in patients with osteoarthritis.

Do vitamin D levels affect the clinical prognoses of patients with knee osteoarthritis?

OBJECTIVE

Although vitamin D deficiency has been associated with osteoporosis, as well as fractures, in elderly men and women, the role of vitamin D deficiency in the pathogenesis of osteoarthritis (OA) remains controversial. In this study, we aimed to investigate the effects of vitamin D deficiency on the functional status and disease prognosis of patients with knee osteoarthritis.

PATIENTS AND METHODS

Our study comprised 100 patients that met the American College of Rheumatology criteria for a diagnosis of knee osteoarthritis. Each patient underwent knee radiography, the results of which were graded according to Kellgren and Lawrence radiographic grading scale; those that met the diagnostic criteria were included in the study. The visual analog scale (VAS), Nottingham Health Profile (NHP), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Lequesne Knee Osteoarthritis Index were used to assess patients' pain, function and quality of life. Complete blood counts, sedimentation rates and serum C-reactive protein, rheumatoid factor, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, sodium, potassium, calcium, phosphorus, parathyroid and thyroid hormone levels were routinely recorded for each patient. Vitamin D levels were analyzed in winter (between November and February) using high performance liquid chromatography.

RESULTS

Patients were divided into two groups, Group 1 and Group 2, according to the presence or absence of vitamin D deficiency. The groups did not differ significantly in terms of age, disease duration, sex distribution, presence of osteoporosis or radiographic stage of knee osteoarthritis (p = 0.793, 0.092, 0.250, 0.835 and 0.257, respectively). However, the NHP pain, physical activity, fatigue, social isolation, and emotional reactions subsets, WOMAC pain and physical function subsets and total score, Lequesne knee osteoarthritis index, and patient/physician VAS scores were significantly higher in Group 1 than in Group 2 (p < 0.05).

CONCLUSIONS

Our study therefore suggests that vitamin D deficiency exacerbates pain, dysfunction and a poorer quality of life in patients with knee osteoarthritis. Further longer-term studies are needed to investigate the effects of vitamin D deficiency on OA-related symptoms.

Associations between MRI-detected early osteophytes and knee structure in older adults: a population-based cohort study

OBJECTIVES

To describe prevalence of osteophytes (OPs) detected only by magnetic resonance imaging (MRI) but not by standard X-ray in older adults and to evaluate longitudinal associations with knee structural changes.

METHODS

837 participants were randomly selected from the local community and had MRI scans to assess knee OPs and other structures. OPs detected only by MRI but not by standard X-ray were defined as MRI-detected early OPs (MRI-OPs for short). OPs detected by both MRI and X-ray were defined as established-OPs.

RESULTS

The prevalence of MRI-OPs was 50% while the prevalence of established-OPs was 10% and no-OPs was 40% at total tibiofemoral (TF) compartment at baseline. Compared with no-OPs, participants with MRI-OPs had greater risks of increased cartilage defects in all TF compartments (RR 1.37, 95%CI 1.07-1.74) and bone marrow lesions (BMLs) only in medial TF compartment (RR 1.49, 95%CI 1.06-2.11), after adjustment for age, sex, BMI, cartilage defects, BMLs and/or joint space narrowing; participants with established-OPs had greater cartilage volume loss at total (β -2.02, 95%CI -3.86, -0.17) and lateral tibial sites (β -5.63, 95%CI -9.93, -1.32), greater risks of increased cartilage defects in total (RR 1.66, 95%CI 1.15-2.40) and medial TF compartments (RR 1.49, 95%CI 1.20-1.69) and BMLs in all TF compartments (RR 1.88, 95%CI 1.22-2.89), after adjustment for covariates.

CONCLUSION

MRI-OPs were associated with changes in knee structures, and the associations were similar but not as prominent as those for established-OPs. These suggest MRI-OPs may have a role to play in knee early-stage osteoarthritic progression.

Skeletal muscle vitamin D in patients with end stage osteoarthritis of the knee

Muscle function is often impaired in patients with knee osteoarthritis (OA), with reduced strength and increased pain. The role of vitamin D and the vitamin D-endocrine pathway in muscle health has recently been placed in the spotlight, with various groups reporting positive effects on muscle development, function and health. Recently, it has been shown that uptake into muscle of the specialized vitamin D binding protein (DBP) is dependent on the endocytic receptor, megalin. Here we analyse circulating vitamin D, and muscle DBP, megalin and the cognate vitamin D receptor (VDR) in patients with knee OA and compare them to asymptomatic controls. Muscle and blood samples were collected from 19 patients with end-stage OA of the knee and 10 age-matched controls. Muscle biopsies from the OA group were performed during knee replacement surgery and a needle biopsy was used on control volunteers. Immunoblots performed with specific antibodies were used to detect the presence of DBP, megalin, VDR (using the specific D-6 antibody) and albumin in the muscle biopsies. Results were correlated with FoxO1, a key regulator of the ubiquitin-proteasome degradation pathway in muscle. There were no differences in circulating levels of 25 (OH) vitamin D3 between the groups, and no subjects were vitamin D deficient. We found increased VDR, DBP and albumin protein in the muscle from patients with OA compared to controls, with no change in muscle megalin expression. Furthermore, DBP levels in the muscle correlated with FoxO1, suggesting an association between muscle protein breakdown and the activation of the vitamin D-endocrine pathway in muscle surrounding an OA affected joint. We show, for the first time, that the factors involved in the vitamin D-endocrine-pathway are present at higher levels in muscles from OA patients compared to asymptomatic controls. This is despite no differences in circulating 25 (OH) vitamin D levels between the groups. These findings indicate the activation of vitamin D pathway in these muscles that may provide a beneficial compensatory stimulation of the repair process in muscles that are subject to inflammatory and proteolytic processes.

Maintaining Vitamin D Sufficiency Is Associated with Improved Structural and Symptomatic Outcomes in Knee Osteoarthritis

BACKGROUND

The aim of this study was to describe whether maintaining sufficient serum vitamin D levels in people with knee osteoarthritis and baseline vitamin D insufficiency has an association with change in knee structures and symptoms over 2 years.

METHODS

Participants (n = 413, mean age 63.2 years) with symptomatic knee osteoarthritis and vitamin D insufficiency were enrolled in a clinical trial. In all, 340 participants (82.3%) completed the study, with 25-hydroxyvitamin D [25(OH)D] measurements at baseline and months 3 and 24. Participants were classified as consistently insufficient [serum 25(OH)D ≤50 nmol/L at months 3 and 24, n = 45], fluctuating [25(OH)D >50 nmol/L at either point, n = 68), and consistently sufficient [25(OH)D >50 nmol/L at months 3 and 24, n = 226] groups. Knee cartilage volume, cartilage defects, bone marrow lesions, and effusion-synovitis volume were assessed using MRI at baseline and month 24. Knee symptoms were assessed at baseline and months 3, 6, 12, and 24 using the Western Ontario and McMaster Universities Arthritis Index.

RESULTS

The consistently sufficient group had significantly less loss of tibial cartilage volume (β 2.1%; 95% confidence interval [CI], 0.3%, 3.9%), less increase in effusion-synovitis volume (β -2.5 mL; 95 CI%, -4.7, -0.2 mL), and less loss of Western Ontario and McMaster Universities Arthritis Index physical function (β -94.2; 95% CI, -183.8, -4.5) compared with the consistently insufficient group in multivariable analyses. In contrast, there were no significant differences in these outcomes between the fluctuating and consistently insufficient groups. Changes in cartilage defects, bone marrow lesions, and knee pain were similar between groups.

CONCLUSION

This post hoc analysis suggests beneficial effects of maintaining vitamin D sufficiency on cartilage loss, effusion-synovitis, and physical function in people with knee osteoarthritis.

The effect of vitamin D status on pain, lower limb strength and knee function during balance recovery in people with knee osteoarthritis: an exploratory study

The association between vitamin D and muscle function associated with balance recovery and falls in people with knee osteoarthritis is unclear. Those with vitamin D insufficiency demonstrated poorer knee function during balance recovery, greater pain and locomotor dysfunction. Vitamin D insufficiency may have an adverse effect on muscle power function.

PURPOSE

Low vitamin D status in people with knee osteoarthritis (OA) is often reported to be associated with increased pain and locomotor dysfunction. However, despite the growing evidence of the effect of vitamin D on the pathogenesis of knee OA, its role remains conflicting. Importantly, muscle function is important for knee joint health; however, the association between vitamin D levels and muscle function associated with balance recovery and falls is unclear. This study investigated the effect of circulating 25-hydroxyvitamin D (25 (OH) D) on pain, quadriceps strength, lower limb muscle mass and knee power function during balance recovery in people with knee OA.

METHODS

Twenty-four participants with clinical symptoms of knee OA (68.6 ± 6.2 years) participated in the study. Serum levels of 25 (OH) D were assessed and participants were classified as follows: vitamin D insufficiency ≤ 50 nmol/L and vitamin D sufficiency > 50 nmol/L. The groups were compared on knee function during balance recovery tasks, lower limb strength and muscle mass as well as perceived pain and function.

RESULTS

Seven patients (29.1%) were classified as vitamin D-insufficient. Vitamin D insufficiency was associated with reduced knee muscle function during the balance recovery task, increased pain (Western Ontario and McMasters University Osteoarthritis Index (WOMAC) subscore), dysfunction (WOMAC subscore) and total WOMAC score (p < 0.05).

CONCLUSION

People with knee OA with vitamin D insufficiency demonstrated poorer knee function during balance recovery, greater pain and locomotor dysfunction. Vitamin D insufficiency may have an adverse effect on muscle power function.

The effect of vitamin D supplementation on knee osteoarthritis: A meta-analysis of randomized controlled trials

OBJECTIVE

We conducted a meta-analysis of RCTs to evaluate the effects of vitamin D supplementation in the prevention of symptom and structural progression of knee OA.

METHODS

PubMed, Embase, and Web of Science databases were searched to identify relevant studies. Outcomes included Western Ontario and McMaster Universities Arthritis Index (WOMAC) pain, function, stiffness, tibial cartilage volume, and serum vitamin D3 levels, and adverse events. Results were expressed as weight mean difference (WMD) with 95% confidence interval (CI), and risk ratio (RR) with 95%CI.

RESULTS

Four RCTs involving 1136 patients were included in this study. Pooled estimates suggested that vitamin D supplementation was associated with a significant reduction in WOMAC pain, and WOMAC function, but not in WOMAC stiffness. Vitamin D supplementation increased the serum vitamin D3 level, but had no effect on tibial cartilage volume. Subgroup analysis showed that, a daily supplement of more than 2000 IU vitamin D significantly decreased the WOMAC pain and WOMAC function. There was no significant difference in incidence of adverse events between the vitamin D and placebo groups.

CONCLUSION

Vitamin D supplementation was effective in improving the WOMAC pain and function in patients with knee OA. However, it had no beneficial effect on the prevention of tibial cartilage loss. Therefore, there is currently a lack of evidence to support the use of vitamin D supplementation in preventing the progression of knee OA.

Associations between endogenous sex hormones and MRI structural changes in patients with symptomatic knee osteoarthritis

OBJECTIVE

To investigate the longitudinal association between endogenous sex hormones and knee osteoarthritis (OA) structures and pain.

METHOD

We examined 200 participants (mean age 63.0 ± 7.3 years) from a clinical trial of vitamin D supplement for symptomatic knee OA. Serum levels of estradiol, progesterone, testosterone and sex hormone binding globulin (SHBG) were analyzed at baseline and 24 months later. Magnetic resonance imaging (MRI) scans of selected knee were obtained at both baseline and follow-up for the measurement of cartilage volume, cartilage defects, bone marrow lesions (BMLs) and effusion-synovitis volume. Knee pain was assessed using a 100 mm visual analogue scale (VAS). Longitudinal data were analyzed using linear mixed-effects model.

RESULTS

One hundred and seven males and 93 females were included in this study. For females, after adjustment for age, body mass index (BMI), and vitamin D level, progesterone was positively associated with cartilage volume (β = 0.12 mm³ per quartile, P < 0.01). Estradiol levels were associated with lower grades of BMLs (β = -0.46 per quartile, P = 0.03), while estradiol (β = -1.28 per quartile, P = 0.04), progesterone (β = -1.56 per quartile, P < 0.01) and testosterone (β = -1.51 per quartile, P = 0.01) were inversely associated with effusion-synovitis volume. Testosterone was inversely associated with knee pain. No consistent associations were observed for males.

CONCLUSION

In women but not men, low serum levels of endogenous estradiol, progesterone and testosterone are associated with increased knee effusion-synovitis and possibly other OA-related structural changes. This may contribute to observed sex differences in knee OA.

The relationship between cumulative lifetime ultraviolet radiation exposure, bone mineral density, falls risk and fractures in older adults

Data linking cumulative lifetime vitamin D status with skeletal outcomes are lacking. We show that increasing cumulative sun exposure was associated with higher bone mineral density in younger males and protective against fractures in females independent of current vitamin D. This supports the concept that cumulative sun exposure is an important contributor to skeletal health.

INTRODUCTION

While low 25-hydroxyvitamin D levels are associated with increased fracture risk, this reflects only recent sun exposure. The Beagley-Gibson (BG) method utilises microtopographical skin changes to quantify cumulative lifetime ultraviolet radiation (sun) exposure. This study aimed to describe the relationship between BG grade, BMD, falls risk and fractures in older adults.

METHODS

Eight hundred thirty-five community-dwelling adults aged 53-83 years had silicone casts from the dorsum of both hands graded by the BG method. BMD was measured using DXA and falls risk using the short form of the Physiological Profile Assessment. Vertebral deformities and symptomatic fractures were assessed by DXA and questionnaire, respectively.

RESULTS

The relationship between BG grade, spine BMD and vertebral fracture varied depending upon sex. In females, increasing grade was associated with lower vertebral fracture prevalence (OR = 0.44/grade, p = 0.018) and fewer fractures (OR = 0.82/grade, p = 0.021), particularly major fractures (OR = 0.75/grade, p = 0.03). In males, increasing grade was associated with more DXA-detected vertebral deformities (RR = 1.28/grade, p = 0.001), but not symptomatic fractures. These relationships were independent of BMD, falls risk, smoking and current 25-hydroxyvitamin D. BG grade was not associated with falls risk. For BMD, there were interactions between BG grade and both age and sex and a positive trend with hip BMD in younger males.

CONCLUSIONS

BG grade demonstrated beneficial associations with fracture outcomes in females and BMD in younger males independent of current 25-hydroxyvitamin D. These data support the concept that cumulative ultraviolet radiation exposure is an important determinant of skeletal health. The association with vertebral deformities in males may reflect outdoor physical trauma in younger life.

Vitamin D supplementation for the management of knee osteoarthritis: a systematic review of randomized controlled trials

Conflicting evidence exists concerning the supplementation of vitamin D in knee osteoarthritis condition. This systematic literature review was done to explore the effects of vitamin D supplementation in the management of knee osteoarthritis. Electronic literature search was done in databases like PubMed^®, Embase^®, and Cochrane CENTRAL from inception to 6th July 2016. The quality of included Randomized Controlled Trials (RCTs) was assessed using Cochrane risk of bias tool. We considered change in Western Ontario and McMaster Universities (WOMAC) index, Visual Analog Scale (VAS) and Functional Pain Score (FPS) as the primary outcome measure. Change in tibial cartilage thickness, joint space width and safety profile was considered as secondary outcomes. Participants were randomized either to treatment or placebo group. Participants received cholecalciferol as an intervention through oral route in the dose range of 800-60,000 IU except in the one study where participants received ergocalciferol. All included RCTs showed a significant increase in serum vitamin D level in the treatment group compared to the placebo group at the end point. No significant reduction in pain and function was reported on WOMAC scale except in one study. No significant difference was reported for WOMAC stiffness in any study. VAS was assessed in three studies in which two showed statistically significant improvement in knee pain. Three of the RCTs reported safety data with one incidence of calculus ureteric and hip fracture found to be related to the drug. The study found evidence from RCTs to be insufficient to support the use of vitamin D supplementation for patients with knee osteoarthritis.

Effect of vitamin D levels on radiographic knee osteoarthritis and functional status

Objectives

This study aims to investigate the effect of serum levels of 25 hydroxyvitamin D (25(OH)D) in patients with primary knee osteoarthritis (OA) and to assess its relationship with the radiographic grading and functional status.

Patients and methods

Serum 25(OH)D levels were measured in 107 patients (90 females, 17 males; mean age 63.0±9.6 years; range, 40 to 86 years) with primary knee OA. Radiographic grading was based on the Kellgren-Lawrence Grading Scale and the Osteoarthritis Research Society International (OARSI) Atlas Grading Scale, while the functional status was assessed using the Lequesne indices and Turkish version of the Knee Injury and Osteoarthritis Outcome Score-Physical Function Short-Form (KOOS-PS). Pain was evaluated using the Visual Analog Scale for Pain (VAS-Pain). Data including age, sex, disease duration, body mass index (BMI), and pain severity were recorded.

Results

The mean 25(OH)D level was 13.4±10.6 ng/mL, and 90 patients (84.1%) had vitamin D deficiency. The presence of severe osteophytes was observed in 67 patients (62.6%) and 85 patients (79.4%) had Grade 2-3 joint space narrowing (JSN). The mean KOOS-PS and Lequesne scores were 40.1±12.3 and 12.9±3.6, respectively. There was no correlation between serum 25(OH)D levels and functional status.

Conclusion

Our study results show that serum 25(OH)D level is not related to the severity of the radiographic knee OA grading or to the functional assessment. Age and BMI are the factors affecting the radiological knee OA severity, while age, sex, BMI, and pain severity are the main determinants of the functional status.