Sex differential impact of comorbidities in spondyloarthritis: data from COMOSPA study

OBJECTIVES

To describe and compare the prevalence of comorbidities in female and male patients with spondyloarthritis (SpA) and to assess whether comorbidities had a different impact on disease outcomes in male and female patients.

METHODS

This is a post hoc analysis of the COMOrbidities in SPondyloArthritis study. Differences in comorbidities regarding sex were assessed using logistic regression models. Comorbidities were evaluated for their impact on disease outcomes (Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Ankylosing Spondylitis Disease Activity Score (ASDAS), Bath Ankylosing Spondylitis Functional Index, European health-related quality of life questionnaire) with linear models, which included sex and comorbidity as explanatory variables and their interaction. Age and treatment with biological synthetic disease-modifying antirheumatic drugs were included as confounders.

RESULTS

We included 3982 patients with SpA (65% male, mean age 43.6 years). Male and female patients with SpA exhibited similar comorbidity profiles, except for a low prevalence of fibromyalgia in males and a higher prevalence of certain cardiovascular risk factors in males (hypertension, dyslipidaemia, renal impairment and ischaemic heart disease). Comorbidities, especially fibromyalgia, correlated with higher disease activity, decreased physical function and reduced health-related quality of life in both sexes. Some comorbidities exhibited sex-specific associations with disease outcomes. Peptic ulcers and high waist circumference had a greater impact on disease activity in females (with a higher impact in BASDAI than in ASDAS). In contrast, osteoporosis had a more pronounced effect on physical function in male patients.

CONCLUSIONS

Comorbidities exert distinct influences on disease activity, physical function and health-related quality of life in male and female patients with SpA. Understanding these sex-specific effects is crucial for improving SpA management, emphasising the importance of assessing disease activity using ASDAS when comorbidities are present to mitigate sex-related disparities in disease assessment.

Contribution of major economies to global GDP and product reallocation around the world

Economic globalization has led to production increasingly becoming concentrated in certain regions and countries of the world. This article develops an accounting framework to provide the trends for the contribution of countries to global gross domestic production (GDP). In particular, the method transforms the multiregional input-output model to quantify the relative importance of individual economies to world GDP. The proposal uses a world input-output database that distinguishes between three main economic areas: China, the United States of America and the European Union. The results suggest that identical changes in sectoral demand asymmetrically modify the relative contributions from individual economies, with China showing the highest positive (negative) impact after an increase (decrease) in world demand. These findings suggest that a generalized economic expansion (contraction) is linked to a boost (decline) in the asymmetries of production across the world.

Specific-cytokine associations with outcomes in knee osteoarthritis subgroups: breaking down disease heterogeneity with phenotyping

BACKGROUND

Despite existing extensive literature, a comprehensive and clinically relevant classification system for osteoarthritis (OA) has yet to be established. In this study, we aimed to further characterize four knee OA (KOA) inflammatory phenotypes (KOIP) recently proposed by our group, by identifying the inflammatory factors associated with KOA severity and progression in a phenotype-specific manner.

METHODS

We performed an analysis within each of the previously defined four KOIP groups, to assess the association between KOA severity and progression and a panel of 13 cytokines evaluated in the plasma and synovial fluid of our cohort's patients. The cohort included 168 symptomatic female KOA patients with persistent joint effusion.

RESULTS

Overall, our analyses showed that associations with KOA outcomes were of higher magnitude within the KOIP groups than for the overall patient series (all p-values < 1.30e-16) and that several of the cytokines showed a KOIP-specific behaviour regarding their associations with KOA outcomes.

CONCLUSION

Our study adds further evidence supporting KOA as a multifaceted syndrome composed of multiple phenotypes with differing pathophysiological pathways, providing an explanation for inconsistencies between previous studies focussed on the role of cytokines in OA and the lack of translational results to date. Our findings also highlight the potential clinical benefits of accurately phenotyping KOA patients, including improved patient stratification, tailored therapies, and the discovery of novel treatments.

Biological and glucocorticoids treatment impair the medium-term immunogenicity to SARS-CoV-2 mRNA vaccines in autoimmune inflammatory rheumatic diseases

BACKGROUND

This study aims to assess the sustained immunological response to the SARS-CoV-2 vaccine in patients with autoimmune inflammatory rheumatic diseases (AIRD) undergoing different treatment regimens.

METHODS

We conducted a prospective observational study involving 157 AIRD patients without prior COVID-19 infection. Treatment regimens included non-treatment or glucocorticoid-only (not-treated/GCs), non-biological drugs, biological therapy, and JAK inhibitors. All participants completed the two-dose vaccine schedule, and 110 of them received an additional booster dose. Serum samples were collected approximately 3-6 months after the second and third vaccine doses to measure antibodies against the Spike protein (antiS-AB) and neutralizing antibodies (nAB) targeting six SARS-CoV-2 variants.

RESULTS

Following the third dose, all patients exhibited a significant increase in antiS-AB (FC = 15, p < 0.0001). Patients under biological therapy had lower titres compared to the non-biological (66% decrease, p = 0.038) and the not-treated/GCs group (62% decrease, p = 0.0132), with the latter persisting after the booster dose (86% decrease, p = 0.0027). GC use was associated with lower antiS-AB levels in the biological group (87% decrease, p = 0.0124), although not statistically significant after confounders adjustment. nABs showed the highest positivity rates for the wild-type strain before (50%) and after the booster dose (93%), while the Omicron variant exhibited the lowest rates (11% and 55%, respectively). All variants demonstrated similar positivity patterns and good concordance with antiS-AB (AUCs from 0.896 to 0.997).

CONCLUSIONS

The SARS-CoV-2 vaccine booster strategy effectively elicited a sustained antibody immune response in AIRD patients. However, patients under biological therapies exhibited a reduced response to the booster dose, particularly when combined with GCs.

Metabolic and inflammatory profiles define phenotypes with clinical relevance in female knee osteoarthritis patients with joint effusion

OBJECTIVES

Osteoarthritis has been the subject of abundant research in the last years with limited translation to the clinical practice, probably due to the disease's high heterogeneity. In this study, we aimed to identify different phenotypes in knee osteoarthritis (KOA) patients with joint effusion based on their metabolic and inflammatory profiles.

METHODS

A non-supervised strategy based on statistical and machine learning methods was applied to 45 parameters measured on 168 female KOA patients with persistent joint effusion, consecutively recruited at our hospital after a monographic OA outpatient visit. Data comprised anthropometric and metabolic factors and a panel of systemic and local inflammatory markers. The resulting clusters were compared regarding their clinical, radiographic and ultrasound severity at baseline and their radiographic progression at two years.

RESULTS

Our analyses identified four KOA inflammatory phenotypes (KOIP): a group characterized by metabolic syndrome, probably driven by body fat and obesity, and by high local and systemic inflammation (KOIP-1); a metabolically healthy phenotype with mild overall inflammation (KOIP-2); a non-metabolic phenotype with high inflammation levels (KOIP-3); and a metabolic phenotype with low inflammation and cardiovascular risk factors not associated with obesity (KOIP-4). Of interest, these groups exhibited differences regarding pain, functional disability and radiographic progression, pointing to a clinical relevance of the uncovered phenotypes.

CONCLUSION

Our results support the existence of different KOA phenotypes with clinical relevance and differing pathways regarding their pathophysiology and disease evolution, which entails implications in patients' stratification, treatment tailoring and the search of novel and personalized therapies.

Social Media Use Among Members of the Assessment of Spondyloarthritis International Society: Results of a Web-Based Survey

BACKGROUND

The use of social media in health care may serve as a beneficial tool for education, information dissemination, telemedicine, research, networking, and communications. To better leverage the benefits of social media, it is imperative to understand the patterns of its use and potential barriers to its implementation in health care. A previous study in 2016 that investigated social media use among young clinical rheumatologists (≤45 years) and basic scientists showed that there was substantial social media use among them for social and professional reasons. However, there is a limited inquiry into social media use in different areas of rheumatology, such as spondyloarthritis.

OBJECTIVE

We aimed to explore the motivations, barriers, and patterns of social media use among an international group of experts in spondyloarthritis.

METHODS

We distributed a web-based survey via email from March 2021 to June 2021 to 198 members of the Assessment of Spondyloarthritis International Society. It contained 24 questions about demographic characteristics, patterns of current social media use, and perceptions of utility. Univariable and multivariable logistic regression analyses were performed to identify the characteristics associated with use trends.

RESULTS

The response rate was 78.8% (156/198). Of these, 93.6% (146/156) of participants used at least one social media platform. Apart from internet-based shopping and entertainment, the use of social media for clinical updates (odds ratio [OR] 6.25, 95% CI 2.43-16.03) and research updates (OR 3.45, 95% CI 1.35-8.78) were associated with higher social media consumption. Among the respondents, 66% (103/156) used social media in a work-related manner. The use of social media for new web-based resources (OR 6.55, 95% CI 2.01-21.37), interaction with international colleagues (OR 4.66, 95% CI 1.21-17.90), and establishing a web-based presence (OR 4.05, 95% CI 1.25-13.13) were associated with higher levels of consumption for work-related purposes. Time investment, confidentiality concerns, and security concerns were the top 3 challenges to a wider adoption of social media.

CONCLUSIONS

Most respondents (103/156, 66%) use social media in a work-related manner. Professional development, establishing a web-based presence, and international collaboration were associated with higher use. Challenges to social media adoption should be addressed to maximize its benefits.

Association between HLA-B27 and peripheral spondyloarthritis phenotype: results from the ASAS perSpA study

OBJECTIVE

To analyse the influence of HLA-B27 in the phenotypical expression of peripheral spondyloarthritis (pSpA).

METHOD

This is an observational cross-sectional study using data from the Assessment of SpondyloArthritis international Society perSpA registry, including all patients with an available HLA-B27 test result and with a diagnosis of pSpA or psoriatic arthritis (PsA) as per rheumatologist's judgement. Demographic and clinical data, presence of extra musculoskeletal manifestations (EMM) and fibromyalgia were the variables included in a simple and multiple logistic regression model to assess their association to HLA-B27 positivity.

RESULTS

From the 4465 patients included in the registry, 790 were classified as having either pSpA or PsA and had the HLA-B27 typing available. HLA-B27-positive patients presented a male predominance, had an earlier disease onset and a shorter diagnostic delay compared with the negatives. HLA-B27-positive patients presented a higher frequency of axial involvement, radiographic sacroiliitis, enthesitis and uveitis. Also, root joint involvement, poliarticular joint patern and tarsitis were significantly higher within HLA-B27-positive patients. Furthermore, we did not observe any association between the presence of HLA-B27 and peripheral joint damage, dactylitis, other EMM (psoriasis, inflammatory bowel disease) or fibromyalgia.The multivariable analysis confirmed the independent association of HLA-B27 positivity with male sex, an earlier onset of the disease, the presence of axial involvement, tarsitis and uveitis.

SUMMARY

In summary, the presence of HLA-B27 in pSpA patients was associated with earlier disease onset and higher axial involvement, tarsitis and uveitis, but not with other EMM, fibromyalgia or peripheral structural damage.

Uveitis in peripheral spondyloarthritis patients: an ancillary analysis of the ASAS-PerSpA study

Background:

Acute anterior uveitis (AAU) is the most frequent extra-musculoskeletal manifestation in spondyloarhtritis (SpA). Previous data on AAU focused on axial disease; therefore, it is not well known whether the clinical characteristics of patients with AAU and recurrent AAU differ between patients with axial and peripheral SpA.

Objective:

Primary objective was to compare the clinical characteristics of patients with AAU from patients without AAU in axial and peripheral spondyloarthritis (SpA) patients. Secondary objectives were to describe the clinical features of patients with AAU in the subset of patients with peripheral SpA (pSpA) and the clinical characteristics of patients with recurrent AAU in SpA patients.

Design:

This is an ancillary analysis of the ASAS-PerSpA study which included 3152 patients, 2719 patients with axSpA and 433 with pSpA according to rheumatologist judgement.

Methods:

Recurrent AAU was defined as the presence of two or more episodes of AAU ever. Univariable and multivariable binary logistic regression analyses were conducted to identify factors associated with the presence of AAU ever and the presence of recurrent AAU.

Results:

Overall, 663 patients (21%) presented AAU. Of them, 444 (66.9%) presented recurrent episodes. In patients with SpA, HLA-B27 positivity is the most important factor linked to the presence of AAU, odds ratio (OR) = 2.70 (95% CI = 2.04–3.6). In patients with pSpA, HLA-B27 positivity was also the most relevant factor linked to the presence of AAU, OR = 6.08 (95% CI = 2.72–15.68). Moreover, disease duration, younger age and higher body mass index (BMI) were the only factors slightly linked to the presence of recurrent episodes, OR = 1.03 (95% CI = 1.01–1.04), OR = 1.01 (95% CI = 1.00–1.03) and OR = 1.04 (95% CI = 1.01–1.08), respectively.

Conclusion:

HLA-B27 positivity is the most relevant factor linked to AAU risk in SpA patients, and this association is even stronger in those patients with pSpA. Moreover, our study did not find an association between HLA-B27 positivity and recurrent AAU in SpA patients.

Sustained low disease activity measured by ASDAS slow radiographic spinal progression in axial spondyloarthritis patients treated with TNF-inhibitors: data from REGISPONSERBIO

Background

To evaluate the influence of the disease activity on radiographic progression in axial spondyloarthritis (axSpA) patients treated with TNF inhibitors (TNFi).

Methods

The study included 101 axSpA patients from the Spanish Register of Biological Therapy in Spondyloarthritides (REGISPONSERBIO), which had clinical data and radiographic assessment available. Patients were classified into 2 groups based on the duration of TNFi treatment at baseline: (i) long-term treatment (≥4 years) and (ii) no long-term treatment (< 4 years). Radiographs were scored by two readers according to the modified Stoke Ankylosing Spondylitis Spine Score (mSASSS) with known chronology. Disease activity differences between patients’ groups at each time point were assessed using a linear mixed-effect model.

Results

Radiographic progression was defined as an increase in ≥2 mSASSS units. At inclusion, approximately half of the patients (45.5%) were receiving long-term treatment with TNFi (≥4 years). In this group of subjects, a significant difference in averaged Ankylosing Spondylitis disease Activity Score (ASDAS) across follow-up was found between progressors and non-progressors (2.33 vs 1.76, p=0.027, respectively). In patients not under long-term TNFi treatment (54.5%) though, no significant ASDAS differences were observed between progressors and non-progressors until the third year of follow-up. Furthermore, no significant differences were found in progression status, when disease activity was measured by Bath Ankylosing spondylitis Disease Activity Index (BASDAI) and C reactive protein (CRP).

Conclusions

Patients on long-term TNFi treatment with a mean sustained low disease activity measures by ASDAS presented lower radiographic progression than those with active disease.

Assessment of radiographic sacroiliitis in anteroposterior lumbar vs conventional pelvic radiographs in axial spondyloarthritis

OBJECTIVE

The aim was to investigate the reliability and validity of radiographic sacroiliitis assessment in anteroposterior (AP) lumbar radiographs compared with conventional pelvic radiographs in patients with axial spondyloarthritis (axSpA).

METHODS

Patients from the German Spondyloarthritis Inception Cohort were selected based on the availability of pelvic and AP lumbar radiographs with visible SI joints at baseline and year 2. Two readers scored the images independently in a random order according to the modified New York criteria. The sacroiliitis sum score was calculated as the mean of both readers. Patients were classified as radiographic (r-)axSpA if radiographic sacroiliitis of grade ≥2 bilaterally or grade ≥3 unilaterally was present in the opinion of both readers and as non-radiographic (nr-)axSpA otherwise. The reliability and validity of sacroiliitis assessment in AP lumbar radiographs was assessed using intraclass correlation coefficients (ICCs), absolute agreement and κ statistics.

RESULTS

A total of 226 sets of radiographs were scored from 113 patients included in the study. The ICC for the sacroiliitis sum score was 0.91 at both baseline and year 2. A total of 62 (54.9%) and 55 (48.7%) patients were classified as r-axSpA at baseline and 65 (57.5%) and 60 (53.1%) patients at year 2 based on evaluation of pelvic and AP lumbar radiographs, respectively. The absolute agreement between the methods on the classification was 84.9 and 85.0% at baseline and year 2, respectively, with the κ of 0.70 at both time points.

CONCLUSION

Radiographic sacroiliitis can be assessed in AP lumbar radiographs with a similar reliability to conventional pelvic radiographs.

Clinical and imaging characteristics of osteitis condensans ilii as compared with axial spondyloarthritis

OBJECTIVES

Osteitis condensans ilii (OCI) has become an important differential diagnosis for axial spondyloarthritis (axSpA). The objective of this matched case-control study was to investigate demographic, clinical, laboratory and MRI characteristics of OCI as compared with axial spondyloarthritis (axSpA).

METHODS

A total of 60 patients diagnosed with OCI were included in the final analysis. From 27 of these patients, MRIs of the sacroiliac joints were available. OCI patients were matched with a 1:1 ratio by back pain duration to patients with definite axSpA in order to compare clinical, laboratory and MRI characteristics.

RESULTS

The OCI patients were nearly all females (96.7 vs 46.7%), had a significantly lower prevalence of inflammatory back pain (39.5 vs 88.9%), a significantly lower percentage of HLA-B27 positives (35.2 vs 80.0%) and a lower prevalence of the majority of other SpA features as compared with axSpA patients. Interestingly, there was no difference in the prevalence of osteitis in the sacroiliac joints (92.6 vs 85.2% in OCI and axSpA, respectively, P = 0.44), but there was a difference in the prevalence of erosions (7.4 vs 66.7%, respectively, P = 0.0001). In addition, in OCI nearly all lesions were localized in the anterior part of the sacroiliac joints while in axSpA lesions were localized predominantly in the middle part of the joint (for osteitis: 96 vs 4% in OCI and 28.6 vs 71.4% in axSpA; P = 0.0002 for the inter-group difference).

CONCLUSION

Clinical and imaging features of OCI compared with axSpA are described that should help in differential diagnosis.

CD4 and CD8 Lymphocyte Counts as Surrogate Early Markers for Progression in SARS-CoV-2 Pneumonia: A Prospective Study

BACKGROUND

COVID-19 pathophysiology and the predictive factors involved are not fully understood, but lymphocytes dysregulation appears to play a role. This paper aims to evaluate lymphocyte subsets in the pathophysiology of COVID-19 and as predictive factors for severe disease.

PATIENT AND METHODS

A prospective cohort study of patients with SARS-CoV-2 bilateral pneumonia recruited at hospital admission. Demographics, medical history, and data regarding SARS-CoV-2 infection were recorded. Patients systematically underwent complete laboratory tests, including parameters related to COVID-19 as well as lymphocyte subsets study at the time of admission. Severe disease criteria were established at admission, and patients were classified on remote follow-up according to disease evolution. Linear regression models were used to assess associations with disease evolution, and Receiver Operating Characteristic (ROC) and the corresponding Area Under the Curve (AUC) were used to evaluate predictive values.

RESULTS

Patients with critical COVID-19 showed a decrease in CD3+CD4+ T cells count compared to non-critical (278 (485 IQR) vs. 545 (322 IQR)), a decrease in median CD4+/CD8+ ratio (1.7, (1.7 IQR) vs. 3.1 (2.4 IQR)), and a decrease in median CD4+MFI (21,820 (4491 IQR) vs. 26,259 (3256 IQR)), which persisted after adjustment. CD3+CD8+ T cells count had a high correlation with time to hospital discharge (PC = -0.700 (-0.931, -0.066)). ROC curves for predictive value showed lymphocyte subsets achieving the best performances, specifically CD3+CD4+ T cells (AUC = 0.756), CD4+/CD8+ ratio (AUC = 0.767), and CD4+MFI (AUC = 0.848).

CONCLUSIONS

A predictive value and treatment considerations for lymphocyte subsets are suggested, especially for CD3CD4+ T cells. Lymphocyte subsets determination at hospital admission is recommended.

Incorporation of the anteroposterior lumbar radiographs in the modified Stoke Ankylosing Spondylitis Spine Score improves detection of radiographic spinal progression in axial spondyloarthritis

Background

To evaluate the performance of the extended modified Stoke Ankylosing Spondylitis Spine Score (mSASSS) incorporating information from anteroposterior (AP) lumbar radiographs as compared to the conventional mSASSS in detection of radiographic spinal progression in patients with axial spondyloarthritis (axSpA)

Methods

A total of 210 patients with axSpA, 115 with radiographic axSpA (r-axSpA), and 95 with non-radiographic axSpA (nr-axSpA), from the GErman SPondyloarthritis Inception Cohort (GESPIC), were included in the analysis based on the availability of spinal radiographs (cervical spine lateral, lumbar spine lateral, and AP views), at baseline and year 2. Two trained readers independently scored lateral cervical and lumbar spine images according to the mSASSS system (0–3 per vertebral corner, 0–72 in total). In addition, all vertebral corners of vertebral bodies visible on lumbar AP radiographs (lower T12 to upper S1) were assessed according to the same scoring system that resulted in a total range for the extended mSASSS from 0 to 144. Reliability and sensitivity to detect radiographic spinal progression of the extended mSASSS as compared to the conventional mSASSS were evaluated.

Results

The reliability of conventional and extended scores was excellent with intraclass correlation coefficients (ICCs) of 0.926 and 0.927 at baseline and 0.920 and 0.933 at year 2, respectively. The mean ± SD score for mSASSS and extended mSASSS at baseline were 4.25 ± 8.32 and 8.59 ± 17.96, respectively. The change score between baseline and year 2 was 0.73 ± 2.34 and 1.19 ± 3.73 for mSASSS and extended mSASSS, respectively. With the extended mSASSS, new syndesmophytes after 2 years were detected in 4 additional patients, new syndesmophytes or growth of existing syndesmophytes in 5 additional patients, and progression by ≥ 2 points in the total score in 14 additional patients meaning a 25%, 28%, and 46% increase in the proportion of patients with progression according to the respective definition as compared to the conventional score.

Conclusions

Incorporation of lumbar AP radiographs in the assessment of structural damage in the spine resulted into detection of additional patients with radiographic spinal progression not captured by the conventional mSASSS score.

Withdrawal of infliximab therapy in ankylosing spondylitis in persistent clinical remission, results from the REMINEA study

Background

Recent data suggest that anti-TNF doses can be reduced in ankylosing spondylitis (AS) patients. Some authors even propose withdrawing treatment in patients in clinical remission; however, at present there is no evidence to support this.

Objective

To assess how long AS patients with persistent clinical remission remained free of flares after anti-TNF withdrawal and to evaluate the effects of treatment reintroduction. We also analyze the characteristics of patients who did not present clinical relapse.

Methods

Multicenter, prospective, observational study of a cohort of patients with active AS who had received infliximab as a first anti-TNF treatment and who presented persistent remission (more than 6 months). We recorded at baseline and every 6–8 weeks over the 12-month period the age, gender, disease duration, peripheral arthritis or enthesitis, HLA-B27 status, BASDAI, CRP, ESR, BASFI, and three visual analogue scales, spine global pain, spinal night time pain, and patient’s global assessment.

Results

Thirty-six out of 107 patients (34%) presented persistent remission and were included in our study. After treatment withdrawal, 21 of these 36 patients (58%) presented clinical relapse during follow-up. Infliximab therapy was reintroduced and only 52% achieved clinical remission, as they had before the discontinuation of infliximab; in an additional 10%, reintroduction of infliximab was ineffective, obliging us to change the anti-TNF therapy. No clinical or biological factors were associated with the occurrence of relapse during the follow-up.

Conclusions

Two thirds of patients in clinical remission presented clinical relapse shortly after infliximab withdrawal. Although the reintroduction of infliximab treatment was safe, half of the patients did not present the same clinical response that they had achieved prior to treatment withdrawal.

Increased prevalence of asymptomatic vertebral fractures in HIV-infected patients over 50 years of age

The prevalence of asymptomatic vertebral fracture in HIV-infected patients over 50 was 20%, associated with older age, male sex, longer time since HIV diagnosis, and tubular renal alterations. Vertebral fractures were independent of osteoporosis at lumbar spine, and were not predicted by the use of the FRAX equation.

PURPOSE

Vertebral fractures (VF) are the hallmark of osteoporotic fractures. Our objective was to determine the prevalence of asymptomatic VF and associated factors in HIV-infected patients over 50 years, and the role of FRAX equation.

METHODS

In a cross-sectional study, a diagnosis of VF was established by the semiquantitative method of Genant in thoracic and lumbar radiographs. Simultaneously, a dual X-ray absorptiometry (DXA), bone and kidney-related analytical, calcium intake, physical exercise, HIV-related factors, and FRAX estimation were evaluated.

RESULTS

Overall, 128 patients (35 women, 27%) were included. Mean age was 57 years. Hypophosphatemia and tubular renal dysfunction were observed in 13 and 21%. DXA scan showed osteopenia and osteoporosis at hip in 65 and 7% of patients, and in spine in 39 and 34%, respectively. VF were observed in 26 patients (20%), with a trend to be associated with lower serum phosphate, increased alkaline phosphatase, and with lower daily calcium intake. In a multivariate analysis, older age (OR 1.2 per year; 14% of VF at 50-55; 44% at 65-70), male sex (26 vs 6%), longer time since HIV diagnosis, and renal and tubular dysfunction were the associated factors. VF were not related with osteoporosis at lumbar spine, and could not be predicted by the FRAX equation.

CONCLUSIONS

The prevalence of asymptomatic vertebral fractures is high in HIV-infected patients older than 50 years, and is not identified by the presence of osteoporosis in spine neither predicted by the FRAX equation. Spine and lumbar X-rays should be routinely performed in this aging population.

Hematopoietic and mesenchymal stem cells: a promising new therapy for spondyloarthritis?

In the last years, a considerable progress has been made in the treatment of spondyloarthritides. Nonetheless, there remain a considerable number of patients who are unresponsive to all current therapies. Since the late 1990s, numerous trials have investigated the use of stem cell transplantation as a new approach for the treatment of autoimmune disease, particularly with hematopoietic stem cell transplantation. More recently, the research has focused on mesenchymal stem cell application due to their low immunogenicity and immunomodulatory properties. In this article, we summarize available data on hematopoietic stem cell and mesenchymal stem cell use for the treatment of spondyloarthritides and discuss the data gaps and possible research agenda in this area.

Chemical modification of jute fibers for the production of green-composites

Natural fiber reinforced composites is an emerging area in polymer science. Fibers derived from annual plants are considered a potential substitute for non-renewable synthetic fibers like glass and carbon fibers. The hydrophilic nature of natural fibers affects negatively its adhesion to hydrophobic polymeric matrices. To improve the compatibility between both components a surface modification has been proposed. The aim of the study is the chemical modification of jute fibers using a fatty acid derivate (oleoyl chloride) to confer hydrophobicity and resistance to biofibers. This reaction was applied in swelling and non-swelling solvents, pyridine and dichloromethane, respectively. The formation of ester groups, resulting from the reaction of oleoyl chloride with hydroxyl group of cellulose were studied by elemental analysis (EA) and Fourier Transform infrared spectroscopy (FTIR). The characterization methods applied has proved the chemical interaction between the cellulosic material and the coupling agent. The extent of the reactions evaluated by elemental analysis was calculated using two ratios. Finally electron microscopy was applied to evaluate the surface changes of cellulose fibers after modification process.