Frailty and risk of osteoporotic fractures in patients with rheumatoid arthritis: Data from the Ontario Best Practices Research Initiative

Frailty Screening is Associated with Hospitalization and Decline in Quality of Life and Functional Status in Older Patients with Inflammatory Bowel Disease

BACKGROUND AND AIMS

Our goals were to study frailty screening in association with hospitalization and decline in quality of life [QoL] and functional status in older patients with inflammatory bowel diseases [IBD].

METHODS

This was a prospective multicentre cohort study in IBD patients ≥65 years old using frailty screening [G8 Questionnaire]. Outcomes were all-cause, acute, and IBD-related hospitalization, any infection, any malignancy, QoL [EQ5D-3L], and functional decline (Instrumental Activities of Daily Living [IADL]) during 18 months of follow-up. Confounders were age, IBD type, biochemical disease activity [C-reactive protein ≥10 mg/L and/or faecal calprotectin ≥250 µg/g], and comorbidity [Charlson Comorbidity Index].

RESULTS

Of 405 patients, with a median age of 70 years, 196 [48%] were screened as being at risk for frailty. All-cause hospitalizations occurred 136 times in 96 patients [23.7%], and acute hospitalizations 103 times in 74 patients [18.3%]. Risk of frailty was not associated with all-cause (adjusted hazard ratio [aHR] 1.5, 95% confidence interval [CI] 0.9-2.4), but was associated with acute hospitalizations [aHR 2.2, 95% CI 1.3-3.8]. Infections occurred in 86 patients [21.2%] and these were not associated with frailty. A decline in QoL was experienced by 108 [30.6%] patients, and a decline in functional status by 46 patients [13.3%]. Frailty screening was associated with a decline in QoL (adjusted odds ratio [aOR] 2.1, 95% CI 1.3-3.6) and functional status [aOR 3.7, 95% CI 1.7-8.1].

CONCLUSIONS

Frailty screening is associated with worse health outcomes in older patients with IBD. Further studies are needed to assess the feasibility and effectiveness of its implementation in routine care.

Psychometric Properties of Frailty Instruments in Adults With Rheumatoid Arthritis: A Systematic Review

OBJECTIVE

Examine psychometric properties of frailty instruments used in adults with rheumatoid arthritis (RA) to inform selection of frailty instruments for clinical and research use.

METHODS

A systematic review was registered in PROSPERO. Studies measuring frailty in adults with RA published before May 25, 2022, were searched in six electronic databases. Level of evidence of psychometric properties were synthesized and graded for each frailty instrument using Consensus-Based Standards for the Selection of Health Measurement Instruments methodology.

RESULTS

There were 22 articles included in the review, and psychometric properties of 16 frailty instruments were examined. RA cohorts were predominantly female with moderate RA disease activity, mean age was 60.1 years, and frailty prevalence ranged widely from 10% to 85%. Construct validity was the only psychometric property routinely examined for frailty instruments in RA, and nearly all (14/16) performed favorably in this domain. Frailty correlated most frequently with older age, higher RA disease activity, and worse physical function. Internal consistency, measurement error, and content validity were examined infrequently. Reliability and responsiveness data were not reported. Six frailty instruments were rated highest in adults with RA: three adaptations of Fried's Criteria, 32-Item and 45-Item Frailty Indexes, and the Comprehensive Rheumatologic Assessment of Frailty.

CONCLUSION

Six frailty instruments possessed the highest-rated psychometric properties in RA. These instruments demonstrated construct validity of frailty with important outcomes in RA. Frailty assessment shows promise to inform risk stratification in RA, but studies are needed to evaluate reliability, responsiveness, and validity to support accuracy of frailty measurement in adults with RA who may have disease-related features that differentially impact outcomes.

Risk Factors and Clinical Outcomes Associated With Sarcopenia in Rheumatoid Arthritis: A Systematic Review and Meta-analysis

ABSTRACT

Sarcopenia is underrecognized in patients with rheumatoid arthritis (RA). Risk factors of sarcopenia and its impact on outcomes in RA patients are relatively unknown. We conducted a systematic review to identify factors and outcomes associated with sarcopenia in RA. We conducted this review according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) 2020 guidelines. We searched PubMed, Embase, CINAHL, and Web of Science databases by combining the following search concepts: (1) RA and (2) sarcopenia. Articles were included if they included RA patients, assessed for sarcopenia using a consensus working group definition, and assessed for clinical outcomes. Meta-analysis was performed using studies that shared the same sarcopenia definition and consistency in reporting patient or disease variables. Our search identified 3602 articles. After removal of duplicates, title and abstract screen, and full-text review, 16 articles were included for final analysis. All studies had observational study designs. The pooled prevalence of sarcopenia ranged from 24% to 30%, depending on the criteria for sarcopenia used. Factors associated with sarcopenia included higher 28-joint Disease Activity Scale scores (+0.39; 95% confidence interval, +0.02 to +0.77) and baseline methotrexate use (odds ratio, 0.70; 95% confidence interval, 0.51-0.97). Baseline glucocorticoid use had a positive correlation with sarcopenia in multiple studies. Several studies found lower bone mineral density and higher incidence of falls and fractures in patients with sarcopenia. Sarcopenia is prevalent in RA, and it may be associated with higher RA disease activity, lower bone mineral density, and increased falls and fractures. Therefore, early screening of sarcopenia in RA patients is important to incorporate into clinical rheumatology practice.

SLICC-Frailty Index and Its Association with Low Bone Mineral Density and Vertebral Fractures in Women with Systemic Lupus Erythematosus

The Systemic Lupus International Clinics (SLICC)-Frailty Index (FI) is associated with adverse outcomes in systemic lupus erythematosus (SLE). However, to our knowledge, its association with bone mineral density (BMD) and vertebral fractures (VF), has not been investigated using a standardized methods. Our aim was to evaluate the relationship between frailty assessed by SLICC-FI, and BMD and VF in Mestizo women with SLE. Adult women were included in this cross-sectional study. Information concerning the risk factors for VF and BMD in the lumbar spine and total hip was acquired. SLICC-FI was assessed at baseline. A semi-quantitative method was utilized to evaluate the prevalence of VF on lateral thoracolumbar radiographs. Univariate and multivariate regression analyses were performed adjusting for age, body mass index (BMI), SLE duration, cumulative glucocorticoid dose, bisphosphonate use, and BMD measurements. We included 202 women with SLE (mean age [SD] = 43.3 [13.6] years). The mean (SD) SLICC-FI value was 0.14 (0.09). Eleven (5.4%) patients were categorized as robust, 62 (30.7%) as relatively less fit, 84 (41.6%) as least fit, and 45 (22.3%) as frail. Both univariate and multivariate models showed associations between frailty (defined as SLICC-FI > 0.21) and prevalent VF in the entire population (OR 5.76, 95% CI 2.53-13.12; P < 0.001) and in the premenopausal group (OR 4.29, 95% CI; P = 0.047). We also found an association between the SLICC-FI and low BMD. In conclusion, frailty assessed by SLICC-FI might be associated with VF and low BMD in mestizo females with SLE.

Frailty in people with rheumatoid arthritis: a systematic review of observational studies

Background: Frailty, an age-related decline in physiological reserve, is an increasingly important concept in the management of chronic diseases. The implications of frailty in people with rheumatoid arthritis are not well understood. We undertook a systematic review to assess prevalence of frailty in people with rheumatoid arthritis, and the relationship between frailty and disease activity or clinical outcomes. Methods: We searched four electronic databases (January 2001 to April 2021) for observational studies assessing the prevalence of frailty (any frailty measure) in adults (≥18 years) with rheumatoid arthritis, or analysing the relationship between frailty and disease activity or clinical outcomes (e.g. quality of life, hospitalisation or mortality) in people with rheumatoid arthritis. Study quality was assessed using an adapted Newcastle-Ottawa Scale. Screening, quality assessment and data extraction were performed independently by two reviewers. We used narrative synthesis. Results: We identified 17 analyses, from 14 different populations. 15/17 were cross-sectional. Studies used 11 different measures of frailty. Frailty prevalence ranged from 10% (frailty phenotype) to 36% (comprehensive rheumatologic assessment of frailty) in general adult populations with rheumatoid arthritis. In younger populations (<60 or <65 years) prevalence ranged from 2.4% (frailty phenotype) to 19.9% (Kihon checklist) while in older populations (>60 or >65) prevalence ranged from 31.2% (Kihon checklist) to 55% (Geriatric 8 tool). Frailty was cross-sectionally associated with higher disease activity (10/10 studies), lower physical function (7/7 studies) and longer disease duration (2/5 studies), and with hospitalization and osteoporotic fractures (1/1 study, 3.7 years follow-up). Conclusion: Frailty is common in rheumatoid arthritis, including those aged <65 years, and is associated with a range of adverse features. However, these is heterogeneity in how frailty is measured. We found few longitudinal studies making the impact of frailty on clinical outcomes over time and the extent to which frailty is caused by rheumatoid arthritis unclear.

Osteoporosis and fractures in rheumatoid arthritis - risk factors

In this chapter, we emphasize among rheumatoid arthritis (RA) patients, whom and how to screen for osteoporosis. We highlight certain modalities, advancements in technology, secondary osteoporosis workup, and laboratory testing as well as their caveats. Finally, we discuss current guidance on how to direct the laboratory and radiology testing in the context of the individual patient with RA to guide and select from the osteoporosis treatment options currently available.

Risk factors for osteoporosis and fractures in rheumatoid arthritis

People with rheumatoid arthritis (RA) have both disease-specific risk factors for osteoporosis and fractures in addition to those that affect the general population. Disease specific risks include directly pathogenic auto-antibodies, chronic exposure to systemic inflammation, and joint damage causing early disability. Risk factors that affect the general population which may have a higher prevalence in RA include smoking, calcium and vitamin D deficiency as well as hypogonadism. Additionally, chronic exposure to glucocorticoids results in reduced bone mineral density and body composition changes which can further increase fracture risk. In this review we discuss these risk-factors for osteoporosis as well as factors that may impact fall and fracture risk in people with RA.

The Bioimpedance Phase Angle may be Associated With Frailty in Rheumatoid Arthritis Patients: Results From a Prospective, Cohort Study

OBJECTIVES

This study investigated whether the phase angle (PhA) on bioelectrical impedance analysis (BIA) is related to frailty in rheumatoid arthritis (RA) patients.

METHODS

Data from a prospective cohort study of RA patients were analyzed. The PhA was assessed by the BIA method, and frailty was assessed by the Kihon Check List (KCL) annually. The cutoff value of the PhA for frailty was calculated by receiver-operating characteristic analysis. The relationships between the PhA and frailty were evaluated by logistic regression analysis. The relationships between the change in PhA and frailty status and the KCL score were evaluated by analysis of covariance and multiple regression analysis.

RESULTS

A total of 170 patients (81.2% female, 66.2±13.1 years) were included in the analysis. A PhA of less than the cutoff for frailty was significantly associated with frailty (odds ratio: 4.75, 95% confidence interval: 1.86-12.17). Change in the PhA was significantly associated with change in the KCL score (β = -0.15). In robust patients, there was a significant difference in the rate of change of the PhA between the group that became pre-frail in the next year and the group that remained robust.

CONCLUSIONS

The PhA may be associated with frailty in RA patients.

Frailty in rheumatoidrmdopen-2021-002111 arthritis and its relationship with disease activity, hospitalisation and mortality: a longitudinal analysis of the Scottish Early Rheumatoid Arthritis cohort and UK Biobank

OBJECTIVE

To assess the prevalence of frailty in rheumatoid arthritis (RA) and its association with baseline and longitudinal disease activity, all-cause mortality and hospitalisation.

PARTICIPANTS

People with RA identified from the Scottish Early Rheumatoid Arthritis (SERA) inception cohort (newly diagnosed, mean age 58.2 years) and UK Biobank (established disease identified using diagnostic codes, mean age 59 years). Frailty was quantified using the frailty index (both datasets) and frailty phenotype (UK Biobank only). Disease activity was assessed using Disease Activity Score in 28 joints (DAS28) in SERA. Associations between baseline frailty and all-cause mortality and hospitalisation was estimated after adjusting for age, sex, socioeconomic status, smoking and alcohol, plus DAS28 in SERA.

RESULTS

Based on the frailty index, frailty was common in SERA (12% moderate, 0.2% severe) and UK Biobank (20% moderate, 3% severe). In UK Biobank, 23% were frail using frailty phenotype. Frailty index was associated with DAS28 in SERA, as well as age and female sex in both cohorts. In SERA, as DAS28 lessened over time with treatment, mean frailty index also decreased. The frailty index was associated with all-cause mortality (HR moderate/severe frailty vs robust 4.14 (95% CI 1.49 to 11.51) SERA, 1.68 (95% CI 1.26 to 2.13) UK Biobank) and unscheduled hospitalisation (incidence rate ratio 2.27 (95% CI 1.45 to 3.57) SERA 2.74 (95% CI 2.29 to 3.29) UK Biobank). In UK Biobank, frailty phenotype also associated with mortality and hospitalisation.

CONCLUSION

Frailty is common in early and established RA and associated with hospitalisation and mortality. Frailty in RA is dynamic and, for some, may be ameliorated through controlling disease activity in early disease.

Clinical Observations of Osteoporosis in Japanese Patients with Rheumatoid Arthritis

Osteoporosis is the one of the major adverse outcomes in patients with rheumatoid arthritis (RA). Recently, we and others have been reported many clinical observations related to osteoporosis in Japanese RA patients. In this article, I reviewed these findings. Japanese patients with RA have a two-fold risk of fractures compared with those without RA. Among the fractures in Japanese RA patients, three quarters of the fractures were non-vertebral fractures. The incidence of non-vertebral fractures did not change, despite an improvement in RA disease activity. Older age, female gender, history of fractures, history of total knee replacements, disease activity scores in 28 joints (DAS28), health assessment questionnaire disability index (HAQ-DI), low bone mineral density, glucocorticoid dose, and vitamin D deficiency were significantly associated with fractures. Older age, high body mass index (BMI), HAQ-DI, and polypharmacy were significantly associated with falls. BMI (both overweight and underweight), DAS28, and HAQ-DI were significantly associated with frailty. Half and three quarters of Japanese men and women with RA had vitamin D deficiency, respectively. The incidence of osteonecrosis of the jaw may be higher in Japanese RA patients than those without RA. Undertreatment of osteoporosis appears to exist in Japanese patients with RA.

Factors associated with frailty in Japanese patients with rheumatoid arthritis: results from the Institute of Rheumatology Rheumatoid Arthritis cohort study

This study aimed to evaluate the prevalence of, and the factors associated with, frailty in Japanese patients with rheumatoid arthritis (RA). Patients with RA enrolled in the Institute of Rheumatology Rheumatoid Arthritis (IORRA) cohort completed self-administered questionnaires, which included the 5-item frailty screening index. Patients were classified as frail, prefrail, or robust based on the 5 components of the frailty screening index. Logistic regression analyses were used to evaluate associations between clinical variables and frailty. Among 3,290 Japanese patients with RA (86.7% female, mean age 62.4 years) who participated this frailty study, 549 (16.7%) patients were categorized as frailty, 2,063 (62.7%) as prefrailty, and 678 (20.6%) as robust. In multivariable models, body mass index (BMI) ≥ 25 kg/m² (odds ratio [OR] 1.87, 95% confidence interval [CI] 1.41 to 2.47), BMI < 18.5 kg/m² (OR 1.31, 95% CI 1.00 to 1.71), disease activity scores in 28 joints (DAS28) (OR 1.32, 95% CI 1.18 to 1.47), Japanese version of Health Assessment Questionnaire disability index (J-HAQ) (OR 1.26, 95% CI 1.04 to 1.52), the European Quality of Life-5 Dimensions (EQ-5D) (OR 0.80, 95% CI 0.74 to 0.85), non-steroidal anti-inflammatory drug (NSAID) use (OR 1.59, 95% CI 1.23 to 1.98), and methotrexate (MTX) use (OR 0.75, 95% CI 0.60 to 0.94) were significantly (P < 0.05) associated with frailty. BMI (both overweight and underweight), DAS28, J-HAQ, EQ-5D, NSAID use, and MTX nonuse appear to be associated with frailty in Japanese patients with RA. Key Points • This is the largest study showing the prevalence and the associated factors of frailty in patients with RA. • Maintaining normal BMI appears to be important for preventing frailty in patients with RA. • We confirmed the significant associations of frailty with high disease activity, high degree of disability, and poor health related QOL in Japanese patients with RA. • NSAID use and MTX nonuse were associated with the frailty in Japanese patients with RA, which could be explained by patients' background.

Frailty in people with rheumatoid arthritis: a systematic review of observational studies

Background: Frailty, an age-related decline in physiological reserve, is an increasingly important concept in the management of chronic diseases. The implications of frailty in people with rheumatoid arthritis are not well understood. We undertook a systematic review to assess the prevalence of frailty in people with rheumatoid arthritis, and the relationship between frailty and clinical outcomes. Methods: We searched three electronic databases (January 2001 to April 2021) for observational studies assessing the prevalence of frailty in adults (≥18 years) with rheumatoid arthritis, or analysing the relationship between frailty and clinical outcomes in the context of rheumatoid arthritis. Titles, abstracts and full texts were assessed independently by two reviewers. Study quality was assessed using an adapted Newcastle-Ottawa Scale. Results: We identified 17 analyses, from 14 different sample populations. 15/17 were cross-sectional. These studies used 11 different measures of frailty. Frailty prevalence ranged from 10% (frailty phenotype) to 36% (comprehensive rheumatologic assessment of frailty) in general adult populations with rheumatoid arthritis. In younger populations (<60 or <65 years) prevalence ranged from 2.4% (frailty phenotype) to 19.9% (Kihon checklist) while in older populations (>60 or >65) prevalence ranged from 31.2% (Kihon checklist) to 55% (Geriatric 8 tool). Frailty was associated with higher disease activity (10/10 studies), lower physical function (7/7 studies), longer disease duration (2/5 studies), hospitalization (1/1 study) and osteoporotic fractures (1/1 study). Conclusion: Our review found that frailty is common in adults with rheumatoid arthritis, including those aged <65 years, and is associated with a range of adverse features. However, these is substantial heterogeneity in how frailty is measured in rheumatoid arthritis. We found a lack of longitudinal studies making the impact of frailty on clinical outcomes over time and the extent to which frailty is caused by rheumatoid arthritis unclear.

Evaluation of a Patient-reported Frailty Tool in Women With Systemic Lupus Erythematosus

OBJECTIVE

Frailty is associated with mortality in systemic lupus erythematosus (SLE), but how best to measure frailty is unclear. We aimed to compare 2 frailty metrics, the self-reported Fatigue, Resistance, Ambulation, Illnesses, and Loss of weight (FRAIL) scale (FS) and the Fried phenotype (FP), in SLE to evaluate differences between frail and nonfrail women and whether frailty is associated with self-reported disability.

METHODS

Adult women aged < 70 years with validated SLE and mild/moderate disease enrolled in this cross-sectional study between August 2018 and October 2019. Correlation and agreement between the FS and the FP were determined. Differences in sociodemographic and disease characteristics, patient-reported outcome measures (PROMs), and biomarkers between frail and nonfrail participants were evaluated, as well as the association of frailty with Valued Life Activities disability.

RESULTS

Of 67 participants, 27% and 18% were frail according to the FS and the FP, respectively. Correlation (r = 0.51; P < 0.0001) and agreement (κ = 0.46; P = 0.0004) between the FS and the FP were significant. Frail women had greater disease damage, high-sensitivity C-reactive protein, and interleukin 6, and worse PROMs according to both frailty definitions. Both frailty measures were associated with self-reported disability after adjustment for age, comorbidity, and disease activity and damage; this relationship was attenuated for the FP.

CONCLUSION

Frailty prevalence was high in this cohort of women with SLE using both frailty definitions, suggesting that frailty may be accelerated in women with SLE, particularly when based exclusively on self-report. Frailty remained associated with self-reported disability in adjusted analyses. The FS may be an informative point-of-care tool to identify frail women with SLE.

Osteoporosis and fractures in rheumatoid arthritis

PURPOSE OF REVIEW

Rheumatoid arthritis (RA) is associated with increased risk for osteoporotic fracture. We highlight RA-specific risk factors for bone mineral density (BMD) loss and fractures and considerations regarding the diagnosis and treatment of osteoporosis in patients with RA.

RECENT FINDINGS

Anticitrullinated protein antibody (ACPA) positivity, although associated with low BMD in early RA, is not associated with accelerated BMD loss over time when compared to ACPA negative individuals. Studies have found reduced BMD in individuals on low doses of glucocorticoids (GCs). Poor functional status and frailty are additional important risk factors for low BMD and fractures. Heightened fracture risk in RA may be mitigated by tight disease control, and biologic therapies are associated with more stable BMD compared to nonbiologic therapies. Evidence-based guidelines specific for treating osteoporosis in patients with RA do not exist. Thus, treatment decisions are based on general osteoporosis guidelines, taking into account additional RA-specific risk factors.

SUMMARY

Recent studies have advanced knowledge of RA-specific risk factors for BMD loss and fractures. Future studies applying these findings to modify established fracture risk algorithms as well as evaluating osteoporosis treatments in RA cohorts are needed to reduce the risk of disabling fractures in these patients.

Beyond Rheumatoid Arthritis Evaluation: What are We Missing?

Rheumatoid Arthritis (RA) is a chronic inflammatory autoimmune systemic disease that preferentially affects small and large joints with a progressive course and can become deforming and disabling. In recent years, much progress has been made in the evaluation of inflammation and disease activity, however, there are other factors that have a high impact on the quality of life of these patients, such as depression, anxiety, fatigue, sleep disorders, suicidal behavior, fibromyalgia, sexual activity, sarcopenia, frailty, cachexia and obesity that are not always evaluated by rheumatologists. This review shows that the evaluation and timely detection of these aspects in patients with RA could interfere with the prognosis and improve their quality of life.

Fracture Risk in Patients with Myasthenia Gravis: A Population-Based Cohort Study

BACKGROUND

Prednisone is a common treatment for myasthenia gravis (MG), and osteoporosis is a known potential risk of chronic prednisone therapy.

OBJECTIVE

Our aim was to evaluate the risk of serious fractures in a population-based cohort of MG patients.

METHODS

An inception cohort of patients with MG was identified from administrative health data in Ontario, Canada between April 1, 2002 and December 31, 2015. For each MG patient, we matched 4 general population comparators based on age, sex, and region of residence. Fractures were identified through emergency department and hospitalization data. Crude overall rates and sex-specific rates of fractures were calculated for the MG and comparator groups, as well as rates of specific fractures. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox regression.

RESULTS

Among 3,823 incident MG patients (followed for a mean of 5 years), 188 (4.9%) experienced a fracture compared with 741 (4.8%) fractures amongst 15,292 matched comparators. Crude fracture rates were not different between the MG cohort and matched comparators (8.71 vs. 7.98 per 1000 patient years), overall and in men and women separately. After controlling for multiple covariates, MG patients had a significantly lower risk of fracture than comparators (HR 0.74, 95% CI 0.63-0.88).

CONCLUSIONS

In this large, population-based cohort of incident MG patients, MG patients were at lower risk of a major fracture than comparators. The reasons for this finding are unclear but may highlight the importance osteoporosis prevention.

Depression, physical function, and disease activity associated with frailty in patients with rheumatoid arthritis

OBJECTIVES

To investigate the clinical and psychosocial backgrounds of frailty in rheumatoid arthritis (RA) patients.

METHODS

Patients with RA between 40 and 79 years of age who visited university hospitals in an urban area were recruited. Well-validated self-reported questionnaires were used to evaluate patient physical function (Health Assessment Questionnaire, HAQ), depressive symptoms (Beck Depression Inventory-II, BDI-II), and frailty (Kihon Checklist). A 28-point Disease Activity Score (DAS-28) was calculated to evaluate RA disease activity.

RESULTS

A total of 375 RA patients, 323 of whom were women, were enrolled (average age: 65.2 ± 9.7 years; average disease duration: 16.6 ± 11.9 years). The prevalence rates of frailty, working-age (40-64 years), young-old (65-74 years), and old-old (≥75 years) patients were 18.5, 28.8, and 36.6%, respectively. Higher age and longer disease duration were associated with frailty. Multivariable logistic regression analysis revealed that HAQ, DAS-28, and BDI-II scores were independently associated with frailty in RA patients.

CONCLUSION

Frailty is common, even among working-age RA patients. Physical function, disease activity, and depressive symptoms were independently associated with frailty. A multidisciplinary intervention approach, along with adequate pharmacological therapy, may promote successful aging in patients with RA.

A Novel Role of Interleukin-6 as a Regulatory Factor of Inflammation-Associated Deterioration in Osteoblast Arrangement

Inflammatory disorders are associated with bone destruction; that is, deterioration in bone cell activities are under the control of the innate immune system. Macrophages play a central role in innate immunity by switching their polarized phenotype. A disturbed immune system causes aberrance in the ordered bone matrix microarrangement, which is a dominant determinant of bone tissue functionalization. However, the precise relationship between the immune system and bone tissue organization is unknown. In this study, the controlled in vitro co-culture assay results showed that M1-polarized macrophages disrupted the osteoblast alignment, which directly modulate the oriented bone matrix organization, by secreting pro-inflammatory cytokines. Notably, interleukin-6 was found to be a key regulator of unidirectional osteoblast alignment. Our results demonstrated that inflammatory diseases triggered bone dysfunction by regulating the molecular interaction between the immune system and bone tissue organization. These findings may contribute to the development of therapeutic targets for inflammatory disorders, including rheumatoid arthritis.

Sex differences in frailty and its association with low bone mineral density in rheumatoid arthritis

Objectives

Frailty in the general population is associated with poor health outcomes including low bone mass and osteoporotic fracture. The relationship between frailty and low bone mineral density (BMD) in rheumatoid arthritis (RA) is unknown. This study examined associations between frailty and BMD in RA, controlling for established osteoporosis risk factors.

Methods

We performed a cross-sectional analysis of a longitudinal RA cohort (n = 138; 117 female, 21 male). Participants fulfilled ACR RA classification criteria. Frailty was evaluated using the Fried Index, categorizing each participant as robust, pre-frail or frail. To identify independent predictors of BMD, we performed a multivariable linear regression analysis. Because risk factors for low BMD differ between sexes, we performed additional sex-stratified multivariable analyses.

Results

Mean age and disease duration were 58.0 ± 10.8 and 19 ± 10.9 years, respectively. The majority of participants were categorized as pre-frail (70%) or frail (10%). Females had higher rates of frailty than males. In the whole cohort, both pre-frail and frail had independent negative associations with BMD (β = −0.074 and −0.092 respectively, p < 0.05). In sex-stratified analyses, frailty did not have a significant association with BMD in females, but had a strong independent negative association in males (β = −0.247, p = 0.001).

Conclusion

Frailty was associated with BMD in patients with RA. Females had higher rates of frailty than males, yet frailty was independently associated with BMD in males but not in females. Frailty appears to be an important factor associated with low BMD; sex may influence this relationship in RA.

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Frailty was independently associated with lower femoral neck BMD in RA participants.

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Frailty was independently associated with lower BMD in males, not females.

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Of the frailty components, weakness had the strongest negative association with BMD.