Inflammation as a Risk of Developing Chronic Kidney Disease in Rheumatoid Arthritis

Kidney damage associated with COVID-19: from the acute to the chronic phase

Severe acute respiratory syndrome coronavirus-2 (SARS-COV-2) infection is well established as a systemic disease including kidney damage. The entry point into the renal cell remains the angiotensin-converting enzyme 2 (ACE-2) receptor and the spectrum of renal lesions is broad, with a clear predominance of structural and functional tubular lesions. The most common form of glomerular injury is collapsing glomerulopathy (CG), which is strongly associated with apolipoprotein L1(APOL-1) risk variants. These acute lesions, which are secondary to the direct or indirect effects of SARS-CoV-2, can progress to chronicity and are specific to long COVID-19 in the absence of any other cause. Residual inflammation associated with SARS-CoV-2 infection, in addition to acute kidney injury (AKI) as a transitional state with or without severe histological lesions, may be responsible for greater kidney function decline in mild-to-moderate COVID-19. This review discusses the evidence for renal histological markers of chronicity in COVID-19 patients and triggers of low-grade inflammation that may explain the decline in kidney function in the post-COVID-19 period.

Rheumatoid arthritis and the risk of chronic kidney diseases: a Mendelian randomization study

Background

The extra-articular lesions of rheumatoid arthritis (RA) are reported to involve multiple organs and systems throughout the body, including the heart, kidneys, liver, and lungs. This study assessed the potential causal relationship between RA and the risk of chronic kidney diseases (CKDs) using the Mendelian randomization (MR) analysis.

Method

Independent genetic instruments related to RA and CKD or CKD subtypes at the genome-wide significant level were chosen from the publicly shared summary-level data of genome-wide association studies (GWAS). Then, we obtained some single-nucleotide polymorphisms (SNPs) as instrumental variables (IVs), which are associated with RA in individuals of European origin, and had genome-wide statistical significance (p5 × 10-8). The inverse-variance weighted (IVW) method was the main analysis method in MR analysis. The other methods, such as weighted median, MR-Egger, simple mode, and weighted mode were used as supplementary sensitivity analyses. Furthermore, the levels of pleiotropy and heterogeneity were assessed using Cochran's Q test and leave-one-out analysis. Furthermore, the relevant datasets were obtained from the Open GWAS database.

Results

Using the IVW method, the main method in MR analysis, the results showed that genetically determined RA was associated with higher risks of CKD [odds ratio (OR): 1.22, 95% confidence interval (CI) 1.13-1.31; p < 0.001], glomerulonephritis (OR: 1.23, 95% CI 1.15-1.31; p < 0.000), amyloidosis (OR = 1.43, 95% CI 1.10-1.88, p < 0.001), and renal failure (OR = 1.18, 95% CI 1.00-1.38, p < 0.001). Then, using multiple MR methods, it was confirmed that the associations persisted in sensitivity analyses, and no pleiotropy was detected.

Conclusion

The findings revealed a causal relationship between RA and CKD, including glomerulonephritis, amyloidosis, and renal failure. Therefore, RA patients should pay more attention to monitoring their kidney function, thus providing the opportunity for earlier intervention and lower the risk of progression to CKDs.

Factors that predict development of chronic kidney disease in patients with rheumatoid arthritis receiving biologic DMARDs and mortality rates

OBJECTIVES

We aimed to determine the choice of biologic/targeted synthetic disease-modifying anti-rheumatic drugs (b/ts-DMARDs), factors associated with the development of chronic kidney disease (CKD), and mortality in RA patients with CKD receiving b/ts-DMARDs.

METHODS

Two thousand one hundred forty-one RA (79.4% female) patients were included in the analysis from the HUR-BIO prospective registry. Patients were divided into the CKD group and the non-CKD group. Age and gender-matched patients were selected from the non-CKD group, and then three main groups were determined. CKD was staged according to the glomerular filtration rate criteria. The clinical characteristics of the patients, disease activities, treatment choices, drug retention rate, and mortality rates were compared between the groups.

RESULTS

CKD was detected in 90/2141 (4.2%) RA patients on b/ts-DMARDs. Forty patients (2.3%) developed CKD during follow-up after the initiation of b/ts-DMARDs. In the CKD group, anti-TNF agents were chosen as the first-line b/ts-DMARDs therapy in 64.4% of patients, with etanercept leading in 31 (34.4%) patients. In multivariate analysis, age at the start of treatment, DAS-28-ESR at last visit, amyloidosis, hypertension, and history of smoking were the factors associated with the development of CKD in RA patients receiving b/ts-DMARDs. The mortality rate in RA-CKD patients until the onset of the pandemic was 15.41 per 1000 patient years, whereas it was 85.9 per 1000 patient years after the pandemic.

CONCLUSION

Comorbidities and control of disease activity are critical in the development of CKD in RA patients receiving b/ts-DMARDs. While there was no significant difference in mortality rate between CKD and non-CKD patients, the overall mortality rate increased after the COVID-19 pandemic duration in both groups.

The Association of Kidney Function and Inflammatory Biomarkers with Epithelial Ovarian Cancer Risk

BACKGROUND

One of the mechanisms of ovarian tumorigenesis is through inflammation. Kidney dysfunction is associated with increased inflammation; thus, we assessed its relationship with ovarian cancer risk.

METHODS

In prospectively collected samples, we evaluated the association of kidney function markers and C-reactive protein (CRP) with ovarian cancer risk in the UK Biobank. We used multivariable-adjusted Cox proportional hazards models to evaluate quartiles of serum and urine markers with ovarian cancer risk overall and by histology. We assessed effect modification by CRP (≤3.0, >3.0 mg/L).

RESULTS

Among 232,908 women (1,110 ovarian cancer cases diagnosed from 2006-2020), we observed no association between estimated glomerular filtration rate and ovarian cancer risk (Q4 vs. Q1: HR, 1.00; 95% confidence intervals, 0.83-1.22). Potassium was associated with endometrioid (Q4 vs. Q1: 0.33, 0.11-0.98) and clear cell (4.74, 1.39-16.16) tumors. Poor kidney function was associated with a nonsignificant increase in ovarian cancer risk among women with CRP>3.0 mg/L (e.g., uric acid Q4 vs. Q1; 1.23, 0.81-1.86), but not CRP≤3.0 mg/L (0.83, 0.66-1.05). Other associations did not vary across CRP categories.

CONCLUSIONS

Kidney function was not clearly associated with ovarian cancer risk. Larger studies are needed to evaluate possible histology specific associations. Given the suggestive trend for increased ovarian cancer risk in women with poor kidney function and high CRP, future work is needed, particularly in populations with a high prevalence of inflammatory conditions.

IMPACT

This study provided the first evaluation of markers of kidney function in relation to ovarian cancer risk.

Associations of HLA Polymorphisms with Chronic Kidney Disease in Japanese Rheumatoid Arthritis Patients

OBJECTIVES

The prevalence of chronic kidney disease (CKD) was reported to be higher in rheumatoid arthritis (RA) patients than in normal healthy individuals. Human leukocyte antigen (HLA) was associated with RA or CKD. Few studies on the association of HLA with CKD in RA have been reported. Here, we investigated the association of HLA polymorphisms with CKD in Japanese RA patients.

METHODS

HLA-DRB1 genotyping was conducted in 351 Japanese RA patients with CKD (estimated glomerular filtration rate [eGFR] lower than 60 [mL/min/1.73 m²]) and 959 without CKD (eGFR equal to or higher than 60 [mL/min/1.73 m²]). Associations of allele carrier frequencies of DRB1 with CKD were examined in the RA patients.

RESULTS

There was an association of DRB1*13:02 with CKD in RA, but this did not achieve statistical significance (p = 0.0265, odds ratio [OR] 1.70, pc = 0.7412, 95% confidence interval [CI] 1.09-2.64). The DR6 serological group was associated with CKD in RA (p = 0.0008, OR 1.65, 95% CI 1.24-2.20). A gene-dosage effect of DR6 was not detected. Logistic regression analysis showed that the association of DR6 with CKD in RA was independent of clinical characteristics.

CONCLUSIONS

The present study first revealed the independent predisposing association of DR6 with CKD in Japanese RA patients, although DR6 is known to be protective against RA. Our data suggest direct or indirect roles of HLA for the development of CKD in RA, but the mechanisms are not clear.

Sex differences in long-term effects of collagen-induced arthritis in middle-aged mice

Introduction: Rheumatoid arthritis (RA) is a chronic inflammatory disorder with high prevalence among middle-aged women. Collagen-induced arthritis (CIA) is the most widely used animal model of RA, however, sex differences and long-term effects of CIA in mice are poorly described in the literature. Aim: Therefore, the present study aimed to analyze the long-term effects of CIA on the joints of middle-aged mice of both sexes and to describe potential sex differences. Materials and methods: CIA was induced in middle-aged DBA/1J mice by immunization with bovine type II collagen and complete Freund's adjuvant. Saline was administered to control mice. Arthritis score assessment, plethysmometry, and thermal imaging of the joints were performed weekly for 15 weeks. Locomotor activity, micro-computed tomography, joint histology and biochemical analyses were performed at the end of the experiment. Results: Our results indicate a similar prevalence of arthritis in both sexes of mice-67% (8/12) of females and 89% (8/9) males with an earlier onset in males (day 14 vs. day 35). After the arthritis scores peaked on day 56 for males and day 63 for females, they steadily declined until the end of the experiment on day 105. A similar dynamics was observed in paw volume and temperature analyzing different aspects of joint inflammation. Long-term consequences including higher proteinuria (by 116%), loss of bone density (by 33.5%) and joint damage in terms of synovial hyperplasia as well as bone and cartilage erosions were more severe in CIA males compared to CIA females. There were no significant differences in locomotor activity between CIA mice and CTRL mice of any sex. Conclusion: This is the first study to describe the long-term effects of the CIA model in terms of sex differences in DBA/1J mice. Our results indicate sex differences in the dynamics, but not in the extent of arthritis. An earlier onset of arthritis and more severe consequences on joints, bones and kidneys were found in males. The underlying immune pathomechanisms responsible for the limited duration of the arthritis symptoms and the opposite sex difference in comparison to RA patients require further investigation.

[Renal manifestations in rheumatoid arthritis and spondylarthritis]

As systemic diseases it is not uncommon for inflammatory rheumatic diseases to exhibit renal involvement. In contrast to connective tissue diseases and vasculitis, in rheumatoid arthritis and spondylarthritis direct inflammatory manifestations in the sense of glomerulonephritis (GN) and autoimmune interstitial nephritis are rare. In these groups of diseases renal biopsies usually show mesangial proliferative GN and IgA nephropathy or less commonly membranous GN. These and secondary amyloid A (AA) amyloidosis are regularly associated with longer lasting disease activity and a poor prognosis; however, clinically more frequent and more relevant are other sequelae of chronic systemic inflammation, namely endothelial function disorder and the premature development of atherosclerosis, resulting in progressive kidney failure. This is accompanied by the undesired effects of antirheumatic treatment and renal complications of comorbidities.

OUP accepted manuscript

Background

We investigated the incidence of chronic kidney disease (CKD) progression and its factors relevant to patients with stable rheumatoid arthritis (RA).

Methods

We enrolled consecutive patients with RA who had initiated treatment with a biologic disease-modifying anti-rheumatic drug (bDMARD) at our institution and continued the same drug for >5 years between 2001 and 2016. Patients with CKD at bDMARD initiation were excluded. C-reactive protein (CRP) level, Clinical Disease Activity Index (CDAI) score and estimated glomerular filtration rate were measured every 6 months.

Results

We included 423 patients, with 196 on tumour necrosis factor inhibitors, 190 on tocilizumab and 37 on abatacept. Among these patients, 34 (8.0%) progressed to CKD within 5 years. The mean CRP level and CDAI score over 5 years were significantly lower in patients without CKD progression than in those with CKD progression (P < .001 and P = .008, respectively). Multivariable analysis revealed that age at bDMARD initiation [odds ratio (OR) 1.05, P = .002], non-steroidal anti-inflammatory drug use (OR 3.47, P = .004) and mean CRP >0.14 mg/dL (OR 5.89, P = .015) were independently associated with CKD progression, while tocilizumab use was associated with a decreased risk of CKD progression (OR 0.31, P = .027).

Conclusions

Controlling inflammation contributes to the inhibition of CKD progression in RA patients.

The effect of targeted rheumatoid arthritis therapeutics on systemic inflammation and anemia: analysis of data from the CorEvitas RA registry

BACKGROUND

To evaluate the effects of tumor necrosis factor inhibitors (TNFi), interleukin-6 receptor inhibitors (IL-6Ri), and Janus kinase inhibitors (JAKi) on hemoglobin (Hb) and C-reactive protein (CRP) levels in adults enrolled in CorEvitas (formerly Corrona), a large US rheumatoid arthritis (RA) registry.

METHODS

Patients who initiated TNFi, IL-6Ri, or JAKi treatment during or after January 2010, had Hb and CRP measurements at baseline and 6-month follow-up (± 3 months) and had continued therapy at least until that follow-up, through March 2020, were included in the analysis. Changes in Hb and CRP were assessed at month 6. Abnormal Hb was defined as < 12 g/dL (women) or < 13 g/dL (men); abnormal CRP was ≥ 0.8 mg/dL. Differences in Hb and CRP levels were evaluated using multivariable regression.

RESULTS

Of 2772 patients (TNFi, 65%; IL-6Ri, 17%; JAKi, 17%) evaluated, 1044 (38%) had abnormal Hb or CRP at initiation; an additional 252 (9%) had both abnormal Hb and CRP. At month 6, the IL-6Ri group had a greater Hb increase than the TNFi (mean difference in effect on Hb: 0.28 g/dL; 95% CI 0.19-0.38) and JAKi (mean difference in effect on Hb: 0.47 g/dL; 95% CI 0.35-0.58) groups, regardless of baseline Hb status (both p < 0.001). The CRP decrease at month 6 was greater with IL-6Ri compared with TNFi and JAKi, regardless of baseline CRP status (both p < 0.05).

CONCLUSION

These real-world results align with the mechanism of IL-6R inhibition and may inform treatment decisions for patients with RA.

Evaluating the Use of Hydroxychloroquine in Treating Patients With Rheumatoid Arthritis

Rheumatoid Arthritis (RA) is one of the most common autoimmune diseases present today. Although treatment options may differ among clinicians, a commonly prescribed treatment is hydroxychloroquine (HCQ), alone or in combination with other medications. HCQ has been studied for its immunomodulatory effects as well as its role in treating adverse conditions associated with RA. This systematic review examined the use of HCQ therapy in RA patients. A systematic search for relevant literature through PubMed, National Institute of Informatics, Japan (CiNii), and Science Direct databases were carried out in August 2021. Literature directly related to HCQ therapy for RA patients, RA-associated chronic kidney disease, and cardiovascular disease (including lipid profile) was considered relevant. HCQ associated retinopathic adverse effects were also selected for this review. Thirty-eight articles were found to be relevant, passed quality assessment, and were included in this review. Nine articles discussed HCQ therapy in comparison with other therapies (mainly methotrexate and sulfasalazine), but were contradictory in their outcomes, as were the seven papers that reviewed kidney function in RA patients with and without HCQ. Five articles credited better cardiovascular outcomes to RA patients taking HCQ. Sixteen articles studied the relationship between HCQ and retinal toxicity, providing insights into the risks associated with HCQ therapy. HCQ therapy was found not only to be beneficial in slowing the disease progression in RA patients but enhanced the effects of methotrexate in treating RA as well. Data strongly associates HCQ therapy with the mitigation of RA-related cardiovascular and kidney conditions. However, if HCQ is prescribed, it is imperative to be aware of the possible (although rare) retinopathic adverse effects associated with this therapy.

Impact of age on the efficacy and safety of peficitinib (ASP015K) for the treatment of rheumatoid arthritis

OBJECTIVES

To evaluate peficitinib efficacy and safety in Asian patients with rheumatoid arthritis (RA), stratified by age (≥20-<50, ≥50-<65, and ≥65 years).

METHODS

Efficacy data from two Phase 3 studies were analysed. Safety data from one Phase 2, two Phase 3, and one open-label extension study were pooled. Incidence rates per 100 patient-years of adverse events of special interest were calculated, and Cox proportional hazard analysis was conducted.

RESULTS

1052 patients received peficitinib for 2 years (median). Peficitinib demonstrated efficacy improvements versus placebo across all age categories. Incidence rates (95% confidence interval) per 100 patient-years for ≥20-<50, ≥50-<65, and ≥65 years were 0.8 (0.4, 1.9), 2.6 (1.8, 3.7), and 4.7 (3.1, 7.0) for serious infections and 3.7 (2.5, 5.4), 6.4 (5.0, 8.2), and 11.2 (8.5, 14.7) for herpes zoster-related disease, respectively. Twenty patients reported malignancies in pooled Phase 2/3 studies. Incidences of serious infections and herpes zoster-related disease increased significantly with age, but there was no association with baseline estimated glomerular filtration rate.

CONCLUSIONS

Peficitinib was efficacious in adult Asian RA patients of all ages. Age, but not estimated glomerular filtration rate, was associated with serious infections and herpes zoster-related disease, demonstrating the importance of an appropriate RA treatment strategy in older patients.

Evaluating a Living Donor With Rheumatoid Arthritis for a Recipient With End-Stage Renal Disease From Antineutrophil Cytoplasmic Antibodies Associated Vasculitis

A 60-year-old Caucasian female with sero-positive rheumatoid arthritis (RA) was evaluated as a potential kidney donor for her brother-in-law with end-stage kidney disease (ESKD) secondary to c-antineutrophil cytoplasmic antibody (c-ANCA) associated vasculitis (AAV) and membranous nephropathy (MN). With little to no data supporting or contradicting this unique scenario, in addition to the varying viewpoints expressed by the different specialists, our multidisciplinary transplant committee encountered a difficult decision of whether to approve a candidate with RA for a living kidney donation or not. As a result, we carried out a careful literature review addressing aspects of recipients' outcomes following kidney transplants from a living donor with RA, especially when the recipient has AAV, living donor's short- and long-term outcomes post kidney donation, renal disease in AAV and RA, and maintenance of disease remission.

Factors contributing to discrepant estimated glomerular filtration values measured by creatinine and cystatin C in patients with rheumatoid arthritis

This study aimed to clarify the factors underlying the discrepancy that has been noted between estimated glomerular filtration ratio (eGFR) measured using serum creatinine (Cr) and eGFR using serum cystatin C (CysC) in patients with rheumatoid arthritis (RA) and to identify those patients whose renal function should be evaluated using CysC. We retrospectively evaluated clinical features, disease activity, Steinbrocker radiological staging, and co-morbidities (diabetes mellitus, hypertension, dyslipidemia) in 238 RA patients. eGFR using serum creatinine (eGFR-Cr) and eGFR using serum cystatin C (eGFR-CysC) were calculated using the new Japanese coefficient-modified Modification of Diet in Renal Disease study equation. To clarify the cause(s) of differences of 20% or more between the two eGFRs, we divided our RA patients into Group A (eGFR-Cr/eGFR-CysC ≥ 1.2) and Group B (eGFR-Cr/eGFR-CysC < 1.2), and searched for factors independently related to Group A. Forty-five patients (18.9%) were assigned to Group A, and 193 (81.1%) to Group B. BMI (Odds Ratio [OR] 0.820, 95% confidence interval [CI] 0.675–0.996), Hb (OR 0.633, 95% CI 0.433–0.926), CK (OR 0.773 per 10 units, 95% CI 0.644–0.933), NSAID use (OR 0.099, 95% CI 0.020–0.494), diabetes mellitus (OR 6.024, 95% CI 1.508–24.390) and stage 4 Steinbrocker radiological stage (OR 10.309, 95% CI 2.994–35.714) were identified as independent relevant factors for Group A by a multifactorial analysis. Renal function in RA patients with low BMI, diabetes, anemia and low CK may be overestimated using eGFR-Cr alone, and such patients need to be evaluated using eGFR-CysC.

[Immunity and tubular dysfunction in case of systemic disease]

The immune renal tubular diseases are known since five decades, but their prevalence remains to be defined. They are caused by humoral and cellular effectors of innate and adaptative immunities on several targets of the renal tubule: protein channels, co or counter transporters, luminal or cytosolic enzymes, tight junctions. Genetic or epigenetic variations are also involved. Clinical manifestations are various and make the diagnosis difficult. They can precede the causal affection and they worsen the prognosis. The classical model consists in hypokalemic tubular distal acidosis observed in Sjögren's syndrome which illustrates the auto-immune epithelitis concept. Cellular immunity can act through other ways, like tertiary lymphoid neogenesis in systemic lupus. Humoral immunity through autoantibodies targets several membrane, cytosolic or nuclear proteins, causing specific tubular dysfonctions. It is also implied in the epithelial-mesenchymal transition of tubular cells. Innate immunity through cytokines may be involved. Treatment consists in electrolytic disorders correction and immunosupppressive medication: the choice should be guided at best by physiopathology.

Dietary Fibers (Gum Arabic) Supplementation Modulates Hepatic and Renal Profile Among Rheumatoid Arthritis Patients, Phase II Trial

Background: Rheumatoid arthritis (RA) is an autoimmune disease that mainly affects the synovial joints with systemic manifestations. RA has a major impact on liver and kidney functions as part of the disease pathogenesis or as a sequel of disease medications or, mostly, both of them. The kidney and liver involvement increases the RA morbidity and mortality. Nowadays, dietary interventions are proposed as potential modifiers for disease severity. Gum Arabic (GA) is acacia senegal exudates; it is soluble fiber with prebiotic properties. GA has been discovered to be protective against experimental nephrotoxicity and hepatotoxicity, with comparable findings in human studies. This article addresses the effect of GA on hepatic and renal profile among RA patients.

Methods: Forty patients aged 18–70 received GA daily for 12 weeks as a single dose of 30 g. The liver enzymes, total protein level, serum albumin, serum globulin level, urea, creatinine, and serum electrolytes have been measured as a baseline after 4 weeks and by the end of the study. Cobas C311 (Roche, Germany) automated chemistry analyzer directly determined the values for total protein, albumin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and creatinine. The study ethically has been approved by the Ethical Committee of the National Medicines and Poisons Board. Trial Registration Identifier: NCT02804581.

Results: Regarding the liver enzymes, GA has significantly decreased the liver enzymes apart from alkaline phosphatase, which showed no significant change. In contrast, GA has increased the serum albumin level with a minor impact on the serum globulin level. Furthermore, GA has also significantly decreased the level of urea (P = 0.0001) and level of Sodium (P = 0.002) with nonsignificant change on creatinine and potassium concentrations.

Conclusion: GA presents hepatic and renal protective effects among RA patients, evidenced by the significant reduction of urea and liver enzymes. Thus, it can be recommended as a dietary supplement for RA patients. Nonetheless, we recommend further investigation to support our findings.

Risk of higher dose methotrexate for renal impairment in patients with rheumatoid arthritis

Renal impairment is a major concern in patients taking high-dose methotrexate (MTX) for malignancy, but it has not been fully explored in rheumatoid arthritis (RA) patients taking low-dose MTX. This study aimed to elucidate the dose-dependent effects of MTX on the renal function of patients with RA. We retrospectively reviewed 502 consecutive RA patients who were prescribed MTX for ≥ 1 year at Okayama University Hospital between 2006 and 2018. The primary outcome was the change in estimated glomerular filtration rate (eGFR) over 1 year. The association between MTX dosage (< 8, 8-12, and ≥ 12 mg/week) and the change in eGFR was evaluated using multiple linear regression analysis with adjustment for possible confounding factors including age, sex, disease duration, body weight, comorbidity, baseline eGFR, concomitant treatment, and disease activity. Mean patient age was 63 years; 394 (78%) were female. Median disease duration was 77 months, while mean MTX dosage was 8.6 mg/week. The last 1-year change of eGFR (mean ± SD) in patients treated with MTX < 8 (n = 186), 8-12 (n = 219), ≥ 12 mg/week (n = 97) decreased by 0.2 ± 7.3, 0.6 ± 8.6, and 4.5 ± 7.9 mL/min/1.73 m²/year, respectively (p < 0.0001). After adjustment for the confounding factors, MTX ≥ 12 mg/week was still correlated with a decrease in 1-year eGFR (beta-coefficient: - 2.5; 95% confidence interval, - 4.3 to - 0.6; p = 0.0089) in contrast to MTX 8-12 mg/week. Careful monitoring of renal function is required in patients with MTX ≥ 12 mg/week over the course of RA treatment regardless of disease duration.

Associations between Multimorbidity and Physical Performance in Older Chinese Adults

Background: Evidence on the association between physical performance and multimorbidity is scarce in Asia. This study aimed to identify multimorbidity patterns and their association with physical performance among older Chinese adults. Methods: Individuals aged ≥60 years from the China Health and Retirement Longitudinal Study 2011-2015 (N = 10,112) were included. Physical performance was measured by maximum grip strength (kg) and average gait speed (m/s) categorized as fast (>0.8 m/s), median (>0.6-0.8 m/s), and slow (≤0.6 m/s). Multimorbidity patterns were explored using exploratory factor analysis. Generalized estimating equation was conducted. Results: Four multimorbidity patterns were identified: cardio-metabolic, respiratory, mental-sensory, and visceral-arthritic. An increased number of chronic conditions was associated with decreased normalized grip strength (NGS). Additionally, the highest quartile of factor scores for cardio-metabolic (β = -0.06; 95% Confidence interval (CI) = -0.07, -0.05), respiratory (β = -0.03; 95% CI = -0.05, -0.02), mental-sensory (β = -0.04; 95% CI = -0.05, -0.03), and visceral-arthritic (β = -0.04; 95% CI = -0.05, -0.02) patterns were associated with lower NGS compared with the lowest quartile. Participants with ≥4 chronic conditions were 2.06 times more likely to have a slow gait speed. Furthermore, the odds ratios for the highest quartile of factor scores of four patterns with slow gait speed compared with the lowest quartile ranged from 1.26-2.01. Conclusion: Multimorbidity was related to worse physical performance, and multimorbidity patterns were differentially associated with physical performance. A shift of focus from single conditions to the requirements of a complex multimorbid population was needed for research, clinical guidelines, and health-care services. Grip strength and gait speed could be targeted to routinely measure clinical performance among older adults with multimorbidity, especially mental-sensory disorders, in clinical settings.

[Clinicopatological variants and risk factors for chronic kidney disease in rheumatoid arthritis]

Recent studies have shown a high risk of chronic kidney disease and associated cardiovascular complications in patients with rheumatoid arthritis (RA), which determines the prognosis. However, the prevalence of chronic kidney disease (CKD) in RA has not been established in the Russians.

AIM

Study was to examine the prevalence, risk factors and histological variants of CKD in RA.

MATERIALS AND METHODS

180 patients with rheumatoid arthritis were observed in the Tareev clinic of nephrology, for the period from 2014 to 2019 years. Age, gender, duration of RA, drug therapy, ESR, CRP, DAS28, renal function, proteinuria, histological variants were analyzed. Of the common population risk factors for CKD arterial hypertension, weight index, serum lipids and glucose levels were also assessed.

RESULTS

The prevalence of CKD in RA was 19.7%. Age, presence and stage of arterial hypertension, an increase in body mass index, as well as high rates of disease activity ESR, CRP, DAS28 score and duration of RA were risk factors of CKD in RA. Age, duration of the disease, stage of AH and hypercholesterolemia were risk factors in multifactorial regression analysis. Amyloidosis was the most common histologic pattern (50.0%), followed by chronic glomerulonephritis (30.4%) and tubulo-interstitial nephritis (19.6%). Among chronic glomerulonephritis mesangial glomerulonephritis was the most frequent. Renal amyloidosis was associated with a duration of RA, presence of systemic symptoms and CRP level. An isolated decrease in GFR of less than 60 ml/min was detected in 31 (36.0%) out of 86 patients. Сonclusion. The risk factors for CKD in patients with RA are activity and duration of the disease In addition to common population factors. Amyloidosis was the most common histologic pattern associated with duration of RA and inflammatory proteins levels.

Repercussions of adjuvant-induced arthritis on body composition, soleus muscle, and heart muscle of rats

This study investigated the repercussions of adjuvant-induced arthritis (AIA) on body composition and the structural organization of the soleus and cardiac muscles, including their vascularization, at different times of disease manifestation. Male rats were submitted to AIA induction by intradermal administration of 100 μL of Mycobacterium tuberculosis (50 mg/mL), in the right hind paw. Animals submitted to AIA were studied 4 (AIA4), 15 (AIA15), and 40 (AIA40) days after AIA induction as well as a control group of animals not submitted to AIA. Unlike the control animals, AIA animals did not gain body mass throughout the evolution of the disease. AIA reduced food consumption, but only on the 40th day after induction. In the soleus muscle, AIA reduced the wet mass in a time-dependent manner but increased the capillary density by the 15th day and the fiber density by both 15 and 40 days after induction. The diameter of the soleus fiber decreased from the 4th day after AIA induction as well as the capillary/fiber ratio, which was most evident on the 40th day. Moreover, AIA induced slight histopathological changes in the cardiac muscle that were more evident on the 15th day after induction. In conclusion, AIA-induced changes in body composition as well as in the soleus muscle fibers and vasculature have early onset but are more evident by the 15th day after induction. Moreover, the heart may be a target organ of AIA, although less sensitive than skeletal muscles.

Subjective Age and Cystatin C Among Older Adults

OBJECTIVE

Cystatin C (CysC) is a marker of kidney function that is relevant for the health and cognition of older adults. Little is known about the link between psychological factors and CysC. Therefore, the present study examined whether subjective age is related to CysC level and changes in CysC over time.

METHOD

Participants were 5,066 individuals drawn from the Health and Retirement Study aged from 50 to 107 years (60% women, mean age = 69.36 years, SD = 9.54). They provided data on subjective age, demographic covariates, and CysC at baseline. CysC was assessed again 4 years later.

RESULTS

Analysis revealed that an older subjective age was related to higher level of CysC at baseline and to an increase in CysC over 4 years, controlling for demographic factors. An older subjective age was also related to higher risk of exceeding the clinical threshold of CysC at baseline and 4 years later. Additional analysis revealed that disease burden, depressive symptoms, physical inactivity, and BMI partly mediated these associations.

CONCLUSION

The present study provides new evidence on the role of subjective age as a psychological factor associated with individuals' risk of kidney dysfunction, an association beyond chronological age.

Associations Between Somatic Multimorbidity Patterns and Depression in a Longitudinal Cohort of Middle-Aged and Older Chinese

OBJECTIVES

Depressive symptoms are commonly seen among patients with multiple chronic somatic conditions, or somatic multimorbidity (SMM); however, little is known about the relationships between depressive symptoms and different SMM combinations. Our study aimed to delineate the patterns of SMM and their longitudinal associations with depressive symptoms among a nationally representative sample of middle-aged and older Chinese adults.

DESIGN

We employed a longitudinal design.

SETTING AND PARTICIPANTS

Older adults (N = 10,084) aged ≥45 years from the China Health and Retirement Longitudinal Study 2011-2015 participated (mean age = 57.7 years at baseline; 53.3% men).

METHODS

Sixteen chronic somatic conditions were ascertained at baseline via questionnaires. Depression was assessed with the Center for Epidemiological Studies Depression Scale at baseline and during follow-up. Patterns of SMM were identified via exploratory factor analyses. Generalized estimating equations were used to evaluate the longitudinal associations between patterns of SMM and the presence of depressive symptoms at follow-up.

RESULTS

Compared with participants with no somatic condition, those with 1, 2, and 3 or more somatic conditions had a 21%, 66%, and 111% greater risk, respectively, for the presence of depressive symptoms. Increased factor scores for 4 patterns identified, cardio-metabolic pattern [adjusted odds ratio (AOR) 1.12, 95% confidence interval (CI) 1.06, 1.20], respiratory pattern (AOR 1.25, 95% CI 1.17, 1.33), arthritic-digestive-visual pattern (AOR 1.29, 95% CI 1.22, 1.37), and hepatic-renal-skeletal pattern (AOR 1.09, 95% CI 1.02, 1.16), were all associated with a higher risk of having depressive symptoms.

CONCLUSIONS AND IMPLICATIONS

All SMM patterns were independently associated with depression among middle-aged and older Chinese adults, with greater odds for people with comorbid arthritic-digestive-visual conditions and respiratory conditions. Clinical practitioners should treat the middle-aged and older population under a multiple-condition framework combining SMM and mental disorders.

Preparation of Chondroitin Sulfate-Glycyl-Prednisolone Conjugate Nanogel and Its Efficacy in Rats with Ulcerative Colitis

A conjugate between chondroitin sulfate (CS) and glycyl-prednisolone (GP), named CS-GP, was produced by carbodiimide coupling at a high GP/CS ratio. CS-GP was not water-soluble and gave a nanogel (NG) in aqueous solution. Two types of nanogels, NG(I) and NG(II), with prednisolone (PD) contents of 5.5 and 21.1% (w/w), respectively, were obtained. They had particle sizes of approximately 280 and 570 nm, respectively, and showed negative ζ-potentials of approximately -40 mV. The PD release rate was slower in the nanogels than in a solution of CS-GP with a PD content of 1.4% (w/w). The PD release rate was slower in NG(II) than in NG(I), and was elevated at pH 7.4 than at pH 6.8. NG(II) was applied in vivo to rats with trinitrobenzene sulfonic acid (TNBS)-induced colitis, and its therapeutic efficacy and pharmacokinetic features were investigated. The therapeutic efficacy of NG(II) was slightly better than that of PD alone. Drug delivery to the lower intestines was enhanced with NG(II). The CS-GP nanogel has potential as a potent DDS for the treatment of ulcerative colitis.

Trends of Cardiac Complications in Patients With Rheumatoid Arthritis: Analysis of the United States National Inpatient Sample; 2005-2014

BACKGROUND

Rheumatoid arthritis (RA) is a chronic inflammatory condition. Chronic inflammation is associated with atherosclerosis, hypertension, diabetes, chronic obstructive pulmonary disease (COPD), chronic kidney disease. But sparse data are available regarding the trends of cardiovascular diseases and complications in RA. We conducted a National Inpatient Sample database analysis to demonstrate the trends of cardiac complications in patients with RA.

METHODS

We used National Inpatient Sample data from 2005 to 2014 to identify admissions with the diagnosis of RA and identified who had associated cardiovascular complications also. The International Classification of Diseases-9th Revision-Clinical Modification codes were used for the diagnoses of RA; congestive heart failure (CHF), acute myocardial infarction (AMI), and atrial fibrillation (AF).

RESULTS

A statistically significant increasing trend of AMI, CHF, and AF was found. Independent predictors of mortality in RA patients with AMI were age (OR 1.03, CI 1.02-1.04; P < 0.001), COPD (OR 1.67, CI 1.40-2.00; P < 0.001), cerebrovascular disease (OR 2.207, CI 1.71-2.86; P < 0.001), renal disease (OR 1.42, CI 1.16-1.75; P = 0.001), and alcohol abuse (OR 2.73, CI 1.73-4.32; P < 0.001). Independent predictors of mortality in RA patients with CHF were age (odds ratio [OR] 1.02, confidence interval [CI] 1.017-1.024; P < 0.001]), COPD (OR 1.09, CI 1.01-1.18; P = 0.023), cerebrovascular disease (OR 1.67, CI 1.44-1.95; P < 0.001), renal disease (OR 1.16, CI 1.07-1.27; P = 0.001). Independent predictors of mortality in RA patients with AF were age (OR 1.02, CI 1.02-1.03; P < 0.001), race (OR 1.16, CI 1.02-1.31; P = 0.022), COPD (OR 1.56, CI 1.42-1.71; P < 0.001), peripheral arterial disease (OR 1.34, CI 1.16-1.53; P < 0.001), cerebrovascular disease (OR 2.27, CI 1.0-2.58; P < 0.001), renal disease (OR 1.60, CI 1.44-1.80; P < 0.001). The mortality trend has increased significantly in the CHF (P = 0.025) and AF (P = 0.042) groups during this study period.

CONCLUSIONS

We have found a significant increase in trend of cardiovascular complications in RA patients. The proportion of patients, with cardiovascular comorbidities, have also been increased significantly.

Impaired renal functions in Pakistani cohort of rheumatoid arthritis

Objective

To determine the frequency of impaired renal functions and hypertension in rheumatoid arthritis.

Methods

This study was conducted between May 1^st 2018 to February 1^st 2019 at Rheumatology Division, Department of Medicine Central Park Medical College Lahore, total 260 study participants were selected, demographic detail were asked in detail, disease duration of RA and hypertension, DMARD's, self-use NSAID's,/hakeem medications, smoking were asked in detail, BMI and blood pressure were measured,5 ml of blood was taken by trained phlebotomist, and sent for the estimation of serum urea and creatinine on (COBAS-III) machine, after availability of results each individuals eGFR (creatinine clearance) was calculated by Cockroft Gualt_(CG) and Modification in diet in renal disease method (MDRD).

Results

In this study the mean age of study participants was 42.4 (± 9.5) years with disease duration of 7.7(±4.8) years, prevalence of Impaired renal functions of 14.6% (n=38) and hypertension in 53.5% (n=139).Regression analysis shows there is significant association between hypertension, smoking and self/hakeem medications with impaired renal functions (p-0.5). Kappa analysis shows both (MDRD & CG methods) had uniformity in picking up cases of impaired renal functions 75.6% (p-0.05).

Conclusion

In RA decline in renal functions is seen with self-use NSAID's/hakeem medications along with other modifiable factors like smoking and hypertension, while conventional DMARD's don't show association with decline. There is very high prevalence of hypertension in rheumatoid arthritis.

Factors associated with a reduction in glomerular filtration rate in patients with chronic obstructive pulmonary disease

Aim. Analysis of factors associated with reduced glomerular filtration rate (GFR) in patients with chronic obstructive pulmonary disease (COPD). Materials and methods. The study included 198 patients with COPD 1-4 degrees of severity (GOLD 2014), who were on examination and treatment in Krasnodar Regional clinical hospital № 2. The control group consisted of 28 healthy volunteers, comparable in age and sex. In addition to clinical research, all patients, we calculated GFR according to the formula CKD-EPI based on cystatin C serum (GFRcys). The contribution of the factors in the risk of developing CKD was determined using multivariate linear regression analysis, as dependent variable used the value of GFRcys. Results and discussion. It was found that more than half (51.5%) of patients with COPD have a decrease in GFRcys

Sleep and the Risk of Chronic Kidney Disease: A Cohort Study

STUDY OBJECTIVES

Little information is available regarding the effect of sleep on the development of chronic kidney disease (CKD). This large-cohort study aimed to investigate the association between sleep and the incidence of CKD.

METHODS

We recruited 194,039 participants without CKD aged 20 years or older between 1996 and 2014. Incident CKD was defined as an estimated glomerular filtration rate of < 60 mL/min/1.73 m². Information about sleep duration and quality was obtained from a questionnaire and used to generate a score reflecting the sleep profile. Cox proportional hazards regression models were used to calculate the hazard ratio (HR) and 95% confidence interval (CI) for CKD associations with sleep duration, quality, and score categories.

RESULTS

Regarding sleep duration, participants who slept for fewer than 4 hours (HR 1.45, 95% CI 1.22-1.71), 4 to 6 hours (1.07, 1.02-1.14), or more than 8 hours (1.12, 1.04-1.21) had an increased risk of incident CKD, compared to those who slept 6 to 8 hours. Regarding sleep quality, participants who fell asleep but awoke easily (1.13, 1.07-1.19), had difficulty falling asleep (1.14, 1.06-1.22), or used sleeping pills or sedatives (1.14, 1.20-1.66) had a higher risk of incident CKD, compared to those who slept well. Furthermore, participants with sleep scores of 4 to 6 (1.07, 1.02-1.13) and less than 4 (1.61, 1.37-1.89) had an increased risk of incident CKD, compared to those with a sleep score higher than 6.

CONCLUSIONS

A poor sleep profile is associated with increased risk of CKD development. Therefore, sleep duration and quality should be considered when developing strategies to improve sleep and thus prevent CKD.

COMMENTARY

A commentary on this article appears in this issue on page 371.

Should a patient with rheumatoid arthritis be a kidney donor?

We cared for a woman with sero-positive rheumatoid arthritis (RA), in clinical remission on oral methotrexate (MTX) and hydroxychloroquine, who wished to donate a kidney to a brother with end-stage renal disease (ESRD). We could find scant literature about this unusual clinical circumstance, and therefore review pertinent aspects of renal disease in RA, perioperative medical management, maintenance of disease remission, outcomes for RA patients who have donated kidneys, and relevant ethical issues. Renal complications in RA are not uncommon, with as many as 50% of patients at risk of reduced eGFR. This reflects anti-rheumatic and analgetic medication use (non-steroidal anti-inflammatory drugs, acetaminophen, DMARDs [cyclosporine and, historically, D-penicillamine and gold compounds], and others), glomerulitis, interstitial nephritis, complicating Sjogren's syndrome, vasculitis, or amyloidosis, and/or emergence of an "overlap" syndrome or other rheumatic disorder. The literature suggests that MTX need not be interrupted for surgery. The risk of perioperative infection to our patient would be low and remission should be sustained. We are aware of one study of six patients with RA who donated kidneys; they experienced no complications, ESRD, or deaths after a median follow-up of 8.2 years. Our ethical responsibilities are to balance patient autonomy of decision-making while assuring clinical beneficence and minimizing potential maleficence. Our perspective was that it would not be unreasonable to support this patient donating a kidney if, when fully informed, that remained her wish.

Hydroxychloroquine Use and Risk of CKD in Patients with Rheumatoid Arthritis

BACKGROUND AND OBJECTIVES

Hydroxychloroquine is widely used in patients with rheumatoid arthritis. However, large-scale studies examining the long-term effects of hydroxychloroquine on the development of kidney disease in patients with rheumatoid arthritis are lacking. We aimed to assess the long-term association of hydroxychloroquine use with the risk of developing CKD in this population.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We conducted an observational cohort study for patients with newly diagnosed rheumatoid arthritis who were enrolled prospectively in Taiwan's National Health Insurance Research Database between January 1, 2000 and December 31, 2013. We used multivariable Cox proportional hazard regression to analyze the association of hydroxychloroquine use with incident CKD.

RESULTS

A total of 2619 patients, including 1212 hydroxychloroquine users and 1407 hydroxychloroquine nonusers, were analyzed. Incident CKD was reported in 48 of 1212 hydroxychloroquine users and 121 of 1407 hydroxychloroquine nonusers. The incidence rate of CKD was lower in hydroxychloroquine users than in hydroxychloroquine nonusers (10.3 versus 13.8 per 1000 person-years). After multivariable adjustment, hydroxychloroquine users still had a lower risk of incident CKD (adjusted hazard ratio, 0.64; 95% confidence interval, 0.45 to 0.90; P=0.01) than hydroxychloroquine nonusers. The lower risk of subsequent CKD development was dose dependent and consistent across subgroup analyses.

CONCLUSIONS

Hydroxychloroquine use in patients with newly diagnosed rheumatoid arthritis is associated with a significantly lower risk of incident CKD compared with in nonusers.

Treatment of rheumatoid arthritis with biologic agents lowers the risk of incident chronic kidney disease

Rheumatoid arthritis is associated with reduced kidney function, possibly due to chronic inflammation or the use of nephrotoxic therapies. However, little is known about the effects of using the newer novel non-nephrotoxic biologic agents on the risk of incident chronic kidney disease (CKD). To study this we used a cohort of 20,757 United States veterans diagnosed with rheumatoid arthritis with an estimated glomerular filtration rate (eGFR) of 60 mL/min/1.73m² or more, recruited between October 2004 and September 2006, and followed through 2013. The associations of biologic use with incident CKD (eGFR under 60 with a decrease of at least 25% from baseline, and eGFR under 45 mL/min/1.73m²) and change in eGFR (<-3, -3 to <0 [reference], and ≥0 mL/min/1.73m²/year) were examined in propensity-matched patients based on their likelihood to initiate biologic treatment, using Cox models and multinomial logistic regression models, respectively. Among 20,757 patients, 4,617 started biologic therapy. In the propensity-matched cohort, patients treated (versus not treated) with biologic agents had a lower risk of incident CKD (hazard ratios 0.95, 95% confidence interval [0.82-1.10] and 0.71 [0.53-0.94] for decrease in eGFR under 60 and under 45 mL/min/1.73m², respectively) and progressive eGFR decline (multinomial odds ratios [95% CI] for eGFR slopes <-3 and ≥0 [versus -3 to <0] mL/min/1.73m²/year, 0.67 [0.58-0.79] and 0.76 [0.69-0.83], respectively). A significant deceleration of eGFR decline was also observed after biologic administration in patients treated with biologics (-1.0 versus -0.4 [mL/min/1.73m²/year] before and after biologic use). Thus, biologic agent administration was independently associated with lower risk of incident CKD and progressive eGFR decline.

Retrospective cohort study on risk of hearing loss in patients with rheumatoid arthritis using claims data

OBJECTIVES

Population studies on hearing loss (HL) associated with rheumatoid arthritis (RA) are lacking. This study investigated the risk of developing HL in patients with RA using a nationwide population cohort.

SETTING

The population-based insurance claims data in the Taiwan National Health Insurance Research Database.

DESIGN

Retrospective cohort study followed up RA cohort and control cohort without RA frequency matched by sex, age and diagnosis year.

STUDY POPULATION

18 267 patients with RA newly diagnosed in 2000-2006 and 73 068 controls without RA.

MAIN OUTCOMES

Incidences of HL by the end of 2011 and the RA cohort to non-RA cohort HRs after adjusting for sex, age and comorbidities.

RESULTS

The HL incidence was higher in the RA cohort than in the non-RA cohort (3.08 vs 1.62 per 1000 person-years), with an adjusted HR (aHR) of 1.91 (95% CI 1.70 to 2.14) for the RA cohort relative to the non-RA cohort after controlling for age, sex and comorbidities. Men and the elderly are at a higher risk. Cardiovascular comorbidities were associated with a further increased HL risk for patients with RA. Medications were associated with reduced HL incidence; patients with RA who used non-steroidal anti-inflammatory drugs (NSAIDs) had an aHR of 0.12 (95% CI 0.07 to 0.20), compared with non-users.

CONCLUSIONS

This study demonstrates that patients with RA are at an increased risk of developing HL. Findings highlight the need of disease-modifying treatment and scheduled auditory examinations for HL prevention and early detection for patients with RA.

Prevalence of and factors associated with renal dysfunction in rheumatoid arthritis patients: a cross-sectional study in community hospitals

This study was designed to determine the prevalence of renal dysfunction in rheumatoid arthritis (RA) patients and to identify factors associated with this complication. Between October 2014 and May 2015, we consecutively recruited RA patients at rheumatology sections of community hospitals in Japan. Each patient's absolute and body surface area (BSA)-indexed estimated glomerular filtration rate (eGFR) values were measured twice over a 3-month interval. Renal dysfunction was defined as absolute eGFR or BSA-indexed eGFR < 60. Albuminuria and hematuria were also recorded. Associations between renal dysfunction and possible risk factors were examined by multivariate logistic regression analyses. A total of 1908 outpatients with RA were included in this study. The prevalence of renal dysfunction based on absolute eGFR and BSA-indexed eGFR was 33.8 and 18.6%, respectively. Albuminuria was observed in 8.1% of this patient cohort, and the prevalence of hematuria was 7.5%. Advanced age (odds ratio [OR] 7.24, p < 0.001), female sex (OR 3.12, p < 0.001), hypertension (OR 2.22, p < 0.001), and obesity (OR 0.59, p < 0.001) were independently associated with the risk of absolute eGFR-based renal dysfunction. Advanced age (OR 5.19, p < 0.001) and hypertension (OR 3.05, p < 0.001) also had associations with BSA-indexed eGFR-based renal dysfunction. RA duration, stages, severity, and cumulative steroid dose were considered significant risk factors in univariate analyses, but their associations were less potent after adjustment for other covariates. Renal dysfunction is relatively common in RA patients and is mainly associated with advanced age and hypertension but not with RA-related factors.