The vitamin D receptor is present in caveolae-enriched plasma membranes and binds 1 alpha,25(OH)2-vitamin D3 in vivo and in vitro

The steroid hormone 1 alpha,25(OH)(2)-vitamin D(3) (1,25D) regulates gene transcription through a nuclear receptor [vitamin D receptor (VDR)] and initiation of rapid cellular responses through a putative plasma membrane-associated receptor (VDR(mem)). This study characterized the VDR(mem) present in a caveolae-enriched membrane fraction (CMF), a site of accumulation of signal transduction agents. Saturable and specific [(3)H]-1,25D binding in vitro was found in CMF of chick, rat, and mouse intestine; mouse lung and kidney; and human NB4 leukemia and rat ROS 17/2.8 osteoblast-like cells; in all cases the 1,25D K(D) binding dissociation constant = 1-3 nM. Our data collectively support the classical VDR being the VDR(mem) in caveolae: 1) VDR antibody immunoreactivity was detected in CMF of all tissues tested; 2) competitive binding of [(3)H]-1,25D by eight analogs of 1,25D was significantly correlated between nuclei and CMF (r(2) = 0.95) but not between vitamin D binding protein (has a different ligand binding specificity) and CMF; 3) confocal immunofluorescence microscopy of ROS 17/2.8 cells showed VDR in close association with the caveolae marker protein, caveolin-1, in the plasma membrane region; 4) in vivo 1,25D pretreatment reduced in vitro [(3)H]-1,25D binding by 30% in chick and rat intestinal CMF demonstrating in vivo occupancy of the CMF receptor by 1,25D; and 5) comparison of [(3)H]-1,25D binding in VDR KO and WT mouse kidney tissue showed 85% reduction in VDR KO CMF and 95% reduction in VDR KO nuclear fraction. This study supports the presence of VDR as the 1,25D-binding protein associated with plasma membrane caveolae.

Presence of a truncated form of the vitamin D receptor (VDR) in a strain of VDR-knockout mice

As part of our studies on the membrane-initiated actions of 1alpha,25-dihydroxyvitamin D(3) [1alpha,25(OH)(2)D(3)] and its localization in caveolae membrane fractions, we used a vitamin D receptor (VDR)-knockout (KO) mouse model to study the binding of [(3)H]-1alpha,25(OH)(2)D(3) in the presumed absence of the VDR. In this mouse model, known as the Tokyo strain, the second exon of the VDR gene, which encodes the first of the two zinc fingers responsible for DNA binding, was removed, and the resulting animals have been considered to be VDR-null mice. To our surprise, several tissues in these KO mice showed significant (5-50% of that seen in wild-type animals) specific binding of [(3)H]-1alpha,25(OH)(2)D(3) in nuclear and caveolae membrane fractions. The dissociation constants of this binding in samples from VDR-KO and wild-type mice were indistinguishable. RT-PCR analysis of intestinal mRNA from the VDR-KO animals revealed an mRNA that lacks exon 2 but contains exons 3-9 plus two 5'-untranslated exons. Western analysis of intestinal extracts from VDR-KO mice showed a protein of a size consistent with the use of Met52 as the translational start site. Transfection of a plasmid construct containing the sequence encoding the human analog of this truncated form of the receptor, VDR(52-C), into Cos-1 cells showed that this truncated form of the receptor retains full [(3)H]-1alpha,25(OH)(2)D(3) binding ability. This same construct was inactive in transactivation assays using the osteocalcin promoter in CV1 cells. Thus, we have determined that this widely used strain of the VDR-KO mouse can express a form of the VDR that can bind ligand but not activate gene transcription.

Distinct fatty acid signatures in infrapatellar fat pad and synovial fluid of patients with osteoarthritis versus rheumatoid arthritis

Background

Infrapatellar fat pad (IFP) has recently emerged as a potential source of inflammation in knee arthropathies. It has been proposed to be one source of adipocytokines, fatty acids (FA), and FA-derived lipid mediators that could contribute to the pathophysiological processes in the knee joint. Alterations in synovial fluid (SF) lipid composition have been linked to both osteoarthritis (OA) and rheumatoid arthritis (RA). The aim of the present study was to compare the FA signatures in the IFP and SF of RA and OA patients.

Methods

Pairs of IFP and SF samples were collected from the same knees of RA (n = 10) and OA patients (n = 10) undergoing total joint replacement surgery. Control SF samples (n = 6) were harvested during diagnostic or therapeutic arthroscopic knee surgery unrelated to RA or OA. The FA composition in the total lipids of IFP and SF was determined by gas chromatography with flame ionization and mass spectrometric detection.

Results

Arthropathies resulted in a significant reduction in the SF proportions of n-6 polyunsaturated FA (PUFA), more pronouncedly in OA than in RA. OA was also characterized with reduced percentages of 22:6n-3 and lower product/precursor ratios of n-3 PUFA. The proportions of total monounsaturated FA increased in both RA and OA SF. Regarding IFP, RA patients had lower proportions of 20:4n-6, total n-6 PUFA, and 22:6n-3, as well as lower product/precursor ratios of n-3 PUFA compared to OA patients. The average chain length of SF FA decreased in both diagnoses and the double bond index in OA.

Conclusions

The observed complex alterations in the FA signatures could have both contributed to but also limited the inflammatory processes and cartilage destruction in the RA and OA knees.

Rheumatoid arthritis antigens homocitrulline and citrulline are generated by local myeloperoxidase and peptidyl arginine deiminases 2, 3 and 4 in rheumatoid nodule and synovial tissue

Background

Seropositive rheumatoid arthritis (RA) is characterized by autoantibodies binding to citrullinated and homocitrullinated proteins. We wanted to study the expression patterns of these disease-associated protein forms and if the rheumatoid nodule and synovial tissue itself contain biologically active levels of citrullinating peptidyl arginine deiminases 2, 3 and 4 and homocitrullination-facilitating neutrophil enzyme myeloperoxidase.

Method

Total of 195 synovial samples from metatarsal joints from five ACPA/RF-positive RA patients (n = 77), synovial samples from knees of eight seropositive RA (n = 60), seven seronegative RA (n = 33) and five osteoarthritis (n = 25) patients were analyzed for citrulline and homocitrulline contents using HPLC. The location of citrulline- and homocitrulline-containing proteins, PAD 2, 3, 4 and myeloperoxidase were shown by immunostaining. Myeloperoxidase and citrulline- or homocitrulline-containing proteins were stained on Western blot.

Results

Overall, necrosis was frequent in metatarsals of seropositive RA and absent in seronegative RA and osteoarthritis patients. In histological analysis, there was a significant local patterning and variation in the citrulline and homocitrulline content and it was highest in metatarsal synovial tissues of seropositive RA patients. We found peptidyl arginine deiminase 2, 3 and 4 in the lining and sublining layers of intact synovial tissue. Myeloperoxidase was found locally around necrotic areas. The tissues with necrosis contained the highest levels of citrulline and homocitrulline.

Conclusions

Rheumatoid nodules and synovia contain significant amount of PAD2, 3 and 4 and myeloperoxidase enzymes. These enzymes could explain the levels of citrulline and homocitrulline in seropositive RA synovial and rheumatoid nodule tissues especially around necrotic tissue.

1,25(OH)2D3 and calcipotriol, its hypocalcemic analog, exert a long-lasting anti-inflammatory and anti-proliferative effect in synoviocytes cultured from patients with rheumatoid arthritis and osteoarthritis

OBJECTIVES

We investigated the effects of 1,25-dihydroxy vitamin D₃ (1,25(OH)₂D₃), i.e. biologically active vitamin D and calcipotriol, a vitamin D analog, on growth and secretion of inflammatory mediators in synovial stromal cells (SSC) of patients with rheumatoid arthritis (RA) or osteoarthritis (OA).

METHODS

Synovial stromal cells (SSC) isolated during knee prosthesis surgery from four patients with RA and four with OA were exposed to 1,25(OH)₂D₃ or calcipotriol with or without stimulation of cells with IL-1β or TNF-α. The proliferation of cells was studied by MTT assay. Levels of cytokines were analyzed by a magnetic bead-based multiplex assay (a panel of 27 important cytokines and IL-6 alone) and RT-PCR was used to validate the concentrations of the key cytokines secreted by SSC. The vitamin D receptor (VDR) was visualized by immunofluorescence in SSC and by immunohistochemistry in the synovial tissues of three RA and three OA patients.

RESULTS

We detected intense staining for VDR in the synovial lining and vascular endothelium in tissue sections from all our RA and OA patients. Both 1,25(OH)₂D₃ and calcipotriol inhibited SSC proliferation for a prolonged time (up to 23 days with calcipotriol), but dexamethasone tended to increase SSC proliferation in a 4-day culture. 1,25(OH)₂D₃, calcipotriol and dexamethasone reduced the secretion of most inflammatory factors. Calcipotriol and dexamethasone additively reduced the secretions of IL-6, IFN-γ, basic FGF and VEGF in TNF-α stimulated SSC. The level of IL-6 was still diminished at 10 days after exposure, emphasizing the long-term impact of calcipotriol on SSC.

CONCLUSIONS

Exposure for 24-48h to 1,25(OH)₂D₃ or calcipotriol causes a long-lasting inhibition of cell proliferation and cytokine production in SSC in vitro.

Evidence that annexin II Is not a putative membrane receptor for 1?,25(OH)2-vitamin D3

The seco-steroid hormone 1alpha,25(OH)(2)-vitamin D(3) (1,25-D(3)) is known to generate biological responses via both genomic and non-genomic rapid signal transduction pathways. The calcium regulated annexin II/p11 heterotetramer (AII(2)/p11(2)] was proposed by Baran and co-authors to be the membrane receptor responsible for mediating non-genomic, rapid actions of 1,25-D(3), based on ligand affinity labeling, competition, and saturation analysis experiments. Given the cytosolic presence of both the monomeric and heterotetrameric form of AII and their functional regulation by intracellular calcium concentrations, which are known to be affected by 1,25-D(3) rapid, non-genomic activities, we investigated in vitro the affinity of [(3)H]1,25-D(3) for the AII monomer and AII(2)/p11(2) in the absence and presence of calcium using saturation analysis and gel-filtration chromatography. Using two different techniques for separating bound from free ligand (perchlorate and hydroxylapatite (HAP)) over a series of 30 experiments, no evidence for specific binding of [(3)H]1,25-D(3) was obtained with or without the presence of 700 nM exogenous calcium, using either the AII monomer or AII(2)/p11(2). However saturable binding of [(3)H]1,25-D(3) to the lipid raft/caveolae enriched rat intestinal fraction was consistently observed (K(d) = 3.0 nM; B(max) = 45 fmols/mg total protein). AII was detected in lipid raft/caveolae enriched fractions from rat and mouse intestine and ROS 17/2.8 and NB4 cells by Western blot, but incubation in the presence of exogenous calcium did not ablate 1,25-D(3) binding as reported by Baran et al. Our results suggest that AII does not bind 1,25-D(3) in a physiologically relevant manner; however, recent studies linking AII(2)/p11(2) phosphorylation to vesicle fusion and its calcium regulated localization may make AII a possible down-stream substrate for 1,25-D(3) induced rapid cellular effects.

Negative regulation of human parathyroid hormone gene promoter by vitamin D3 through nuclear factor Y

The negative regulation of the human parathyroid hormone (PTH) gene by biologically active vitamin D3 (1,25-dihydroxyvitamin D3; 1,25(OH)2D3) was studied in rat pituitary GH4C1 cells, which express factors needed for the negative regulation. We report here that NF-Y binds to sequences downstream of the site previously reported to bind the vitamin D receptor (VDR). Additional binding sites for NF-Y reside in the near vicinity and were shown to be important for full activity of the PTH gene promoter. VDR and NF-Y were shown to exhibit mutually exclusive binding to the VDRE region. According to our results, sequestration of binding partners for NF-Y by VDR also affects transcription through a NF-Y consensus binding element in GH4C1 but not in ROS17/2.8 cells. These results indicate that 1,25(OH)2D3 may affect transcription of the human PTH gene both by competitive binding of VDR and NF-Y, and by modulating transcriptional activity of NF-Y.

The validity of rheumatoid arthritis diagnoses in Finnish biobanks

OBJECTIVE

The aim of this study was to determine the validity of rheumatoid arthritis (RA) diagnoses in patients participating in Finnish biobanks.

METHOD

We reviewed the electronic medical records of 500 Finnish biobank participants: 125 patients with at least one visit with a diagnosis of seropositive RA, 125 patients with at least one visit with a diagnosis of seronegative RA, and 250 age- and gender-matched controls. The patients were chosen from five different biobank hospitals in Finland. A rheumatologist reviewed the medical records to assess whether each patients' diagnosis was correct. The diagnosis was compared with the diagnostic codes in the Finnish Care Register for Health Care (CRHC) and special reimbursement data of the Social Insurance Institution of Finland.

RESULTS

The positive predictive value (PPV) of CRHC diagnosis of RA (for seropositive and seronegative RA combined) was 0.82. For patients with a special reimbursement for anti-rheumatic medications for RA, the PPV was 0.89. The PPV was higher in patients with more than one visit. For one, two, five, and 10 visits, the PPV was 0.82, 0.85, 0.89, and 0.90, respectively, and for patients who also had the special reimbursement, the PPV was 0.89, 0.91, 0.93, and 0.94 for one, two, five, and 10 visits, respectively. In patients positive for anti-citrullinated protein antibodies, the PPV was 0.98.

CONCLUSION

These results demonstrate that the validity of RA diagnoses in Finnish biobanks was good and can be further improved by including data on special reimbursement for medication, number of visits, and serological data.

Differential synovial tissue expression of TLRs in seropositive and seronegative rheumatoid arthritis: A preliminary report

Toll-like receptors (TLRs) are known to have an important role in triggering the innate immune response and in priming antigen-specific adaptive immunity and inflammation. The differences in synovial tissue expression of the TLRs between seronegative and seropositive rheumatoid arthritis (RA) were examined from 9 seropositive RA, 5 seronegative RA and 4 osteoarthritis (OA) patients. Synovitis status was assessed using Krenn's scoring and TLR 1-9 expression by immunohistochemistry. Tissue citrulline content was analysed by HPLC method. In RA TLR expression was generally higher than in OA. TLR2 expression was higher in both seronegative and seropositive RA compared to OA. TLR 1, 4 and 8 expressions were higher in seropositive RA than in seronegative RA or in OA. For TLRs 3, 5, 6, 7 and 9 local differences of expression were found between groups. TLR 1-9 expression correlated with the synovitis grade. No statistical difference was found in synovial tissue citrulline content between the groups. In seropositive RA, the TLR repertoire in the synovial tissue differs from seronegative RA and could explain differences in disease outcomes. The high expression of protein sensing (TLR1, TLR2 and TLR4) and nucleic acid sensing TLRs (TLR7, TLR8 and TLR9) in the seropositive RA could make the synovium primed for reacting to citrullinated proteins and nucleic acids that could be released to extracellular space in formation of neutrophil extracellular traps. This reactivity could be augmented by Fc receptor activation by anti-citrullinated protein antibody immunocomplexes associated with seropositive RA.

Pharmacokinetics of intra-articular vitamin D analogue calcipotriol in sheep and metabolism in human synovial and mesenchymal stromal cells

Calcipotriol (MC903) is a side chain analogue of the biologically active 1,25-dihydroxyvitamin D₃ [1,25(OH)₂D₃]. Due to its anti-inflammatory and anti-proliferative effects on stromal cells, calcipotriol is a promising candidate for the local treatment of arthritis. In this preliminary work, we studied the pharmacokinetics and safety of calcipotriol after an IV (0.1 mg/kg given to one sheep) and intra-articular dose (0.054 mg/kg, 0.216 mg/kg and 0.560 mg/kg given to three sheep). The terminal half-life of calcipotriol was approximately 1 h after an IV dose. After intra-articular dosing, the systemic absorption was between 1 and 13% during the observed 24 h. Hypercalcemia or other clinical adverse effects did not occur in any animal during the study, and no macroscopic or microscopic alterations were seen in the synovium of the calcipotriol-injected knees compared to the vehicle knees. The in vitro metabolism of calcipotriol was analyzed with LC-MS from human synovial and mesenchymal stromal cell cultures. Both cell types were able to metabolize calcipotriol with MC1080 and MC1046 as the main metabolites. CYP24A1 transcripts were strongly induced by a 48-hour calcipotriol exposure in mesenchymal stromal cells, but not consistently in synovial stromal cells, as determined by RT-qPCR. Calcipotriol proved to be safe after a single intra-articular dose with applied concentrations, and it is metabolized by the cells of the joint. Slow dissolution of calcipotriol crystals in the joint can extend the pharmaceutical impact on the synovium, cartilage and subcortical bone.

Early vs. late enoxaparin for the prevention of venous thromboembolism in patients with ICH: A double blind placebo controlled multicenter study

BACKROUND

Venous thromboembolism (VTE) after primary intracerebral hemorrhage (ICH) worsens patient prognosis. Administering low-molecular weight heparins (LMWH) to prevent VTE early (24 h) may increase the risk of hematoma enlargement, whereas administering late (72 h) after onset may decrease its effect on VTE prevention. The authors investigated when it is safe and effective to start LMWH in ICH patients.

METHODS

In the setting of double blinded, placebo controlled randomization, patients >18 years of age with paretic lower extremity, and admitted to the emergency room within 12 h of the onset of ICH, were randomized into two groups. Patients in the enoxaparin group received 20 mg twice a day 24 h (early) after the onset of ICH and in the placebo group 72 h (late) after onset respectively. Both groups immediately received intermittent pneumatic compression stockings at the ER. Patients were prospectively and routinely screened for VTE and hemorrhagic complications 1 day after entering the study and again before discharge.

RESULTS

139 patients were included for randomization in this study. Only 3 patients developed VTE, 2 in the early enoxaparin group and one in the late enoxaparin group. No patients developed PE. Thromboembolic events (p = 0.901), risk of hematoma enlargement (p = 0.927) and overall outcome (P = 0.904) did not differ significantly between the groups.

CONCLUSION

Administering 40 mg/d LMWH for prevention of VTE to a spontaneous ICH patient is safe regardless of whether it is started 24 h (early) or 72 h (late) after the hemorrhage. Risk of hemorrhage enlargement is not associated with early LMWH treatment. Administering LMWH late did not increase VTEs.

Incidence of seropositive rheumatoid arthritis in population-based studies in Northern Savo, Finland, during 1980-2020

The objective is to evaluate the incidence of seropositive rheumatoid arthritis (RA) over 40-year period in Northern Savo, Finland. Data on new seropositive RA patients according to the American College of Rheumatology (ACR) 1987 classification criteria were collected in 2020-2021. In 2020 data on tobacco exposure, patient-reported dental health and living in residences with fluoridated tap water were gathered. Incidence rates were estimated and age- and gender-adjusted to Northern Savo population. The results were compared with data acquired in studies from 1980, 1990, 2000, and 2010. In 2020, 46 seropositive RA patients (21 females and 25 males) were recorded. The crude incidence of seropositive RA fulfilling the ACR 87 criteria in 2020 was 22.3 (95% CI 16.3 to 29.8)/100 000 and age and gender-adjusted 22.3 (95% CI 15.9 to 28.8)/100 000. Tobacco exposure > 5 pack years occurred 18% of females and 56% of males. Only 16% of males were full dentate. A total of 242 incident seropositive RA (age ≥ 16 years, 55% females) were identified in all study years. No differences in the gender-specific incidence rates in each cohort or in incidence between the studies every 10 years were recorded. The incidence of seropositive RA decreased in the age group < 55 years, p = 0.003. There was no change in the incidence of seropositive RA between genders or the study years. A declining trend for occurrence of seropositive RA in the young and early middle-aged population may reflect change in risk factors.

Cytokine data obtained from synovial stromal cells of patients with rheumatoid arthritis or osteoarthritis

In this article, we share the raw cytokine data obtained from basal and stimulated synovial stromal cells cultured from patients with rheumatoid arthritis or osteoarthritis. This data article is related to the research article entitled "1,25D₃ and calcipotriol, its hypocalcemic analog, exert a long-lasting anti-inflammatory and anti-proliferative effect in synoviocytes cultured from patients with rheumatoid arthritis and osteoarthritis (1). Cytokine levels were analyzed by a magnetic bead-based multiplex assay (a panel of 27 important cytokines) in two separate sets of experiments. The first was conducted with IL-1β and 1,25(OH)₂D₃ and the other with TNFα, calcipotriol, i.e. the hypocalcemic analog 1,25(OH)₂D₃, and dexamethasone. The raw data of this article display the individual variation in basal secretion of cytokines and in their response to different stimuli.

1,25(OH)2D3 and its analogue calcipotriol inhibit the migration of human synovial and mesenchymal stromal cells in a wound healing model - A comparison with glucocorticoids

Vitamin D analogue calcipotriol is currently used in the local treatment of psoriasis. However, it also has antiproliferative and anti-inflammatory effects in the cells of the joint - suggesting a possible benefit in local treatment of arthritis. In this study, calcipotriol was studied in different in vitro methods to find out its effect on synovial and mesenchymal stromal cells. Primary human cell lines of osteoarthritis or rheumatoid arthritis patients (five mesenchymal stromal cells, MSC, and four synovial stromal cells, SSC) were cultured to study migration and proliferation of the cells in a wound healing model. The media was supplemented with calcipotriol, 1,25(OH)2D3, dexamethasone, betamethasone, methylprednisolone or control solution in 1-100 nM concentrations. To see possible toxic effects of calcipotriol, concentrations up to 10 µM in SSCs and MSCs were studied in apoptosis and necrosis assays in four cell lines. Calcipotriol and 1,25(OH)2D3, as well as the three glucocorticoids, reduced the migration of both SSCs and MSCs. In SSCs, the effect of calcipotriol and 1,25(OH)2D3 was at least as effective as with glucocorticoids, while with MSCs, the glucocorticoids were stronger inhibitors of migration. The antimigratory of calcipotriol and 1,25(OH)2D3 was consistently maintained in 10 µM and 1 µM. Calcipotriol was not toxic to MSCs and SSCs up to concentrations of 10 µM. Calcipotriol, as well as 1,25(OH)2D3, exerts antimigratory and antiproliferative effects on human SSCs and MSCs of the joint. These effects are not caused by apoptosis or necrosis. Both calcipotriol and 1,25(OH)2D3 have similar effects as glucocorticoids without apparent toxicity, suggesting that calcipotriol might be an eligible candidate to the local treatment of arthritis with a broad therapeutic window.

The validity of systemic sclerosis diagnoses in two university hospitals in Finland

OBJECTIVE

This study aimed to determine the validity of systemic sclerosis (SSc) diagnoses in Finnish university hospitals.

METHOD

Electronic medical records for 385 patients with a registered diagnosis of SSc (ICD-10 code M34) in two Finnish university hospitals from 2008 to 2018 were reviewed to assess whether each patient's diagnosis was correct.

RESULTS

The positive predictive value (PPV) of a diagnosis of SSc was 0.66 when fulfilment of the 2013 American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) classification criteria for SSc was required; the PPV was 0.75 if patients meeting the 2001 LeRoy and Medsger classification criteria for early SSc were also included. When a diagnosis of SSc was made in a department of rheumatology, the PPV was 0.78, and 0.90 when including patients with early SSc. For the more specific diagnosis of limited cutaneous SSc (lcSSc), the PPV was 0.80, and 0.95 when including early SSc. For an lcSSc diagnosis made in rheumatology, the PPV was 0.81, and 0.97 with early SSc included.

CONCLUSION

These results demonstrate that in these two Finnish university hospitals, the diagnostic validity of a diagnosis of SSc was good if it was diagnosed in the department of rheumatology. For a more specific diagnosis of lcSSc, the most prevalent form of SSc in Finland, the validity was good even when registered in any department.

Intense symptoms of pain are associated with poor sleep, fibromyalgia, depression and sleep apnea in patients with rheumatoid arthritis and psoriatic arthritis. A register-based study

OBJECTIVES

To study whether poor sleep and comorbidities are associated with high symptom levels of patient-reported outcomes (PROs) pain, patient global assessment and fatigue in patients with rheumatoid arthritis (RA) and psoriatic arthritis (PsA), in a nation-wide cross-sectional setting.

METHODS

Clinical data were extracted from The Finnish Rheumatology Quality Register between 1.2021 and 9.2022. Self-reported sleep was categorized as "good" (little/no difficulties) or "poor" (great difficulties/can't) sleep. Data concerning comorbidities were collected from national registers. Descriptive statistics were used. Regression analyses were applied to analyze independent associations of sleep status, comorbidities and disease activity with pain in RA and PsA, adjusting for age and sex.

RESULTS

Among 13,512 patients with RA, 6052 [mean (SD) age 62 (13), 71% female] had sleep status reported; in PsA 1861/3636 [age 55 (13), 48% female]. In RA, 5072 (84%) reported good and 980 (16%) poor sleep; the corresponding numbers in PsA were 1460 (78%) and 401 (22%). Median values for objective disease activity were low and similar in patients with poor sleep and good sleep in both diseases. Among patients with no swollen joints, the median values for PROs were approximately three times higher for patients with poor sleep vs. good sleep in both diagnoses (P<0.001). In regression analyses, "poor" sleep was independently associated with higher symptoms in pain [B (95%CI) 20 (18,22) in RA and 23 (19, 26) in PsA], followed by comorbid fibromyalgia, as well as depression in RA and sleep apnea in PsA.

CONCLUSION

"Poor" sleep quality and comorbidities are independently associated with pain. Patient's sleep status is important to know especially in patients with severe symptoms without objective disease activity.

No adverse effects on periarticular tissue by intra-articular vitamin D analogue calcipotriol in a reduced-dose zymosan-induced arthritis model in rats

Calcipotriol, a vitamin D analogue, is an antiproliferative and anti-inflammatory drug currently used in psoriasis. Here, our aim was to analyse the safety of calcipotriol for cartilage and bone in alleviated-dose (0.1 mg instead of usual ≥1mg dose) zymosan-induced arthritis in rats. Theoretically, high doses of vitamin D or analogues could have detrimental effects on bone or cartilage. The rats were divided into four groups: vehicle (n = 9), dexamethasone 0.1 mg/kg (n = 9), calcipotriol 0.1 mg/kg (n = 8) and negative control (n = 10) with no injections. Arthritic rats were given phosphate-buffered saline (PBS) injections to left knees as a control. After euthanasia on day 8, all knees were imaged with micro-computed tomography for surface lesions and decalcified for histological analyses. Contrary to our expectations, no significant changes could be observed in the tomography data and histological scores among the three treatment groups or between the vehicle-treated and non-arthritic group. Calcipotriol did not cause adverse effects on cartilage or subchondral bone within a week, suggesting that it could be safely used in local treatment of arthritis. The alleviated model caused synovitis with local and systemic inflammatory response without cartilage erosions, which might be useful in studying self-limiting synovitis where cartilage or bone effects are not of primary interest.

Systemic sclerosis: changes in the incidence rates in the Finnish population during the years 1999-2018

OBJECTIVE

The aim of our study was to examine changes in the incidence of systemic sclerosis (SSc) in Finland using two different classification criteria.

METHOD

Medical records of patients who had been registered with ICD-10 code M34 from 1999 to 2018 in two university hospitals were reviewed retrospectively. This period was divided into 5 year periods: 1999-2003, 2004-2008, 2009-2013, and 2014-2018. Using American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) 2013 criteria and clinical findings, we reclassified patients into four groups: diffuse SSc, limited SSc, sine SSc, or early SSc. In the same population, we also investigated whether the ACR 1980 criteria were fulfilled.

RESULTS

In 1999-2018, 246 new patients with SSc and 45 patients with early SSc were identified using ACR/EULAR 2013 criteria. Of these patients, 70 fulfilled the ACR 1980 criteria. Using ACR/EULAR 2013 criteria, the increase in new diagnoses was statistically significant when comparing the fourth period with the first period (p = 0.0012). The increase was due to a rise in limited SSc. Mean annual incidence rates in these groups were 0.9, 1.2, 1.9, and 2.8 per 100 000 inhabitants ≥ 16 years old. An increasing trend was also seen when using ACR 1980 criteria, but this was not statistically significant.

CONCLUSION

The incidence of SSc increased during the period between 1999-2003 and 2014-2018 using ACR/EULAR 2013, but not using ACR 1980 criteria. The increase was detected within a limited SSc subclass, owing to more sensitive classification criteria.

Disease burden measured by patient-reported outcomes: does psoriatic arthritis feel worse than rheumatoid arthritis? A cross-sectional nationwide study

OBJECTIVES

To study the subjective disease burden of patients with psoriatic arthritis (PsA) and rheumatoid arthritis (RA), using patient-reported outcomes (PROs) cross-sectionally.

METHODS

Data of 3598 patients with PsA and 13913 with RA were extracted from the database. Measures included the VAS-values of pain, fatigue and patient global assessment (PGA), HAQ, and disease activity at the most recent visit/remote contact in the period 1.2020 to 9.2021. Values were compared between patients with PsA and RA overall, and by sex and age (<50, 50-59, 60-69 and ≥70 years). Regression analyses were applied.

RESULTS

The overall median (IQR)-values for pain were 29 (10, 56) for PsA and 26 (10, 51) for RA, 29 (9, 60) and 28 (8, 54) for fatigue, 28 (10, 52) and 29 (11, 51) for PGA, 0.4 (0, 0.9) and 0.5 (0, 1.0) for HAQ (p<0.001 for all comparisons; adjusted for sex and age). The median (IQR)-values for pain, fatigue, PGA and HAQ were higher for PsA vs. RA in most age groups for males and females. All PROs were higher in older patients with both diagnoses. The median values for DAS28, doctor global assessment, ESR and CRP were 1.9 vs. 2.0, 8 vs. 8, 7 vs. 8 and 2 vs. 3 in PsA and RA, respectively.

CONCLUSIONS

Overall, both PsA and RA groups showed moderate disease control by patients' perspective, but the burden of disease was higher especially in women with PsA compared to RA. Disease activity was similar and low in both diseases.

Handling of missing component information for common composite score outcomes used in axial spondyloarthritis research when complete-case analysis is unbiased

BACKGROUND

Observational data on composite scores often comes with missing component information. When a complete-case (CC) analysis of composite scores is unbiased, preferable approaches of dealing with missing component information should also be unbiased and provide a more precise estimate. We assessed the performance of several methods compared to CC analysis in estimating the means of common composite scores used in axial spondyloarthritis research.

METHODS

Individual mean imputation (IMI), the modified formula method (MF), overall mean imputation (OMI), and multiple imputation of missing component values (MI) were assessed either analytically or by means of simulations from available data collected across Europe. Their performance in estimating the means of the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), the Bath Ankylosing Spondylitis Functional Index (BASFI), and the Ankylosing Spondylitis Disease Activity Score based on C-reactive protein (ASDAS-CRP) in cases where component information was set missing completely at random was compared to the CC approach based on bias, variance, and coverage.

RESULTS

Like the MF method, IMI uses a modified formula for observations with missing components resulting in modified composite scores. In the case of an unbiased CC approach, these two methods yielded representative samples of the distribution arising from a mixture of the original and modified composite scores, which, however, could not be considered the same as the distribution of the original score. The IMI and MF method are, thus, intrinsically biased. OMI provided an unbiased mean but displayed a complex dependence structure among observations that, if not accounted for, resulted in severe coverage issues. MI improved precision compared to CC and gave unbiased means and proper coverage as long as the extent of missingness was not too large.

CONCLUSIONS

MI of missing component values was the only method found successful in retaining CC's unbiasedness and in providing increased precision for estimating the means of BASDAI, BASFI, and ASDAS-CRP. However, since MI is susceptible to incorrect implementation and its performance may become questionable with increasing missingness, we consider the implementation of an error-free CC approach a valid and valuable option.

TRIAL REGISTRATION

Not applicable as study uses data from patient registries.

Similar levels of disease activity and remission rates in patients with psoriatic arthritis and rheumatoid arthritis-results from the Finnish quality register

OBJECTIVES

To compare the current disease activity and remission rates, and their regional variation in patients with psoriatic arthritis (PsA) and rheumatoid arthritis (RA) in Finland.

METHODS

Data of patients' most recent visit in 1/2020-9/2021 were extracted from the Finnish Rheumatology Quality Register. Measures for disease activity and remission included joint counts, DAS28, cDAPSA, CDAI, the Boolean definition, and physician assessment. Regression analyses were applied, adjusted for age and sex.

RESULTS

Data of 3598 patients with PsA (51% female, mean age 54 years) and 13,913 patients with RA (72% female, 74% ACPA-positive, mean age 62 years) were included. The median (IQR) DAS28 was 1.9 (1.4, 2.6) in PsA and 2.0 (1.6, 2.7) in RA (p = 0.94); for cDAPSA, the median (IQR) values were 7.7 (3.1, 14) in PsA and 7.7 (3.3, 14) in RA (p < 0.001). In all regions in both diseases, the median DAS28 was ≤ 2.6 and the median cDAPSA < 13. Remission rates included DAS28 < 2.6 in 73% in PsA and 69% in RA (p = 0.17) and Boolean remission in 17% in PsA and 15% in RA (p < 0.001). By other definitions of remission, the rates ranged between 30% and 46%. Methotrexate was currently used by 49% in PsA and 57% in RA (p < 0.001). Self-administered bDMARDs were currently used by 37% in PsA and 21% in RA (p < 0.001).

CONCLUSION

The overall disease activity was low and similar in patients with PsA and RA across the country. Remission rates varied between 15 and 73%, depending on the definition but were similar in PsA and RA. Key Points • The disease activity and clinical picture was similar between patients with PsA and RA, in a cross-sectional setting in 1.2020-9.2021. • A significant majority of patients with PsA had low disease activity or were in remission according to cDAPSA. Majority of patients with RA were in remission according to DAS28. • Patients with PsA and RA used methotrexate similarly. The utilization of bDMARDs was more prevalent in patients with PsA.

The feasibility of existing JADAS10 cut-off values in clinical practice: a study of data from The Finnish Rheumatology Quality Register

BACKGROUND

The ten-joint juvenile arthritis disease activity score (JADAS10) is designed to measure the level of disease activity in non-systemic juvenile idiopathic arthritis by providing a single numeric score. The clinical JADAS10 (cJADAS10) is a modification of the JADAS10 that excludes erythrocyte sedimentation rate (ESR). Three different sets of JADAS10/cJADAS10 cut-offs for disease activity states have been published, i.e., the Backström, Consolaro, and Trincianti cut-offs. The objective of this study was to investigate the performance of existing JADAS10 cut-offs in real-life settings using patient data from The Finnish Rheumatology Quality Register (FinRheuma).

METHODS

Data were collected from the FinRheuma register. The proportion of patients with an active joint count (AJC) above zero when classified as being in clinically inactive disease (CID) or low disease activity (LDA) groups according to existing JADAS10/cJADAS10 cut-off levels were analyzed.

RESULTS

A significantly larger proportion of the patients classified as being in CID had an AJC > 0 when using the JADAS10/cJADAS10 cut-offs by Trincianti et al. compared to those for the other cut-offs. In the LDA group, a significantly larger proportion of the polyarticular patients (35%/29%) had an AJC of two when Trincianti JADAS10/cJADAS10 cut-offs were used compared with when Backström (11%/10%) and Consolaro (7%/3%) JADAS10/cJADAS10 cut-offs were used.

CONCLUSIONS

We found the cut-offs proposed by Consolaro et al. to be the most feasible, since these cut-off levels for CID do not result in the misclassification of active disease as remission, and the proportion of patients with AJC > 1 in the LDA group is lowest using these cut-offs.

A single intra-articular dose of vitamin D analog calcipotriol alleviates synovitis without adverse effects in rats

1,25-dihydroxyvitamin-D3 and its derivatives have shown anti-arthritic and chondroprotective effects in experimental animal models with prophylactic dosing. The purpose of this preliminary study was to test the efficacy and safety of calcipotriol, vitamin D analog, as a treatment for a fully-developed knee arthritis in Zymosan-induced arthritis (ZIA) model. Forty 5-month-old male Sprague-Dawley rats were randomized into three arthritis groups and a non-arthritic control group with no injections (10 rats/group). A day after Zymosan (0.1 mg) had been administrated into the right knee joints, the same knees were injected with calcipotriol (0.1 mg/kg), dexamethasone (0.1 mg/kg) or vehicle in a 100 μl volume. The left control knees were injected with saline (PBS) on two consecutive days. All injections, blood sampling and measurements were performed under general anesthesia on days 0, 1, 3 and 8. Internal organs and knees were harvested on day 8 and the histology of the whole knees was assessed blinded. Joints treated with calcipotriol showed a milder histological synovitis than those treated with vehicle (p = 0.041), but there was no statistically significant difference between the dexamethasone and vehicle groups. The clinical severity of arthritis did not differ between the arthritis groups measured by body temperature, swelling of the knee, thermal imaging, clinical scoring or cytokine levels on days 1, 3 and 8. Weight loss was bigger in rats treated with dexamethasone, propably due to loss of appetite,compared to other arthritis groups on days 2-3 (p<0.05). Study drugs did not influence serum calcium ion and glucose levels. Taken together, this preliminary study shows that a single intra-articular injection of calcipotriol reduces histological grade of synovitis a week after the local injection, but dexamethasone did not differ from the vehicle. Calcipotriol may have an early disease-modifying effect in the rat ZIA model without obvious side effects.

Causes and predictors of death among Finnish patients with systemic sclerosis

OBJECTIVE

The aim of this study was to assess causes and predictors of death among Finnish patients with systemic sclerosis (SSc).

METHOD

Medical records of patients registered with the ICD-10 code M34 from 1996 to 2018 in two university hospitals were reviewed retrospectively. Clinical data were collected until the end of 2020. Death certificates were obtained from Statistics Finland up to August 2021. Using death certificates and patient records, the cause of death for each patient was determined. The mean age at death, median time from SSc diagnosis, and factors predicting death were analysed.

RESULTS

Among 313 SSc patients, 91 deaths occurred between April 2000 and September 2020. Overall 5 and 10 year survival rates were 88.4% and 80.2%, respectively. SSc was the most common primary cause of death (n = 35) and interstitial lung disease (ILD) was the most common SSc-related cause of death (n = 13). Moreover, 52% of the patients with diffuse SSc and 33% of those with limited cutaneous SSc died as a result of SSc itself. Patients who died because of SSc were significantly younger [mean ± sd age 65.6 ± 12.7 years, 95% confidence interval (CI) 61.2-70.1] than those who died from other causes (74.2 ± 9.6 years, 95% CI 71.5-76.9) (p = 0.0006). ILD, pulmonary arterial hypertension, gastrointestinal involvement, male gender, and older age at disease onset predicted death.

CONCLUSION

The disease itself was the major cause of death among Finnish SSc patients, in both diffuse and limited forms of SSc.

Initial presentation of early rheumatoid arthritis

OBJECTIVES

To study the joint distribution and clinical picture of rheumatoid arthritis (RA) at the initial presentation in seropositive (anti-citrullinated protein antibody (ACPA) and/or rheumatoid factor (RF) positive) and negative patients and the effect of duration of symptoms on the clinical picture.

METHODS

Data of patients who received reimbursement for DMARDs for newly diagnosed RA in 1/2019 to 9/2021 were extracted from the national databases. Joint counts, presence of symmetrical swelling, other disease activity measures, and patient reported outcomes (PROs) were compared in seropositive and negative patients. Regression analyses were applied to compare clinical variables in patients with duration of symptoms of <3, 3-6, and >6 months, adjusted for age, sex, and seropositivity.

RESULTS

Data of 1816 ACPA and RF-tested patients were included. Symmetrical swelling was present in 75% of patients. Seronegative versus positive patients had higher value for all disease activity measures and PROs including median swollen joint count (SJC46 10 versus 5) and DAS28 (4.7 versus 3.7), (p<0.001). Patients diagnosed in <3 months had higher median pain VAS (62 versus 52 and 50, p<0.001) and HAQ (1.1 versus 0.9 and 0.75, p = 0.002) compared to those with a duration of symptoms of 3-6 and >6 months. Patients diagnosed >6 months were ACPA-positive more frequently (77% versus 70% in other groups, p = 0.045).

CONCLUSION

Incident RA presents mainly as symmetric arthritis. Seronegative patients have higher disease burden at the initial presentation. Patients experiencing more severe pain and decreased functional ability are diagnosed earlier, regardless of ACPA- status.