Risk of liver fibrosis associated with long-term methotrexate therapy may be overestimated.

BACKGROUND & AIMS: The risk of significant liver fibrosis from prolonged methotrexate (MTX) exposure has been estimated at around 5%, prompting intensive monitoring strategies. However, the evidence is derived from retrospective studies that under-reported risk factors for liver disease. We evaluated the risk of long-term MTX therapy on liver fibrosis in a longitudinal cohort study using two non-invasive markers. METHOD: Between 2014-2021, adult patients diagnosed with rheumatoid arthritis (RA) or psoriasis for ≥2 years were recruited prospectively from six UK sites. The MTX group included patients who received MTX for ≥6 months, whereas the unexposed group included those who never received MTX. All patients underwent full liver profiling, with transient elastography (TE) and enhanced liver fibrosis (ELF) marker measurements. RESULTS: A total of 999 patients (mean age 60.8 ± 12 years, 62.3% females) were included. Of 976 with valid TE values, 149 (15.3%) had liver stiffness ≥7.9 kPa. Of 892 with a valid ELF, 262 (29.4%) had ELF ≥9.8. Age and BMI were independently associated with elevated liver stiffness and ELF. Neither MTX cumulative dose nor duration was associated with elevated liver stiffness. Diabetes was the most significant risk factor associated with liver stiffness ≥7.9 kPa (adjusted odds ratio = 3.19; 95% CI 1.95-5.20; p <0.001). Regular use of non-steroidal anti-inflammatory drugs showed the strongest association with ELF ≥9.8 (odds ratio = 1.76; 95% CI 1.20-2.56; p = 0.003), suggesting the degree of joint inflammation in RA may confound ELF as a non-invasive marker of liver fibrosis. CONCLUSION: The risk of liver fibrosis attributed to MTX itself might have been previously overestimated; there is a need to consider modifying current monitoring guidelines for MTX. IMPACT AND IMPLICATIONS: Current guidelines recommend intensive (2-3 monthly) monitoring strategies for patients on long-term methotrexate therapy due to the potential risk of liver fibrosis. Evaluation of the association using two validated non-invasive markers of liver fibrosis, liver stiffness and enhanced liver fibrosis score, in a large cohort of patients with rheumatoid arthritis or psoriasis shows that the reported risk has previously been overestimated. The clinical focus should be to improve patients' metabolic risk factors, diabetes and BMI, that are independently associated with liver stiffness. There is a need to consider modifying current treatment monitoring guidelines for methotrexate.

YAP and TAZ Promote Periosteal Osteoblast Precursor Expansion and Differentiation for Fracture Repair.

In response to bone fracture, periosteal progenitor cells proliferate, expand, and differentiate to form cartilage and bone in the fracture callus. These cellular functions require the coordinated activation of multiple transcriptional programs, and the transcriptional regulators Yes-associated protein (YAP) and transcriptional co-activator with PDZ-binding motif (TAZ) regulate osteochondroprogenitor activation during endochondral bone development. However, recent observations raise important distinctions between the signaling mechanisms used to control bone morphogenesis and repair. Here, we tested the hypothesis that YAP and TAZ regulate osteochondroprogenitor activation during endochondral bone fracture healing in mice. Constitutive YAP and/or TAZ deletion from Osterix-expressing cells impaired both cartilage callus formation and subsequent mineralization. However, this could be explained either by direct defects in osteochondroprogenitor differentiation after fracture or by developmental deficiencies in the progenitor cell pool before fracture. Consistent with the second possibility, we found that developmental YAP/TAZ deletion produced long bones with impaired periosteal thickness and cellularity. Therefore, to remove the contributions of developmental history, we next generated adult onset-inducible knockout mice (using Osx-CretetOff ) in which YAP and TAZ were deleted before fracture but after normal development. Adult onset-induced YAP/TAZ deletion had no effect on cartilaginous callus formation but impaired bone formation at 14 days post-fracture (dpf). Earlier, at 4 dpf, adult onset-induced YAP/TAZ deletion impaired the proliferation and expansion of osteoblast precursor cells located in the shoulder of the callus. Further, activated periosteal cells isolated from this region at 4 dpf exhibited impaired osteogenic differentiation in vitro upon YAP/TAZ deletion. Finally, confirming the effects on osteoblast function in vivo, adult onset-induced YAP/TAZ deletion impaired bone formation in the callus shoulder at 7 dpf before the initiation of endochondral ossification. Together, these data show that YAP and TAZ promote the expansion and differentiation of periosteal osteoblast precursors to accelerate bone fracture healing. © 2020 American Society for Bone and Mineral Research (ASBMR).

YAP and TAZ Mediate Osteocyte Perilacunar/Canalicular Remodeling.

Bone fragility fractures are caused by low bone mass or impaired bone quality. Osteoblast/osteoclast coordination determines bone mass, but the factors that control bone quality are poorly understood. Osteocytes regulate osteoblast and osteoclast activity on bone surfaces but can also directly reorganize the bone matrix to improve bone quality through perilacunar/canalicular remodeling; however, the molecular mechanisms remain unclear. We previously found that deleting the transcriptional regulators Yes-associated protein (YAP) and transcriptional co-activator with PDZ-motif (TAZ) from osteoblast-lineage cells caused lethality in mice due to skeletal fragility. Here, we tested the hypothesis that YAP and TAZ regulate osteocyte-mediated bone remodeling by conditional ablation of both YAP and TAZ from mouse osteocytes using 8 kb-DMP1-Cre. Osteocyte-conditional YAP/TAZ deletion reduced bone mass and dysregulated matrix collagen content and organization, which together decreased bone mechanical properties. Further, YAP/TAZ deletion impaired osteocyte perilacunar/canalicular remodeling by reducing canalicular network density, length, and branching, as well as perilacunar flourochrome-labeled mineral deposition. Consistent with recent studies identifying TGF-ß as a key inducer of osteocyte expression of matrix-remodeling enzymes, YAP/TAZ deletion in vivo decreased osteocyte expression of matrix proteases MMP13, MMP14, and CTSK. In vitro, pharmacologic inhibition of YAP/TAZ transcriptional activity in osteocyte-like cells abrogated TGF-ß-induced matrix protease gene expression. Together, these data show that YAP and TAZ control bone matrix accrual, organization, and mechanical properties by regulating osteocyte-mediated bone remodeling. Elucidating the signaling pathways that control perilacunar/canalicular remodeling may enable future therapeutic targeting of bone quality to reverse skeletal fragility. © 2019 American Society for Bone and Mineral Research.

Use of febuxostat in the management of gout in the United Kingdom.

Gout is the most common cause of inflammatory arthritis worldwide. Despite clinical cure being achievable and multiple evidence-based guidelines having been published, the incidence and prevalence continues to increase and the condition remains undertreated. Concerns regarding allopurinol have limited its use in those with renal impairment. Febuxostat, a novel xanthine oxidase inhibitor requiring no dose adjustment in mild-moderate renal impairment was launched in the United Kingdom (UK) in 2010. We review published data on the efficacy, safety and tolerability of febuxostat and provide an opinion on its place in the management of gout in the UK in the context of other published guidelines. One phase II trial, multiple phase III trials [febuxostat versus allopurinol controlled trial (FACT), APEX, CONFIRMS] and two open-label extension trials have demonstrated febuxostat given at the doses commonly used in UK practice (80 mg, 120 mg) to reduce serum urate more effectively than those receiving fixed-dose allopurinol. Overall adverse event rates were comparable across treatment groups aside from gout flare (more common in febuxostat-treated patients) and concerns regarding cardiovascular toxicity are being further evaluated in two large trials. If the outcomes of these are favourable, we would anticipate a marked increase in the use of febuxostat in the UK market. We would advocate the use of febuxostat to target a serum urate < 0.3 mmol/l (5 mg/dl) as a second-line urate-lowering therapy in patients with hyperuricaemia, and clinical gout in those intolerant of allopurinol, or in those in whose renal function precludes optimal dose escalation to achieve target serum urate. We would advise prophylaxis against gouty flare with colchicine, nonsteroidal anti-inflammatory drugs (NSAIDs), or Cyclo-oxygenase-2 selective NSAID (COXIB) after febuxostat initiation.

Up-to-date management of gout.

PURPOSE OF REVIEW: Gout is a true crystal deposition disease, extremely painful and bone and tissue damaging if untreated. It is the only curable form of arthritis. Although we have many treatments to cure gout, it is a disease that is consistently undertreated/mismanaged and perceived by clinicians and the lay public as a 'laughable condition' with the patients' lifestyle often held erroneously to account. This article would give you a good understanding of modern and established pharmacological and nonpharmacological treatments used in the management of acute and chronic gout and how to 'treat to target' to cure the disease. RECENT FINDINGS: Many of the drugs we use to manage patients with gouty arthritis have been in existence since the 1970s and 1980s. In the past few years, because of the improved physiological understanding of gout, new innovative treatments such as anti-IL inhibitors, a nonxanthine oxidase inhibitor and the uricase enzymes have been developed adding to our armamentarium of drugs. SUMMARY: With the introduction of new research, we have been able to explore how to also use established treatments more effectively, raising the profile of gout and its best management and introducing the principle of treating the patient to urate target.

The modern management of gout.

Gout is an inflammatory arthritis characterized by self-limiting but excruciatingly painful acute attacks. These are a consequence of monosodium urate (MSU) crystals being deposited within articular or periarticular tissue. Chronic tophaceous gout can develop after years of acute intermittent gout. Recent discoveries, including the role of the inflammasome and intracellular events demonstrating that pro-inflammatory cytokines, IL-1 beta, -8 and TNF-alpha, promote neutrophil influx. Also, genetic advances with the identification of the URAT-1 transporter and genetic variation in SLC 2A9 as a key regulator of urate homoeostasis, have given us deeper understanding of the pathophysiology of gout, and also allow for more targeted treatments. Hopefully, new and emerging therapeutic options will reduce treatment-resistant gout in patients who are unresponsive or unable to take traditional urate lowering therapy. The development of new therapies may also increase patient numbers being treated in the specialist setting, which may have several secondary benefits.

Evidence-based clinical guidelines: a new system to better determine true strength of recommendation.

RATIONALE, AIMS AND OBJECTIVES: Clinical practice guidelines often grade the 'strength' of their recommendations according to the robustness of the supporting research evidence. The existing methodology does not allow the strength of recommendation (SOR) to be upgraded for recommendations for which randomized controlled trials are impractical or unethical. The purpose of this study was to develop a new method of determining SOR, incorporating both research evidence and expert opinion. METHODS: A Delphi technique was employed to produce 10 recommendations for the role of exercise therapy in the management of osteoarthritis of the hip or knee. The SOR for each recommendation was determined by the traditional method, closely linked to the category of research evidence found on a systematic literature search, and on a visual analogue scale (VAS). Recommendations were grouped A-D according to the traditional SOR allocated and the mean VAS calculated. Difference across the groups was assessed by one-way ANOVA variance analysis. RESULTS: Mean VAS scores for the traditional SOR groups A-D and one proposition which was 'not recommended' showed significant linearity on one-way ANOVA. However, certain recommendations which, for practical reasons, could not assessed in randomized controlled trials and therefore could not be recommended strongly by the traditional methodology, were allocated a strong recommendation by VAS. CONCLUSIONS: This new system of grading strength of SOR is less constrained than the traditional methodology and offers the advantage of allowing SOR for procedures which cannot be assessed in RCTs for practical or ethical reasons to be upgraded according to expert opinion.

Birthweight, vitamin D receptor gene polymorphism, and risk of lumbar spine osteoarthritis.

OBJECTIVE: To investigate risk factors for adult lumbar spine osteoarthritis (OA) including polymorphisms of the vitamin D receptor gene (VDR) and birthweight. METHODS: Plain radiographs of the lumbar spine were taken in 392 healthy subjects and graded for osteophytes and disc space narrowing (DSN); demographic data were collected. Details of birthweight and weight at 1 year were retrieved from historical records. VDR gene allelic variation was analyzed in 291 subjects. RESULTS: The mean age of the cohort was 65.8 years; mean weight was 68.9 kg in women and 80.1 kg and men. Osteophytes of grade >/= 2 were found in 63.5% of this cohort; DSN >/= 2 was present in 14.3% of subjects. Increasing osteophyte severity was significantly associated with age, adult weight, and manual social class; DSN was not. Presence and severity of osteophytes were associated with low birthweight and lower weight at 1 year in men, but not in women. No associations were found for DSN. The B allele of the VDR gene was associated with increasing severity of osteophyte. There was a significant interaction between birthweight and VDR gene in determining risk of osteophytosis in men (p for interaction = 0.04). The VDR-birthweight interaction pattern was similar but not statistically significant in women. CONCLUSION: Lumbar spine OA was a prevalent finding in this cohort. Both birthweight and polymorphisms in the VDR gene were associated with the presence of lumbar spine osteophytes and a significant interaction was observed between these 2 factors in men.

Systemic vasculitis.

The systemic vasculitides are a heterogeneous group of disorders characterized by inflammation of blood vessel walls. They can be classified according to the size of vessel affected and also into primary de novo vasculitides and secondary to other disease processes. Treatments differ and overlap depending on the type of vasculitis. It is therefore important to make the correct diagnosis and treat appropriately to achieve remission as there is a substantial mortality implication.