Project description:Urate in the fingernails of gout patients and healthy volunteers was successfully detected by high-performance liquid chromatography (HPLC) with ultraviolet (UV) in our previous research. This study aimed to further investigate whether nail urate could be a proxy for the burden of monosodium urate (MSU) crystals deposits in gout. To this end, we conducted a study in two parts. Firstly, we successfully detected urate in the nail by HPLC-UV and evaluated nail urate concentrations in control subjects and patients with gout. As expected, we found that levels of nail urate were significantly higher in patients with gout than in healthy controls, and the nail urate level was significantly correlated with the volume of MSU crystals deposits measured by dual-energy CT (DECT). Secondly, we found that nail urate can reflect changes in urate levels in the body during urate lowering therapy through a 3-month follow-up study. Our results provide the possibility of quantification of urate in human fingernails as a non-invasive alternative for assessing MSU crystals deposits in gout.
Project description:ImportanceApproximately 12 million adults in the US have a history of gout, but whether serum urate levels can help predict recurrence is unclear.ObjectiveTo assess associations of a single serum urate measurement with subsequent risk of acute gout flares and subsequent risk of hospitalizations for gout among patients in the UK with a history of gout.Design, setting, and participantsThis retrospective study included patients with a history of gout identified from the UK between 2006 and 2010 who were followed up through Primary Care Linked Data medical record linkage until 2017 and through the Hospital Episode Statistics database until 2020.ExposuresSerum urate levels at enrollment.Main outcome and measureRate of recurrent acute gout, ascertained by hospitalization, outpatient, and prescription/procedure records, and adjusted rate ratios using negative binomial regressions.ResultsAmong 3613 patients with gout (mean age, 60 years; 3104 [86%] men), 1773 gout flares occurred over a mean follow-up of 8.3 years. Of these, 1679 acute gout flares (95%) occurred in people with baseline serum urate greater than or equal to 6 mg/dL and 1731 (98%) occurred in people with baseline serum urate greater than or equal to 5 mg/dL. Rates of acute gout flares per 1000 person-years were 10.6 for participants with baseline urate levels less than 6 mg/dL, 40.1 for levels of 6.0 to 6.9 mg/dL, 82.0 for levels of 7.0 to 7.9 mg/dL, 101.3 for levels of 8.0 to 8.9 mg/dL, 125.3 for urate levels of 9.0 to 9.9 mg/dL, and 132.8 for levels greater than or equal to 10 mg/dL. Rate ratio of flares were 1.0, 3.37, 6.93, 8.67, 10.81, and 11.42, respectively, over 10 years (1.61 [1.54-1.68] per mg/dL). Rates of hospitalization per 1000 person-years during follow-up were 0.18 for those with baseline serum urate less than 6 mg/dL, 0.97 for serum urate of 6.0 to 6.9 mg/dL, 1.8 for serum urate of 7.0 to 7.9 mg/dL, 2.2 for serum urate of 8.0 to 8.9 mg/dL, 6.7 for serum urate of 9.0 to 9.9 mg/dL, and 9.7 for serum urate greater than or equal to 10 mg/dL. Rate ratios of hospitalization for gout, adjusting for age, sex, and race were 1.0, 4.70, 8.94, 10.37, 33.92, and 45.29, respectively (1.87 [1.57-2.23] per mg/dL).Conclusions and relevanceIn this retrospective study of patients with a history of gout, serum urate levels at baseline were associated with the risk of subsequent gout flares and rates of hospitalization for recurrent gout. These findings support using a baseline serum urate level to assess risk of recurrent gout over nearly 10 years of follow-up.
Project description:ObjectiveSeveral plausible mechanisms and anecdotal descriptions suggest that gout attacks often occur at night, although there are no scientific data supporting this. We undertook this study to evaluate the hypothesis that gout attacks occur more frequently at night.MethodsWe conducted a case-crossover study to examine the risk of acute gout attacks in relation to the time of the day. Gout patients were prospectively recruited and followed up via the internet for 1 year. Participants were asked about the following information concerning their gout attacks: the date and hour of attack onset, symptoms and signs, medication use, and purported risk factors during the 24- and 48-hour periods prior to the gout attack. We calculated the odds ratios (ORs) of gout attacks (with 95% confidence intervals [95% CIs]) according to three 8-hour time blocks of the day (i.e., 12:00 AM to 7:59 AM, 8:00 AM to 3:59 PM [reference], and 4:00 PM to 11:59 PM) using conditional logistic regression.ResultsOur study included 724 gout patients who experienced a total of 1,433 attacks (733, 310, and 390 attacks during the first, second, and third 8-hour time blocks, respectively) over 1 year. The risk of gout flares in the 8-hour overnight time block (12:00 AM to 7:59 AM) was 2.36 times higher than in the daytime (8:00 AM to 3:59 PM) (OR 2.36 [95% CI 2.05-2.73]). The corresponding OR in the evening (4:00 PM to 11:59 PM) was 1.26 (95% CI 1.07-1.48). These associations persisted among those with no alcohol use and in the lowest quintile of purine intake in the 24 hours prior to attack onset. Furthermore, these associations persisted in subgroups according to sex, age group, obesity status, diuretic use, and use of allopurinol, colchicine, and nonsteroidal antiinflammatory drugs.ConclusionThese findings provide the first prospective evidence that the risk of gout attacks during the night and early morning is 2.4 times higher than in the daytime. Further, these data support the purported mechanisms and historical descriptions of the nocturnal onset of gout attacks and may have implications for antigout prophylactic measures.
Project description:Crystallization of monosodium urate monohydrate (MSU) leads to painful gouty arthritis. Despite extensive research it is still unknown how this pathological biomineralization occurs, which hampers its prevention. Here we show how inflammatory MSU crystals form after a non-inflammatory amorphous precursor (AMSU) that nucleates heterogeneously on collagen fibrils from damaged articular cartilage of gout patients. This non-classical crystallization route imprints a nanogranular structure to biogenic acicular MSU crystals, which have smaller unit cell volume, lower microstrain, and higher crystallinity than synthetic MSU. These distinctive biosignatures are consistent with the template-promoted crystallization of biotic MSU crystals after AMSU at low supersaturation, and their slow growth over long periods of time (possibly years) in hyperuricemic gout patients. Our results help to better understand gout pathophysiology, underline the role of cartilage damage in promoting MSU crystallization, and suggest that there is a time-window to treat potential gouty patients before a critical amount of MSU has slowly formed as to trigger a gout flare.
Project description:As a prominent feature of gout, monosodium urate (MSU) crystal deposition can induce gout flare, yet its impact on blood immune in gout remission patients still remains unclear. In this study, single-cell RNA sequencing (scRNA-seq) is used to compare the gene expression profiling of peripheral blood mononuclear cells (PBMCs) among intercritical gout remission patients, advanced gout remission patients and healthy volunteers. The increase of HLA-DQA1high classical monocytes, and their important role in immune inflammatory responses and osteoclast differentiation are discovered in advanced gout remission patients. Moreover, the differentiation level of CD8+T cells are found to elevate in advanced gout remission patients, which is further validated via flow cytometry. It is also observed that pathways related to bone metabolism and inflammatory responses are overactive in advanced gout remission patients. By analysis on intercellular communication network, immune-related cell-cell interactions among PBMCs are shown to enhance in both intercritical and advanced gout remission patients. The analyses on gene expression and LC-MS/MS together indicate the increased metabolic level of arachidonic acid in gout remission patients with MSU deposition at the intercritical and advanced stage. The study reveals distinctive blood immune characteristics in gout remission with MSU deposition, which provides more sights into its pathogenesis.
Project description:BackgroundThis study aimed to explore the clinical characteristics of perioperative acute gout attacks in patients with varying uric acid levels undergoing orthopedic surgery, identify the risk factors for gout recurrence within the first postoperative year, and provide a disease prevention and diagnostic reference.MethodsThis hospital-based retrospective study was conducted between January 2018 and December 2020. According to the blood uric acid levels at admission, the patients were grouped into either the normal uric acid level group or the hyperuricemia group. Patient comorbidities, serum uric acid levels, inflammatory indicators, follow-up recurrence rates, and other indicators were compared.ResultThe uric acid decline ratio and the inflammatory indexes (white blood cell count and C-reactive protein level) at the time of the attack were significantly higher in the normal uric acid level group than in the hyperuricemia group (P < 0.05). Patients in the hyperuricemia group with diabetes and tophi and those administered diuretics were more prone to acute gout attacks than those in the normal uric acid level group (P < 0.05). In the normal uric acid level group, 22 patients (84.6%) exhibited single joint involvement, whereas only 18 patients (47.4%) in the hyperuricemia group demonstrated single joint involvement (P < 0.05). After 1 year of follow-up, the gout recurrence rate in the hyperuricemia group was 44.7%, which was significantly higher that the recurrence rate in the normoglycemic group (11.5%; P < 0.05). Presenting tophi in perioperative orthopedic surgery patients was found to be an independent risk factor for gout recurrence within 1 year (RR = 4.80; P = 0.029).ConclusionThe recurrence rate of gout in patients with hyperuricemia during perioperative period increased 1 year after operation. Therefore, it is crucial to monitor the uric acid level to prevent acute gout attacks during the perioperative period and recurrence during the 1-year follow-up period. Moreover, the risk of an acute gout recurrence 1 year after operation increased in patients who presented tophi; therefore, it is necessary to maintain appropriate blood uric acid level during perioperative period among patients undergoing orthopedic surgery.
Project description:ObjectivesTo examine whether gout is an independent risk factor for total joint replacement (TJR) and whether urate-lowering treatment (ULT) reduces this risk.MethodsUsing the Taiwan National Health Insurance database and the UK Clinical Practice Research Datalink, 74 560 Taiwan patients and 34 505 UK patients with incident gout were identified and age and sex matched to people without gout. Cox proportional hazards models and condition logistic regression were used to examine the risk of TJR in gout patients and the association between cumulative defined daily dose (cDDD) of ULT and TJR.ResultsThe prevalence rates of TJR in the patients at the time of diagnosis of gout and in people without gout were 1.16% vs 0.82% in Taiwan and 2.61% vs 1.76% in the UK. After a gout diagnosis, the incidence of TJR was higher in the patients with gout compared with those without (3.23 vs 1.91 cases/1000 person-years in Taiwan and 6.87 vs 4.61 cases/1000 person-years in the UK), with adjusted HRs of 1.56 (95% CI 1.45, 1.68) in Taiwan and 1.14 (1.05, 1.22) in the UK. Compared with patients with gout with <28 cDDD ULT, the adjusted ORs for TJR were 0.89 (95% CI 0.77, 1.03) for 28-90 cDDD, 1.03 (0.85, 1.24) for 90-180 cDDD and 1.12 (0.94, 1.34) for >180 cDDD ULT in Taiwan. In the UK, the respective ORs were 1.09 (0.83, 1.42), 0.93 (0.68, 1.27) and 1.08 (0.94, 1.24).ConclusionThis population-based study provides evidence from two nation populations that gout confers significant TJR risk, which was not reduced by current ULT.
Project description:The aim of this study was to systematically review the literature on effect of initiating urate-lowering treatment (ULT) during an acute attack of gout on duration of index attack and persistence on ULT. OVID (Medline), EMBASE and AMED were searched to identify randomized controlled trials (RCTs) of ULT initiation during acute gout attack published in English language. Two reviewers appraised the study quality and extracted data independently. Standardized mean difference (SMD) and relative risk (RR) were used to pool continuous and categorical data. Meta-analysis was carried out using STATA version 14. A total of 537 studies were selected. A total of 487 titles and abstracts were reviewed after removing duplicates. Three RCTs were identified. There was evidence from two high-quality studies that early initiation of allopurinol did not increase pain severity at days 10-15 [SMDpooled (95 % CI) 0.18 (-0.58, 0.93)]. Data from three studies suggested that initiation of ULT during an acute attack of gout did not associate with dropouts [RRpooled (95 % CI) 1.16 (0.58, 2.31)]. There is moderate-quality evidence that the initiation of ULT during an acute attack of gout does not increase pain severity and risk of ULT discontinuation. Larger studies are required to confirm these findings so that patients with acute gout can be initiated on ULT with confidence.
Project description:ObjectiveTo examine the association between cardioprotective use of low-dose aspirin and the risk of recurrent gout attacks among gout patients.MethodsWe conducted an online case-crossover study of individuals with gout over 1 year. The following information was obtained during gout attacks: the onset dates, symptoms and signs, medications, and exposure to potential risk factors, including daily aspirin use and dosage, during the 2-day hazard period prior to the gout attacks. The same exposure information was also obtained over 2-day control periods.ResultsOf the 724 participants analysed, 40.5% took aspirin ≤325 mg/day during either a hazard or a control period. Compared with no aspirin use, the adjusted OR of gout attacks increased by 81% (OR=1.81, 95% CI 1.30 to 2.51) for ≤325 mg/day of aspirin use on two consecutive days. The corresponding ORs were stronger with lower doses (eg, OR=1.91 for ≤100 mg, 95% CI 1.32 to 2.85). These associations persisted across subgroups by sex, age, body mass index categories and renal insufficiency status. Concomitant use of allopurinol nullified the detrimental effect of aspirin.ConclusionsOur findings suggest that the use of low-dose aspirin on two consecutive days is associated with an increased risk of recurrent gout attacks. Recommended serum urate monitoring with concomitant use and dose adjustment of a urate-lowering therapy among patients with gout may be especially important to help avoid the risk of gout attacks associated with low-dose aspirin.