Evaluating the safety and short-term equivalence of colchicine versus prednisone in older patients with acute calcium pyrophosphate crystal arthritis (COLCHICORT): an open-label, multicentre, randomised trial.

BACKGROUND: Acute calcium pyrophosphate crystal arthritis causes intense joint pain mainly affecting older people. Because guidance and evidence remain scarce, management of this disease relies on expert opinion. We therefore aimed to compare the safety and short-term equivalence of low-dose colchicine with oral prednisone in older patients with acute calcium pyrophosphate crystal arthritis. METHODS: We did an open-label, multicentre, randomised, trial (COLCHICORT) at six hospitals in Paris and northern France. We enrolled patients who were admitted to hospital who were 65 years or older and who presented with acute calcium pyrophosphate crystal arthritis with a symptom duration of less than 36 h. Diagnosis of calcium pyrophosphate crystal arthritis was made by the identification of calcium pyrophosphate crystals on synovial fluid analysis or typical clinical presentation (onset of joint pain and swelling). Key exclusion criteria included absence of calcium pyrophosphate crystals on synovial fluid analysis or a history of gout. Participants were randomly allocated (1:1), using a centralised electronic treatment group allocation module, to receive either colchicine 1·5 mg on day 1 and 1 mg on day 2 (ie, the colchicine group) or oral prednisone 30 mg on days 1 and 2 (ie, the prednisone group). The primary outcome was change in joint pain (measured by visual analogue scale [VAS] from 0 mm to 100 mm) at 24 h. Equivalence was determined whether the 95% CI of the between-group difference at 24 h was within the -13 mm to +13 mm margin in the per-protocol analysis. Adverse events were recorded using the National Cancer Institute Common Terminology Criteria for Adverse Events (version 4.0). This trial is completed and is registered with ClinicalTrials.gov, NCT03128905. FINDINGS: Between Feb 5, 2018, and May 7, 2022, 111 patients who were admitted to hospital were randomly assigned (57 [51%] to the colchicine group and 54 [49%] to the prednisone group). 95 (86%) of 111 patients were included in the per-protocol analysis (49 [52%] in the colchicine group and 46 [48%] in the prednisone group). The median age was 88·0 years (IQR 82·0-91·0) and 69 (73%) of 95 participants were women and 26 (27%) were men. Acute calcium pyrophosphate crystal arthritis affected mainly the knee in 46 (48%) of 95 participants, the wrist in 19 (20%), and the ankle in 12 (13%). Pain VAS at baseline was 68 mm (SD 17). At 24 h, change in pain VAS was -36 mm (SD 32) in the colchicine group and -38 mm (SD 23) in the prednisone group. The between-group difference in change in pain VAS at 24 h was -1 mm (95% CI -12 to 10), showing equivalence between the two drugs. In the colchicine group, 12 (22%) of 55 patients had diarrhoea, one (2%) had hypertension, and none had hyperglycaemia. In the prednisone group, three (6%) of 54 had diarrhoea, six (11%) had hypertension, and three (6%) had hyperglycaemia. No deaths occurred in the colchicine group; two deaths occurred in the prednisone group, which were deemed unrelated to prednisone (one due to infectious valvular endocarditis leading to heart failure, and one due to a stroke). INTERPRETATION: Colchicine and prednisone exhibit equivalent short-term efficacy for the treatment of acute calcium pyrophosphate crystal arthritis, with different safety profiles in the older population. FUNDING: French Inter-regional Hospital Program of Clinical Research.

Monosodium urate burden assessed with dual-energy computed tomography predicts the risk of flares in gout: a 12-month observational study : MSU burden and risk of gout flare.

BACKGROUND: Predicting the risk of flares in patients with gout is a challenge and the link between urate burden and the risk of gout flare is unclear. The objective of this study was to determine if the extent of monosodium urate (MSU) burden measured with dual-energy computed tomography (DECT) and ultrasonography (US) is predictive of the risk of gout flares. METHODS: This prospective observational study recruited patients with gout to undergo MSU burden assessment with DECT (volume of deposits) and US (double contour sign) scans of the knees and feet. Patients attended follow-up visits at 3, 6 and 12 months. Patients having presented with at least one flare at 6 months were compared to those who did not flare. Odds ratios (ORs) (95% confidence interval) for the risk of flare were calculated. RESULTS: Overall, 64/78 patients included attended at least one follow-up visit. In bivariate analysis, the number of joints with the double contour sign was not associated with the risk of flare (p = 0.67). Multivariate analysis retained a unique variable: DECT MSU volume of the feet. For each 1 cm3 increase in DECT MSU volume in foot deposits, the risk of flare increased 2.03-fold during the first 6 months after initial assessment (OR 2.03 (1.15-4.38)). The threshold volume best discriminating patients with and without flare was 0.81 cm3 (specificity 61%, sensitivity 77%). CONCLUSIONS: This is the first study showing that the extent of MSU burden measured with DECT but not US is predictive of the risk of flares.

The lack of association between the burden of monosodium urate crystals assessed with dual-energy computed tomography or ultrasonography with cardiovascular risk in the commonly high-risk gout patient.

BACKGROUND: Gout is associated with higher cardiovascular risk that increases with disease severity. The objective of this study was to explore the relationship between the extent of monosodium urate (MSU) crystal deposition, assessed with ultrasonography (US) and dual-energy computed tomography (DECT), and cardiovascular risk. METHODS: Gout patients were included in this cross-sectional study to undergo DECT scans for the assessment of total MSU volume deposition in the knees and feet, and US to evaluate the number of joints with the double contour (DC) sign. Participants were screened for traditional cardiovascular risk factors, and levels of the American College of Cardiology (ACC)/American Heart Association (AHA) 10-year risk for heart disease or stroke were calculated. The primary endpoint was the Spearman correlation coefficient ρ between DECT MSU volume and cardiovascular risk. RESULTS: A total of 42 patients were included; they were predominantly male (40/42) and aged 63.0 ± 13.2 years. Overall, 28/42 patients presented with the metabolic syndrome and the average 10-year coronary event or stroke risk according to the ACC/AHA (n = 33) was 21 ± 15%. Correlations between DECT volumes of MSU deposits in the knees, feet, and knees + feet and cardiovascular risk according to the ACC/AHA were very poor, with ρ = 0.18, -0.01, and 0.13, respectively. The was no correlation between the number of joints with the DC sign and cardiovascular risk (ρ = -0.07). DECT MSU deposit volume was similar in patients with and without metabolic syndrome (p = 0.29). CONCLUSIONS: The extent of MSU burden does not increase the estimated risk of cardiovascular events in gout patients.

Ultrasonography and dual-energy computed tomography provide different quantification of urate burden in gout: results from a cross-sectional study.

BACKGROUND: Ultrasonography (US) and dual-energy computed tomography (DECT) can assess urate burden in gout. The objective of this study was to compare the quantification of urate deposition provided by US to the one provided by DECT. METHODS: Patients with a diagnosis of gout were prospectively recruited to undergo quantification of urate deposition using US and DECT. US examination for tophi and the double contour (DC) sign was performed on the knees and feet and corresponding DECT scans provided volumes of tophi and of overall urate deposition. The primary endpoint was the intra-class correlation coefficient (ICC) of the volume of the index tophus measured by US and DECT and its 95% confidence interval (CI 95%). RESULTS: Of the 64 patients included, 34 presented with at least one tophus on US. DECT inter-reader agreement for urate deposition was perfect with an ICC of 1 (1-1) and good for the measurement of the index tophus with an ICC of 0.69 (0.47-0.83). The ICC for the measurement of the index tophus between the two techniques was poor with a value of 0.45 (0.1-0.71). The average ratio between the index tophi volume as assessed by DECT and US was 0.65. The number of DC-positive joints did not correlate with DECT volume of overall deposits (Spearman correlation coefficient of 0.23). CONCLUSIONS: DECT measurements of tophi give smaller volumes to the same tophi measured with US, and US signs of urate deposition in joints do not correlate with overall DECT volumes of extra-articular deposition.