Risk factors of urate deposition on ultrasound in patients with gout / 中华风湿病学杂志

ABSTRACT

Objective To explore the risk factors of urate deposition on ultrasound in patients with gout.Methods All the gout patients who visited our center between February 2015 and February 2017 and underwent ultrasound examination of bilateral knees,ankles and first metatarsophalangeal joints (MTP1) were enrolled.Subgroup analysis was done depending on whether double contour sign (DCS) or tophus was found on ultrasound.Main statistical analysis methods were t test,chi-square test and logistic regression model.Results One hundred and twenty-six patients were included.DCS was found in 50(39.7％) patients and tophus was found in 48 (38.1％) patients.The serum uric acid (SU) level of the DCS positive group was signi-ficantly higher than the DCS negative group [(602±79) μmol/L vs (538±101) μmol/L,t=3.998,P=0.044].The hyperuicemia duration of the two groups were (186±87) months and (130±77) months,which was significantly different (t=3.330,P=0.002).The hyperuicemia duration of the tophus positive group was significantly higher than tophus negative group [(175±102) months vs (138±96) months,t=2.003,P=0.045].The SU level and hyperuicemia duration were independent risk factors of positive DCS in gout patients [OR =1.006,95％ CI (1.002,1.01 1);OR=1.028,95％CI (1.013,1.042)].The hyperuicemia duration was independent risk factor of positive tophus in gout patients [OR=1.004,95％CI (1.000,1.007)].Receiver operating characteristic curve (ROC) curve showed gout patient whose hyperuricemia duration was longer than 94months and SU level was higher than 505.5 μmol/L were more likely to have positive DCS in joints;meanwhile,patient whose hyperuricemia duration was longer than 137 months were more likely to have positive tophus in joints.Conclusion Gout patients who have positive DCS and tophus on ultrasound have longer hyperuicemia duration.Positive DCS is also related with patients' higher serum levels.The hyperuicemia duration is an independent risk factor of urate deposition on ultrasound in patients with gout.