Background Gout incidence increases in a linear fashion with age until 70 years. It was reported that there was a trend of earlier gout onset. Few studies about clinical features of early-onset gout in China are reported.
Objectives To investigate the characteristics of early-onset gout in south China.
Methods Patients with primary gout were recruited between June 2012 and December 2016. Face to face interview was carried out to collect demographic information, clinical characteristics of gout and comorbid diseases. The patients with gout onset before age 30 were defined as early-onset group. The other gout patients were enrolled as control group.
Results (1) Five hundred and one gout patients were recruited, including 99 (19.8%) in the early-onset group and 402 (80.2%) in the control group. The onset age of the early-onset group was 24.2±5.8 (range 14–30) and the control group was 51.7±13.9 (range 31–84). There was no significant difference of gout duration between early-onset group and control group (P<0.05, Table 1). (2) Compared with the control group, the early-onset group presented lower frequency of flare in last year, higher serum uric acid and higher proportion of sUA>10mg/dl (P<0.05, Table 1). Body mass index (BMI) and prevalence of obesity were higher in the early-onset group (P<0.05, Table 1). The early-onset group exhibited lower prevalence of hypertension, diabetic mellitus, urolithiasis and chronic kidney disease (CKD) (P<0.05, Table 1). (3) There were 20 patients (20.2%) with tophi in the early-onset group. Compared with the 79 early-onset gout patients without tophi, the patients with tophi presented higher age (39.6±8.9 VS 29.1±6.2, P<0.001), duration of gout (12.6±4.8 VS 4.5±4.8, P<0.001), number of involved joints (12.5±9.3 VS 4.3±3.7, P<0.001) and prevalence of CKD (30.0% VS 10.1%, P=0.034), and lower BMI (23.7±3.7 VS 26.6±4.1 kg/m2, P=0.004). Logistic regression demonstrated that higher disease duration [OR 1.30, 95% CI (1.15, 1.46), P<0.001] and lower BMI [OR 0.80, 95% CI (0.67, 0.96), P=0.015] were associated with tophi in the early-onset gout patients.
Conclusions Early-onset gout exhibited higher sUA and was associated with obesity but not with hypertension, diabetic mellitus and renal insufficiency. Longer disease duration and lower BMI were associated with tophi in the early-onset gout patients.
Acknowledgements The present study was supported by Guangdong Natural Science Foundation, China (Grant no. 2014A030310086) to Qian-Hua Li.
Disclosure of Interest None declared