The Bidirectional Relationship between Chronic Kidney Disease and Hyperuricemia: Evidence from a Population-Based Prospective Cohort Study.

BACKGROUND: Although several studies have examined the association between chronic kidney disease (CKD) and hyperuricemia (HUA), the direction of the association remains unclear. We aimed to investigate whether there was a bidirectional association between them. METHODS: The present study was conducted in three analyses. Analysis I included 25,433 participants free of HUA at baseline to evaluate the associations between CKD and estimated glomerular filtration rate (eGFR) with incident HUA. Analysis II had 28,422 participants free of CKD at baseline to analyze the relationships between HUA and serum uric acid (sUA) with new-onset CKD. Cox proportional hazards regression models were applied to evaluate the association involved in Analysis I and II. Analysis III included 31,028 participants with complete data and further dissected the bidirectional association between sUA and eGFR using cross-lag models. RESULTS: New-onset HUA and CKD were observed in the first round of the follow-up study among 1597 and 1212 participants, respectively. A significantly higher risk of HUA was observed in individuals with CKD compared to individuals without CKD (HR = 1.58, 95% CI: 1.28-1.95). The adjusted HRs (95% CIs) of HUA were 3.56 (2.50-5.05) for the participants in the group of eGFR less than 60 mL·min-1·1.73 m-2, 1.61 (1.42-1.83) for those in the group of eGFR between 60 and 90 mL·min-1·1.73 m-2, and 1.74 (1.42-2.14) for those in the group of eGFR more than 120 mL·min-1·1.73 m-2, compared with the group of eGFR between 90 and 120 mL·min-1·1.73 m-2. A higher risk of CKD was also observed in individuals with HUA compared to individuals without HUA (HR = 1.28, 95% CI: 1.12-1.47). Compared with the first quintile of sUA, the adjusted HR (95% CI) of CKD was 1.24 (1.01-1.51) for the participants in the fourth quantile. There was a bidirectional relationship between sUA and eGFR, with the path coefficients (ρ1 = -0.024, p < 0.001) from baseline eGFR to follow-up sUA and the path coefficients (ρ2 = -0.015, p = 0.002) from baseline sUA to follow-up eGFR. CONCLUSIONS: The present study indicated that CKD and HUA were closely associated, and there was a bidirectional relationship between sUA and eGFR.

Evaluating the added predictive ability of MMP-9 in serum for Kawasaki disease with coronary artery lesions.

To investigate the predictive ability of serum matrix metalloproteinase-9 (MMP-9) in the acute phase of Kawasaki disease (KD) with coronary artery lesions (CALs). Patients with KD hospitalized in Lanzhou University Second Hospital, Northwest China, from November 2015 to January 2018 were retrospectively reviewed, and clinical trial indicators and peripheral blood specimens were collected before intravenous immunoglobulin therapy treatment. The independent risk factors were determined using multivariate regression analysis. The net reclassification improvement (NRI) and integrated discrimination improvement (IDI) were used to quantitatively evaluate the ability of MMP-9 to improve the efficiency of predicting KD with CALs. The white cell, neutrophil percentage, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) were higher in patients with higher MMP-9, and the monocyte percentage was higher in patients with lower MMP-9. Logistic regression analysis revealed that long-term fever; elevated CRP, ESR, platelets (PLT), and MMP-9; and low albumin (ALB) levels were independent predictors of KD with CALs. A predictive model of KD with CALs using fever duration, CRP, ESR, PLT, and ALB showed significantly improved predictive ability when MMP-9 was added to the model (the area under the curve increased by 0.02; no change in sensitivity; specificity increased from 81.48% to 87.04%; NRI value: 13.46%; IDI value: 5.00%, p<0.05). Adding MMP-9 to traditional risk factors may improve prediction of CALs, the overall predictive ability of model 2 was increased by 5%.