Baseline demographic, clinical and biochemical characteristic of all participants and according to the usage of allopurinol.

Data are presented as frequency (percentage), mean ± standard deviation or *median (interquartile range). Parametric data was analysed using unpaired two-tailed t-test or Pearson's χ2 unless otherwise specified. §Log-transformed prior to analyses. §§Analysed using Mann-Whiteney U test. Abbreviations: ACR = albumin creatinine ratio; bpm = beats per minutes; CVD = cardiovascular disease; ACEI = angiotensin converting enzyme inhibitor; ARB = Angiotensin II receptor blocker; eGFR = estimate glomerular filtration rate, hsCRP = high sensitivity C-reactive protein; SAF = skin autofluorescence.