Clinical features and long-term outcomes of diabetic kidney disease - A prospective cohort study from China.

BACKGROUND: Information regarding the clinical phenotypes of diabetic kidney disease (DKD) might guide better practice for clinicians. We aim to compare the clinical features and long-term outcomes of proteinuric and non-proteinuric phenotypes of DKD, based on a prospective cohort of Chinese population.

METHODS: Altogether 8811 Chinese participants with diabetes were included. Kidney function decline was defined as estimated glomerular filtration rate <60 mL/min·1.73 m-2 . The presence of proteinuria by urine dipstick test was further divided into micro-proteinuria (trace or 1+) and overt-proteinuria (≥2+). Participants were then stratified into 5 groups: no DKD, isolated kidney function decline, isolated micro-proteinuria, isolated overt-proteinuria, and proteinuria combined with kidney function decline. Outcomes include the first occurrence of composite cardiovascular events, end-stage renal disease (ESRD), and all-cause mortality.

MAIN FINDINGS: After a median follow-up of 6.9 years, there were 646 composite cardiovascular events, 31 ESRD events, and 718 deaths. Isolated kidney function decline was only associated with the higher risk of ESRD (HRs 31.33 (95% CI 3.65-269.27)). Participants of overt-proteinuria and proteinuria combined with kidney function decline phenotypes were associated with increased risk of all predefined adverse outcomes.

CONCLUSIONS: Proteinuric and non-proteinuric DKD phenotypes might follow different pathophysiological pathways, and result in heterogeneous clinical features and prognosis.