Search

Background: SGLT2 inhibition decreases albuminuria and reduces the risk of kidney disease progression in patients with type 2 diabetes. These benefits are unlikely to be mediated by improvements in glycaemic control alone. Therefore, we aimed to examine the kidney effects of the SGLT2 inhibitor dapagliflozin in patients with proteinuric kidney disease without diabetes. Methods: DIAMOND was a randomised, double-blind, placebo-controlled crossover trial done at six hospitals in Canada, Malaysia, and the Netherlands. Eligible participants were adult patients (aged 18–75 years) with chronic kidney disease, without a diagnosis of diabetes, with a 24-h urinary protein excretion greater than 500 mg and less than or equal to 3500 mg and an estimated glomerular filtration rate (eGFR) of at least 25 mL/min per 1·73 m2, and who were on stable renin–angiotensin system blockade. Participants were randomly assigned (1:1) to receive placebo and then dapagliflozin 10 mg per day or vice versa. Each treatment period lasted 6 weeks with a 6-week washout period in between. Participants, investigators, and study personnel were masked to assignment throughout the trial and analysis. The primary outcome was percentage change from baseline in 24-h proteinuria during dapagliflozin treatment relative to placebo. Secondary outcomes were changes in measured GFR (mGFR; via iohexol clearance), bodyweight, blood pressure, and concentrations of neurohormonal biomarkers. Analyses were done in accordance with the intention-to-treat principle. This study is registered with ClinicalTrials.gov, NCT03190694. Findings: Between Nov 22, 2017, and April 5, 2019, 58 patients were screened, of whom 53 (mean age 51 years [SD 13]; 32% women) were randomly assigned (27 received dapagliflozin then placebo and 26 received placebo then dapagliflozin). One patient discontinued during the first treatment period. All patients were included in the analysis. Mean baseline mGFR was 58·3 mL/min per 1·73 m2 (SD 23), median proteinuria was 1110 mg per 24 h (IQR 730–1560), and mean HbA1c was 5·6% (SD 0·4). The difference in mean proteinuria change from baseline between dapagliflozin and placebo was 0·9% (95% CI −16·6 to 22·1; p=0·93). Compared with placebo, mGFR was changed with dapagliflozin treatment by −6·6 mL/min per 1·73 m2 (–9·0 to −4·2; p

Albuminuria and a reduced glomerular filtration rate are conventional predictors of a future decline in kidney function in patients with type 2 diabetes mellitus. Using a nested case-control study we assessed whether circulating transforming growth factor-β1 (TGF-β1) and bone morphogenetic protein-7 (BMP-7) levels more accurately predict renal end points than the conventional markers. Cases were defined as those who developed a renal end point (doubling of serum creatinine to at least 200 μmol/l, the need for renal replacement therapy, or death due to renal disease) during the study. Using propensity scoring, two controls were selected for each of 281 cases. Participants who developed renal end points had significantly higher total TGF-β1, lower BMP-7 levels, and a higher total TGF-β1 to BMP-7 ratio at baseline. A graded increase in risk was found in individuals with lower BMP-7 levels (odds ratio 24.07, for the lowest to the highest tertile), or significantly higher TGF-β1 levels (odds ratio for the highest to the lowest tertile, 8.43). The area under the receiver operating characteristic curve (c-statistic) for the conventional predictors was 0.73. Using BMP-7 and total and active TGF-β1, the c-statistic was 0.94 (significantly higher to conventional predictors). Thus, our results suggest these novel kidney markers are better predictors of renal progression than the conventional predictors in patients with type 2 diabetes mellitus. © 2012 International Society of Nephrology.