Association Between Circulating GDF‐15 and Cardio‐Renal Outcomes and Effect of Canagliflozin: Results From the CANVAS Trial

Background Studies have suggested that sodium glucose co‐transporter 2 inhibitors exert anti‐inflammatory effects. We examined the association of baseline growth differentiation factor‐15 (GDF‐15), a marker of inflammation and cellular injury, with cardiovascular events, hospitalization for heart failure (HF), and kidney outcomes in patients with type 2 diabetes in the CANVAS (Canagliflozin Cardiovascular Assessment Study) and determined the effect of the sodium glucose co‐transporter 2 inhibitor canagliflozin on circulating GDF‐15. Methods and Results The CANVAS trial randomized 4330 people with type 2 diabetes at high cardiovascular risk to canagliflozin or placebo. The association between baseline GDF‐15 and cardiovascular (non‐fatal myocardial infarction, non‐fatal stroke, cardiovascular death), HF, and kidney (40% estimated glomerular filtration rate decline, end‐stage kidney disease, renal death) outcomes was assessed using multivariable adjusted Cox regression models. During median follow‐up of 6.1 years (N=3549 participants with available samples), 555 cardiovascular, 129 HF, and 137 kidney outcomes occurred. Each doubling in baseline GDF‐15 was significantly associated with a higher risk of cardiovascular (hazard ratio [HR], 1.2; 95% CI, 1.0‒1.3), HF (HR, 1.5; 95% CI, 1.2‒2.0) and kidney (HR, 1.5; 95% CI, 1.2‒2.0) outcomes. Baseline GDF‐15 did not modify canagliflozin’s effect on cardiovascular, HF, and kidney outcomes. Canaglifozin treatment modestly lowered GDF‐15 compared with placebo; however, GDF‐15 did not mediate the protective effect of canagliflozin on cardiovascular, HF, or kidney outcomes. Conclusions In patients with type 2 diabetes at high cardiovascular risk, higher GDF‐15 levels were associated with a higher risk of cardiovascular, HF, and kidney outcomes. Canagliflozin modestly lowered GDF‐15, but GDF‐15 reduction did not mediate the protective effect of canagliflozin.

Effect of body mass index on the association between alcohol consumption and the development of chronic kidney disease

The influence of body mass or metabolic capacity on the association between alcohol consumption and lower risks of developing chronic kidney disease (CKD) is not fully elucidated. We examined whether the body mass index (BMI) affects the association between drinking alcohol and CKD. We defined CKD as an estimated glomerular filtration rate decline < 60 mL/min/1.73 m2 and/or positive proteinuria (≥ 1+). Participants were 11,175 Japanese individuals aged 40–74 years without baseline CKD who underwent annual health checkups. Daily alcohol consumption at baseline was estimated using a questionnaire, and the participants were categorized as “infrequent (occasionally, rarely or never),” “light (< 20 g/day),” “moderate (20–39 g/day),” and “heavy (≥ 40 g/day).” Over a median 5-year observation period, 936 participants developed CKD. Compared with infrequent drinkers, light drinkers were associated with low CKD risks; adjusted hazard ratios (95% confidence intervals) were 0.81 (0.69–0.95). Stratified by BMI (kg/m2), moderate drinkers in the low (< 18.5), normal (18.5–24.9), and high (≥ 25.0) BMI groups had adjusted hazard ratios (95% confidence intervals) of 3.44 (1.60–7.42), 0.75 (0.58–0.98), and 0.63 (0.39–1.04), respectively. Taken together, the association between alcohol consumption and CKD incidence was not the same in all the individuals, and individual tolerance must be considered.

Regression Modeling of the Antioxidant-to-Nephroprotective Relation Shows the Pivotal Role of Oxidative Stress in Cisplatin Nephrotoxicity

The clinical utility of the chemotherapeutic drug cisplatin is significantly limited by its nephrotoxicity, which is characterized by electrolytic disorders, glomerular filtration rate decline, and azotemia. These alterations are consequences of a primary tubulopathy causing injury to proximal and distal epithelial cells, and thus tubular dysfunction. Oxidative stress plays a role in cisplatin nephrotoxicity and cytotoxicity, but its relative contribution to overall toxicity remains unknown. We studied the relation between the degree of oxidative reduction (provided by antioxidant treatment) and the extent of nephrotoxicity amelioration (i.e., nephroprotection) by means of a regression analysis of studies in animal models. Our results indicate that a linear relation exists between these two parameters, and that this relation very nearly crosses the value of maximal nephroprotection at maximal antioxidant effect, suggesting that oxidative stress seems to be a pivotal and mandatory mechanism of cisplatin nephrotoxicity, and, hence, an interesting, rationale-based target for clinical use. Our model also serves to identify antioxidants with enhanced effectiveness by comparing their actual nephroprotective power with that predicted by their antioxidant effect. Among those, this study identified nanoceria, erythropoietin, and maltol as highly effective candidates affording more nephroprotection than expected from their antioxidant effect for prospective clinical development.

The risk of consequent nephropathy following initial weight loss in diabetic patients treated with sodium glucose cotransporter 2 inhibitors

Background There is a controversy over the association between obesity and the risk of renal events in patients with type 2 diabetes mellitus (T2DM). Furthermore, whether body weight (BW) loss following sodium glucose cotransporter 2 inhibitor (SGLT2i) treatment associated with risk of adverse renal events is unknown. Methods We used medical data from a multi-center healthcare provider in Taiwan, enrolling 8992 T2DM patients with a baseline/following-up BW data available after around 12 weeks of SGLT2i treatment, from June 1, 2016 to December 31, 2018. Patients were followed up until the occurrence of composite renal outcome (estimated glomerular filtration rate decline > 40% or end-stage kidney disease) or the end of study period, whichever occurred first. Results Participants were divided into six baseline BMI categories: < 18.5 (n = 55); 18.5–22.9 (n = 985); 23.0–24.9 (n = 1389); 25.0–29.9 (n = 3941); 30.0–34.9 (n = 1973); and ≥ 35.0 kg/m2 (n = 649). There were 38.9%, 23.5%, 24.7%, 8.4%, 2.7%, and 1.8% of patients experienced no-BW loss, initial BW loss of 0.0–2.4%, 2.5–4.9%, 5.0–7.4%, 7.5–9.9%, and ≥ 10.0%, associated with SGLT2i treatment, respectively. Compared with patients with normal BMI (BMI: 18.5–22.9 kg/m2), underweight (BMI: < 18.5 kg/m2) was associated with a higher risk of composite renal outcome (adjusted hazard ratio (aHR) [95% confidence intervals (CI)]: 2.17; [1.16–4.04]), whereas pre-obese (BMI: 25.0–29.9 kg/m2) associated with the lowest risk of composite renal outcome (0.52; [0.40–0.68]) after multivariate adjustment. Compared with those without BW loss after SGLT2i treatment, BW loss of 0.0–2.4% (0.55; [0.43–0.70]) and 2.5–4.9% (0.78; [0.63–0.98]) were associated with a lower risk, whereas BW loss ≥ 10.0% associated with a higher risk of composite renal outcome (1.61; [1.06–2.46]) after multivariate adjustment. Conclusion A modest BW loss of 0–5% associated with SGLT2i treatment was associated with a favorable renal outcome. Caution should be taken for whom are underweight at baseline or have a pronounced BW loss ≥ 10.0% associated with SGLT2i treatment, which was associated with a worse renal outcome.

Long-Term Outcomes of Kidney Transplants from Older/Marginal Donors: A Cohort Study

<b><i>Introduction:</i></b> To safely expand the donor pool, we introduced a strategy of biopsy-guided selection and allocation to single or dual transplantation of kidneys from donors &#x3e;60 years old or with hypertension, diabetes, and/or proteinuria (older/marginal donors). Here, we evaluated the long-term performance of this approach in everyday clinical practice. <b><i>Methods:</i></b> In this single-center cohort study, we compared outcomes of 98 patients who received one or two biopsy-evaluated grafts from older/marginal donors (“recipients”) and 198 patients who received nonhistologically assessed single graft from ideal donors (“reference-recipients”) from October 2004 to December 2015 at the Bergamo Transplant Center (Italy). <b><i>Results:</i></b> Older/marginal donors and their recipients were 27.9 and 19.3 years older than ideal donors and their reference-recipients, respectively. KDPI/KDRI and donor serum creatinine were higher and cold ischemia time longer in the recipient group. During a median follow-up of 51.9 (interquartile range 23.1–88.6) months, 11.2% of recipients died, 7.1% lost their graft, and 16.3% had biopsy-proven acute rejection (BPAR) versus 3.5, 7.6, and 17.7%, respectively, of reference-recipients. Overall death-censored graft failure (rate ratio 0.78 [95% CI 0.33–2.08]), 5-year death-censored graft survival (94.3% [87.8–100.0] vs. 94.2% [90.5–98.0]), BPAR incidence (rate ratio 0.87 [0.49–1.62]), and yearly measured glomerular filtration rate decline (1.18 ± 3.27 vs. 0.68 ± 2.42 mL/min/1.73 m², <i>p</i> = 0.37) were similar between recipients and reference-recipients, respectively. <b><i>Conclusions:</i></b> Biopsy-guided selection and allocation of kidneys from older/marginal donors can safely increase transplant activity in clinical practice without affecting long-term outcomes. This may help manage the growing gap between organ demand and supply without affecting long-term recipient and graft outcomes.