Comparative effects of sodium-glucose cotransporter 2 inhibitors versus dipeptidyl peptidase-4 inhibitors on kidney function decline in Japanese individuals with type 2 diabetes.

BACKGROUND: Limited direct comparative studies exist in terms of the effects of sodium-glucose cotransporter 2 inhibitors (SGLT2is) and dipeptidyl peptidase-4 inhibitors (DPP4is) on the kidney outcomes in Japanese individuals with type 2 diabetes. METHODS: This retrospective cohort study included 561 Japanese adults with type 2 diabetes, who were newly prescribed either an SGLT2i or a DPP4i and had an eGFR ≥ 30 mL/min/1.73 m2. The cohort comprised 207 women and 354 men, with a mean (± standard deviation) age of 63 (± 12) years. The exposure and outcome were SGLT2i or DPP4i initiation and eGFR slope during the overall follow-up period, restricted to participants who were followed for ≥2 years. We adopted the on-treatment analysis. Analysis of covariance was used to compare the adjusted eGFR slope between the two groups, incorporating 10 variables at baseline. RESULTS: During the median follow-up period of 3.4 years, least square mean (95% CI) eGFR slopes were -1.91 (-2.15, -1.67) and -1.12 (-1.58, -0.67) mL/min/1.73 m2/year in individuals treated with a DPP4i (n = 460) and an SGLT2i (n = 101), respectively, demonstrating statistical significance (p = 0.002). The robustness of this finding was strengthened by sensitivity analyses. CONCLUSIONS: This study provides potential evidence of the superiority of SGLT2is over DPP4is in slowing kidney function decline in Japanese adults with type 2 diabetes and eGFR ≥ 30 mL/min/1.73 m2.

Association between 1-year changes in urinary albumin-to-creatinine ratio and kidney disease progression in Japanese individuals with diabetes: a historical cohort study.

BACKGROUND: The National Kidney Foundation recently proposed a ≥ 30% decrease in urinary albumin-to-creatinine ratio (UACR) over 0.5-2 years as a surrogate endpoint for chronic kidney disease (CKD) progression in individuals with baseline UACR > 30 mg/g. This historical cohort study aimed to determine the applicability of a decrease in UACR, within as little as 1 year, as a surrogate endpoint for Japanese individuals with type 2 diabetes mellitus (T2D). METHODS: A total of 5067 individuals with T2D were divided into three groups based on 1-year change in UACR: ≥ 30% decrease (UACR decreased group), < 30% decrease and < 30% increase (UACR unchanged group), or ≥ 30% increase (UACR increased group). The primary endpoint was a composite of a ≥ 30% decline in estimated glomerular filtration rate (eGFR) or the initiation of kidney replacement therapy, whichever occurred first. RESULTS: At baseline, the proportions of individuals with normoalbuminuria, microalbuminuria, and eGFR ≥ 60 mL/min/1.73 m2 were 68.1%, 22.1%, and 75.5%, respectively. During a median follow-up of 6.8 years, 926 individuals (18.3%) reached the composite endpoint. Adjusted hazard ratios (vs. the UACR unchanged group) for the UACR decreased and increased groups were 0.758 (95% confidence interval [CI], 0.636-0.905; P = 0.002) and 1.304 (95% CI, 1.108-1.536; P = 0.001), respectively. CONCLUSIONS: These findings support the use of 1-year changes in UACR as a surrogate endpoint for the progression of CKD and the implementation of a ≥ 30% decrease in UACR as a positive efficacy endpoint in Japanese individuals with T2D and early-stage kidney disease.

Analysis of inflammatory cytokines and estimated glomerular filtration rate decline in Japanese patients with diabetic kidney disease: a pilot study.

Background: It is important to identify additional prognostic factors for diabetic kidney disease. Materials & methods: Baseline levels of ten cytokines (APRIL/TNFSF13, BAFF/TNFSF13B, chitinase 3-like 1, LIGHT/TNFSF14, TWEAK/TNFSF12, gp130/sIL-6Rß, sCD163, sIL-6Rα, sTNF-R1, sTNF-R2) were measured in two cohorts of diabetic patients. In one cohort (n = 777), 156 individuals were randomly sampled after stratification and their plasma samples were analyzed; in the other cohort (n = 69), serum samples were analyzed in all the individuals. The levels of cytokines between rapid (estimated glomerular filtration rate decline >5 ml/min/1.73 m2/year) and non-rapid decliners were compared. Results: Multivariate analysis demonstrated significantly high levels of LIGHT/TNFSF14, TWEAK/TNFSF12 and sTNF-R2 in rapid decliners. Conclusion: These three cytokines can be potential biomarkers for the progression of diabetic kidney disease.

Cross-sectional and longitudinal associations between dipstick hematuria and chronic kidney disease in patients with type 2 diabetes.

AIMS: To examine the association of dipstick hematuria with kidney function and albuminuria in patients with type 2 diabetes (T2D). METHODS: A total of 7,945 patients with T2D were studied. In the cross-sectional study, patients were classified into 6 groups based on the stage of albuminuria and estimated glomerular filtration rate (eGFR) of 60 mL/min/1.73 m2 at baseline. In the longitudinal study where patients were classified by the presence of hematuria, the primary composite endpoint was a 30% decrease in eGFR from baseline or the initiation of kidney replacement therapy. Other outcomes included eGFR slope and stage progression of albuminuria. RESULTS: Cross-sectionally, hematuria was more prevalent in patients with more advanced stages of albuminuria and with lower eGFR, independently of each other. In the longitudinal study, patients with hematuria experienced 50% increased incidence of the primary endpoint (p < 0.001). The eGFR slope was steeper in patients with hematuria than in those without hematuria (p < 0.001). On the other hand, hematuria was unlikely to be associated with the progression of albuminuria. CONCLUSIONS: In patients with T2D, dipstick hematuria was associated with prevalent albuminuria and reduced eGFR, as well as faster decline in kidney function but not higher risk of development or progression of albuminuria.

Effects of dietary protein intake on renal outcome and mortality in patients with advanced diabetic nephropathy.

BACKGROUND: The difficulty of adhering to a low-protein diet is a serious limitation of randomized controlled trials aimed at validating the efficacy of this therapy. In this observational study of patients with diabetic nephropathy, we examined the association of dietary protein intake (DPI) with renal outcome and mortality, taking into account the nutritional status. METHODS: We conducted a single-center historical cohort study of 449 adult Japanese patients with type 2 diabetes and the urinary albumin-to-creatinine ratio of ≥ 300 mg/g or estimated glomerular filtration rate of < 30 mL/min/1.73 m2. DPI was estimated with a formula using nitrogen levels in spot urine and body mass index. Malnutrition was defined as the Geriatric Nutritional Risk Index of ≤ 98. The primary and secondary endpoints were renal replacement therapy (RRT) initiation and mortality before RRT initiation, respectively. The Fine and Gray subdistribution hazard model was used to determine the relative effects of DPI on the respective endpoint. RESULTS: Decreased DPI was associated with lower incidence of RRT with an adjusted hazard ratio of 0.81 (95% confidence interval: 0.72-0.92, p < 0.001). The interaction between DPI and nutritional status with respect to mortality was significant (p interaction = 0.047). Decreased DPI was a risk factor for mortality in patients with malnutrition (p = 0.009) but not in those without malnutrition (p = 0.559). CONCLUSIONS: In patients with type 2 diabetic nephropathy, lower DPI was associated with lower incidence of RRT initiation, suggesting beneficial effects of a low-protein diet on kidneys. Conversely, lower DPI might lead to increased mortality in patients with malnutrition.

Temporal trends in the prevalence of albuminuria and reduced eGFR in Japanese patients with type 2 diabetes.

Changes over time have been shown in renal manifestations in individuals with diabetes in the United States; however, whether the trends are shared across ethnicities is unknown. We conducted this single-center serial cross-sectional study to determine temporal changes in albuminuria and reduced kidney function in Japanese patients with type 2 diabetes. This study included adult Japanese patients with type 2 diabetes who first visited our institute between 2004 and 2013. Temporal changes during the 10 years in the frequency of albuminuria ( ≥ 30 mg/g creatinine) and reduced eGFR ( < 60 mL/min/1.73 m2) were analyzed using the univariate and multivariate logistic regression analyses and Granger causality test. 5331 Japanese patients with type 2 diabetes, 1892 women and 3439 men, with the mean age of 56 ± 13 years, were studied. There was no change in the prevalence of albuminuria in the univariate analysis; however, a significantly decreasing trend was observed after adjustment for several covariates. On the other hand, patients with reduced eGFR significantly increased over time, although the statistical significance disappeared after adjustment for the covariates, including levels of serum uric acid and hemoglobin and use of renin-angiotensin inhibitors. The Granger causality test showed that time series for use of RAS inhibitors and BMI had a causative role in time series for reduced eGFR. In conclusion, prevalence of albuminuria decreased and that of reduced eGFR remained stable after adjustment for clinical characteristics in Japanese patients with type 2 diabetes during the last decade.

Effects of statins on the kidneys in patients with type 2 diabetes.

BACKGROUND: Effects of statins on kidneys in diabetic patients remain unclear. METHODS: This was an observational, historical cohort study of type 2 diabetic patients with estimated glomerular filtration rate (eGFR) ≥30 mL/min/1.73 m2. We studied 412 patients newly prescribed statins, and 946 controls without a prescription history of statins (including the follow-up period). Outcomes were annual change in eGFR, ≥30 % decrease in eGFR from baseline, and progression of albuminuria, analyzed using a propensity score matching. RESULTS: A total of 168 pairs were matched for propensity score. Annual eGFR change (mL/min/1.73 m2/year) in the statin group was greater than in controls (-2.24 vs. -1.56, p = 0.024). The hazard ratio of the statin group (vs. controls) for ≥30 % decrease in eGFR and progression of albuminuria was 1.74 (p = 0.082) and 0.85 (p = 0.624), respectively. When the statin group was classified by differences in statin solubility, eGFR change and hazard ratio for ≥30 % decrease in eGFR in the lipophilic statin group were greater than in controls (-2.64 vs. -1.71, p = 0.031 and 2.15, p = 0.049); however, the outcomes in the hydrophilic statin group were not different (-2.35 vs. -1.71, p = 0.106 and 1.08, p = 0.827). The hazard ratio of lipophilic and hydrophilic statin group (vs. controls) for progression of albuminuria was 1.31 (p = 0.552) and 0.69 (p = 0.367). In the analyses using the unmatched cohort, similar results were obtained. CONCLUSIONS: Statins have no beneficial effects on kidneys in diabetic patients. In fact, lipophilic statins might have potential harmful effects on kidney function.

Hypoglycemia Observed on Continuous Glucose Monitoring Associated With IGF-2-Producing Solitary Fibrous Tumor.

CONTEXT: Tumors producing IGF-2 (IGF-2oma) are a major cause of spontaneous hypoglycemia. The treatment mainstay is surgical resection. Many case reports note resolution of hypoglycemia after IGF-2oma resection; however, outcomes are variable according to tumor type. We report a case of resolving hypoglycemia, observed on continuous glucose monitoring, after resection of an IGF-2-producing solitary fibrous tumor of pleura and review the current literature. CASE REPORT: A 69-year-old woman presented with impaired consciousness because of hypoglycemia. An IGF-2oma was diagnosed as the cause for hypoglycemia because of decreased serum insulin and IGF-1, the presence of a pleural tumor, and a high-molecular-weight form of serum IGF-2 detected by Western immunoblot. Surgical resection was performed; pathological examination demonstrated a solitary fibrous tumor with low-grade malignancy. Continuous glucose monitoring showed reversal of hypoglycemia after tumor resection. Approximately 2 years after resection, the patient has no signs of tumor recurrence or hypoglycemia. CONCLUSIONS: An IGF-2-producing solitary fibrous tumor of pleura in this case caused hypoglycemia. From a search of the literature of 2004-2014, 32 cases of IGF-2oma with hypoglycemia that underwent radical surgery were identified; in 19 (59%) patients, hypoglycemia was reversed, and there was no subsequent recurrence. The remaining 13 (41%) patients experienced tumor recurrence or metastasis an average of 43 months after initial tumor resection. The tumor of the present case was a low-grade malignancy. Regular follow-up with biomarker monitoring of glucose metabolism and assessment of hypoglycemic symptomatology, in conjunction with imaging tests, is important for detecting possible tumor recurrence and metastasis.

Obesity as an effect modifier of the association between leptin and diabetic kidney disease.

AIMS/INTRODUCTION: Obesity has been shown to be a modifier of the association between leptin levels and cardiovascular events. We examined whether obesity modifies the association between serum leptin levels and the progression of diabetic kidney disease. MATERIALS AND METHODS: This was an observational longitudinal study on patients with type 2 diabetes. We enrolled 410 and 348 patients in the eGFR and ACR cohorts, respectively. Patients were classified into three groups by sex-specific tertile of leptin levels. Obesity was defined as body mass index ≥25 kg/m(2). Outcomes were the rate of change in estimated glomerular filtration rate (eGFR) and progression to a more advanced stage of albuminuria. RESULTS: In the eGFR cohort, the mean eGFR change during the median follow-up period of 4.7 years was -1.4 mL/min/1.73 m(2)/year. An interaction between leptin levels (low, medium or high) and obesity (present or absent) on the change in eGFR was detected (P interaction = 0.003). In the lean group, adjusted eGFR decline in patients with low leptin was steeper than that in patients with medium leptin (2.1 and 0.8 mL/min/1.73 m(2)/year, P = 0.023). In the obese group, patients with high leptin had a steeper adjusted eGFR decline than those with medium leptin (1.7 and 0.6 mL/min/1.73 m(2)/year, P = 0.044). In the ACR cohort, 29 patients showed progression of albuminuria during the median follow-up period of 3.9 years. There was no interaction between leptin levels and obesity on the outcome (P interaction = 0.094). CONCLUSIONS: Obesity might modify the effects of leptin on kidney function decline in patients with type 2 diabetes.