The prognosis of subjects showing a reduced estimated glomerular filtration rate without albuminuria in Japanese patients with type 2 diabetes: a cohort study for diabetic kidney disease

Anemia combined with albuminuria increases the risk of cardiovascular and renal events, regardless of a reduced glomerular filtration rate, in patients with type 2 diabetes: a prospective observational study

Aim

The incidence of cardiovascular and renal events was investigated in patients with type 2 diabetes who were classified according to anemia and the components of dialysis-independent chronic kidney disease (CKD) in a prospective observational study.

Methods

A population of 778 Japanese patients with type 2 diabetes was prospectively analyzed for 4 years. The outcomes were the incidence of cardiovascular events and renal events.

Results

In all subjects, the incidence of cardiovascular and renal events was found to be 5% and 11%, respectively. Even after adjusting for a reduced estimated glomerular filtration rate (eGFR <60 mL/min/1.73 m2), the incidence of cardiovascular events was significantly higher (hazard ratio [HR]: 5.73) in patients with anemia and albuminuria than in those without anemia and albuminuria. The incidence of renal events was significantly higher in patients with no anemia and albuminuria (HR: 2.93) and further in those with anemia and albuminuria (HR: 7.56) than in those without anemia and albuminuria even after adjusting for a reduced eGFR.

Conclusion

Anemia combined with albuminuria is a risk factor for vascular events in patients with type 2 diabetes, regardless of the eGFR.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13340-023-00637-x.

Comparison of Nonalbuminuric and Albuminuric Diabetic Kidney Disease Among Patients With Type 2 Diabetes: A Systematic Review and Meta-Analysis

BACKGROUND

Diabetic kidney disease (DKD) is one of most common complications of diabetes. Recently, the classical phenotype of DKD, which is characterized by albuminuria preceding renal insufficiency, has been challenged since a subset of diabetic patients with renal insufficiency but without albuminuria has been increasingly reported. However, the available evidence is inconsistent. Thus, the present systematic review will assess and summarize the available data regarding nonalbuminuric diabetic kidney disease (NADKD).

METHODS

PubMed, Embase, and Cochrane were searched for clinical trials related to NADKD. The results were limited to full-text articles published in English, without restrictions on the publication time. The quality of clinical trials was appraised, and the data were extracted. Meta-analysis was conducted using a random-effects model. Descriptive analysis was performed if the data were insufficient.

RESULTS

A final total of 31 articles were included in this review. The meta-analysis of 18 studies showed that compared with albuminuric DKD, patients with NADKD were older (MD = 1.04 years old, 95% CI [0.52, 1.57], p < 0.05); were more often women (Male RR = 0.74, 95% CI [0.68, 0.81], p < 0.05); had shorter diabetes duration (MD = -2.9 years, 95% CI [-3.63, -2.18], p < 0.05), lower HbA1c levels (MD = -0.34%, 95% CI [-0.42, -0.25], p < 0.05), and lower blood pressure (systolic blood pressure MD = -6.21 mmHg, 95% CI [-9.41, -3.0], p < 0.05; diastolic blood pressure MD = -1.27 mmHg, 95% CI [-2.15, 4.0], p < 0.05); less frequently experienced diabetic retinopathy (RR = 0.58, 95% CI [0.51, 0.67], p < 0.05); and less frequently used renin-angiotensin-aldosterone system (RAAS) inhibitors. The underlying pathology of NADKD might be different from that of the classic phenotype of DKD, which is associated with more advanced tubulointerstitial and vascular lesions but mild typical glomerular lesions. The annual estimated glomerular filtration rate decline tended to be lower in patients with NADKD than in those with albuminuric DKD. The risk for cardiovascular disease, end-stage renal disease, and all-cause death was lower for patients with NADKD than patients with albuminuric DKD.

CONCLUSIONS

The prevalence of NADKD has increased in recent decades, and its characteristics, pathology, and prognosis are different from those of albuminuric DKD; thus, diagnosis and treatment strategies should be different. More attention should be given to this phenotype.

Update on pathogenesis and diagnosis flow of normoalbuminuric diabetes with renal insufficiency

In recent decades, the prevalence of diabetic kidney disease has remained stable and appears to be a wide heterogeneity. Normoalbuminuric diabetes with renal insufficiency, which is characterized by a decline in the glomerular filtration rate in the absence of albuminuria, has been identified as an albuminuria-independent phenotype of diabetic kidney disease. Epidemiological data demonstrate that normoalbuminuric phenotype is prevalent. Compared to albuminuric phenotype, normoalbuminuric phenotype has distinct clinical characteristics and a wide heterogeneity of pathological features. Currently, the pathogenesis of normoalbuminuric phenotype remains unclear. Additionally, the flow of diagnosing normoalbuminuric phenotype is not perfect. In this article, we review the latest studies addressing the epidemiology, clinical characteristics, and pathology of normoalbuminuric phenotype. Based on the studies of clinical features and renal histopathologic changes, we attempt to propose an underlying pathogenesis model and a flow chart for diagnosing normoalbuminuric phenotype.

Different renoprotective effects of luseogliflozin depend on the renal function at the baseline in patients with type 2 diabetes: A retrospective study during 12 months before and after initiation

Aims

The safety and efficacy, particularly, the factors associated with the renal prognosis, were assessed over 12 months after the initiation of luseogliflozin therapy in Japanese patients with type 2 diabetes and renal impairment.

Methods

In total, 238 patients treated with luseogliflozin (2.5 mg, once daily) were studied as the safety analysis set. Two hundred and two subjects whose medication was continued over 12 months were investigated as the full analysis set. The subjects were divided into 3 groups based on the estimated glomerular filtration rate (eGFR): high eGFR (n = 49), normal eGFR (n = 116) and low eGFR (n = 37) groups.

Results

The body weight, systolic blood pressure, HbA1c and urinary protein excretion gradually decreased from baseline in all eGFR groups. While the eGFR was significantly reduced from baseline in the high and normal eGFR groups, the eGFR did not significantly differ over time in the low eGFR group. There was no marked difference in the frequency of adverse events that were specific for SGLT2 inhibitors among the 3 groups in the safety analysis set.

Conclusions

Luseogliflozin can preserve the renal function in the medium term in patients with type 2 diabetes and renal impairment without an increase in specific adverse events.