High-normal albuminuria and incident chronic kidney disease in a male nondiabetic population

Change in Urine Albumin-to-Creatinine Ratio and Risk of Diabetic Peripheral Neuropathy in Type 2 Diabetes: A Retrospective Cohort Study

PURPOSE

This study aimed to assess association between change in urine albumin-to-creatinine ratio (UACR) and the risk of diabetic peripheral neuropathy (DPN) in type 2 diabetes mellitus.

PATIENTS AND METHODS

A retrospective study was performed, which included 185 individuals with type 2 diabetes. At baseline, and at two-year follow-up, we collected basic data, recorded symptoms and signs of DPN, measured biochemical indicators, composite motor nerve conduction velocity (composite MCV), and composite sensory nerve conduction velocity (composite SCV).

RESULTS

Changes of composite SCV, MCV and TCSS among different changes in UACR in patients without DPN and with DPN were not significantly different. An increase in UACR ≥30% (OR 3.059, 95%; CI: 1.012-9.249) suggested a risk for new-onset DPN. Based on ROC curve analysis, the areas under the curve were 0.654 ± 0.066 for change of UACR levels in non-DPN patients.

CONCLUSION

Change in UACR and NCV was not related in patients without DPN and with DPN; change in UACR ≥30% suggested a risk for new-onset DPN.

Frequency of alcohol drinking modifies the association between salt intake and albuminuria: a 1-year observational study

Albuminuria is an important risk factor for end-stage kidney disease and cardiovascular mortality. This 1-year observational study aimed to assess the effect modification of alcohol drinking on the association between salt intake and albuminuria. Overall, 448 employees at a pharmaceutical company in Japan who underwent annual health checkups in both 2017 and 2018 were evaluated. The main exposure of interest was drinking frequency at their first checkups categorized as rarely, occasionally, and daily. To assess the association between the changes in salt intake and albuminuria, the differences in salt intake estimated from single-spot urine specimens and the urinary albumin-to-creatinine ratio (UACR) between 2017 and 2018 were calculated for each subject. A multivariable-adjusted linear regression model showed a significant association between ∆salt intake and ∆Log UACR (per 1 g/day of ∆salt intake, adjusted ß 0.16 [95% confidence interval 0.14, 0.19]) and an effect modification between drinking frequency and ∆salt intake (P for interaction = 0.088). The association between ∆salt intake and ∆Log UACR was enhanced by drinking frequency in a dose-dependent manner (per 1 g/day of ∆salt intake, adjusted ß 0.13 [0.06, 0.19], 0.16 [0.12, 0.20], and 0.20 [0.13, 0.27] in rare, occasional, and daily drinkers, respectively). In conclusion, the results of the present study indicated that salt-induced albuminuria was enhanced in subjects with higher drinking frequency, suggesting that salt restriction may have a stronger renoprotective effect in subjects with higher drinking frequency.

Differential metabolic profile associated with the condition of normoalbuminuria in the hypertensive population

BACKGROUND AND AIM

Albuminuria is an indicator of sub-clinical organ damage and a marker of cardiovascular risk and renal disease. A percentage of hypertensive patients develop albuminuria despite being under chronic suppression of the renin-angiotensin system (RAS). We previously identified urinary metabolites associated with the development of albuminuria. In this study, we searched for metabolic alterations which reflect different levels within the condition of normoalbuminuria.

PATIENTS, MATERIALS AND METHODS

Urine from 48 hypertensive patients under chronic RAS suppression was analysed. They were classified according to the albumin/creatinine ratio (ACR) into 3groups: Normoalbuminuria (<10mg/g); high-normal (10-30mg/g in men, or 20-40mg/g in women); and moderately high albuminuria (microalbuminuria, 30-200mg/g or 40-300mg/g, respectively). The metabolome was analysed by mass spectrometry and a correlation analysis was performed between altered metabolite levels and ACR.

RESULTS

Oxaloacetate, 3-ureidopropionate, guanidoacetate and malate show significant variation between the normo and micro groups. Additionally, these metabolites are able to differentiate between patients in the normo and high-normal range. A significant correlation between metabolites and ACR was found. Observed variations point to alterations in the energy metabolism already in patients with albuminuria in the high-normal range.

CONCLUSIONS

The association between the molecular panel consisting of 3-ureidopropionate, oxaloacetate, malate and guanidoacetate and different levels of albuminuria is confirmed. A metabolic fingerprint was also identified showing variations within the condition of normoalbuminuria allowing an earlier molecular stratification of patients.

High-normal albuminuria is strongly associated with incident chronic kidney disease in a nondiabetic population with normal range of albuminuria and normal kidney function

BACKGROUND

Albuminuria and estimated glomerular filtration rate (eGFR) are clinically measured to evaluate the severity of chronic kidney disease (CKD). The aim of our study was to clarify the association between clinical parameters, including albuminuria and eGFR, and the risk of incident CKD in a nondiabetic population with normal range of albuminuria and eGFR.

METHODS

A 10-year follow-up, retrospective cohort study involving 317 Japanese men (mean age, 42 years) with eGFR ≥ 90 mL/min/1.73 m² and urine albumin-to-creatinine ratio (UACR) < 30 mg/gCr was performed. Participants were free of diabetes mellitus. Multivariate logistic regression approaches were used to assess independent predictors of the incidence of CKD.

RESULTS

Twenty-nine (9%) participants developed CKD (eGFR < 60 mL/min/1.73 m² and/or UACR ≥ 30 mg/gCr) through 10 years of follow-up. At the baseline examination, age, blood pressure, UACR, and eGFR were higher in participants who developed CKD than in those without CKD. After adjustment for confounders, high-normal albuminuria (P < 0.001) and hypertension (P = 0.045) were associated with an increased incidence of CKD. From receiver-operating characteristic curves, UACR ≥ 7.0 mg/gCr was defined as high-normal albuminuria. Logistic regression analysis also showed that, in addition to presence of hypertension, UACR ≥ 7.0 mg/gCr was identified as an independent risk of incident CKD within 10 years after adjustment for age, body mass index, smoking status, and dyslipidemia [UACR: odds ratio (OR) 17.36 (95% CI 6.16-48.93, P < 0.001)].

CONCLUSION

High-normal albuminuria and hypertension are associated with incident CKD in a nondiabetic population with normal-range UACR and eGFR.