Association of serum total bilirubin levels with progressive renal decline and end-stage kidney disease: 10-year observational cohort study in Japanese patients with diabetes

A Novel Kidney Failure Prediction Model in Individuals With CKD: Impact of Serum Bilirubin Levels

CONTEXT

Predicting the progression of chronic kidney disease (CKD) to end-stage kidney disease (ESKD) is crucial for improving patient outcomes.

OBJECTIVE

To reveal the highly predictive activity of serum bilirubin levels for the progression of CKD to ESKD, and to develop and validate a novel ESKD prediction model incorporating serum bilirubin levels.

METHODS

We assessed the relative importance of 20 candidate predictors for ESKD, including serum bilirubin levels, in a CKD cohort (15 ≤ estimated glomerular filtration rate [eGFR] < 60 mL/min/1.73 m2), and subsequently developed a prediction model using the selected variables. The development cohort comprised 4103 individuals with CKD who underwent follow-up at Kyushu University Hospital, Japan, from 2008 to 2018. The primary outcome was incident ESKD, defined as an eGFR < 15 mL/min/1.73 m2, chronic dialysis, or renal transplantation.

RESULTS

The mean follow-up time was 7.0 ± 4.2 years, during which 489 individuals (11.9%) progressed to ESKD. The Cox proportional hazard model selected eGFR, serum bilirubin, proteinuria, age, diabetes, gender, hypertension, serum albumin, and hemoglobin in order of their importance. The predictive performance of the model was optimized by incorporating these 9 variables in discrimination evaluated by time-dependent area under the curve (AUC). This model also demonstrated excellent calibration. Additionally, this model exhibited excellent predictive performance in both discrimination (2-year AUC: 0.943, 5-year AUC: 0.935) and calibration in a validation cohort (n = 2799).

CONCLUSION

Serum bilirubin levels were strong predictors for the progression of CKD to ESKD. Our novel model that incorporates serum bilirubin levels could accurately predict ESKD in individuals with CKD.

The impact of brominated flame retardants exposure on serum total bilirubin: A cross-sectional analysis

BACKGROUND

Brominated flame retardants (BFRs) are harmful, bioaccumulative, and persistent environmental pollutants, posing significant health risks. Elevated bilirubin levels can cause neurotoxicity and damage to the heart, liver, kidneys, and other organs. This study utilizes National Health and Nutrition Examination Survey (NHANES) data to investigate the association between exposure to BFRs and total bilirubin (TB) levels in adult participants.

METHODS

Based on data from the NHANES 2007-2016, TB levels were divided into tertiles. Spearman's rank correlation was used to analyze the relationship between individual BFRs and TB levels. Weighted linear regression analysis, restricted cubic splines (RCS), and stratified analysis were conducted to assess the correlation between individual BFRs and TB levels. Weighted quantile sum (WQS) regression and quantile-based g-computation (QGC) analysis were used to comprehensively evaluate the impact of BFRs exposure on serum TB levels.

RESULTS

The study included 5831 participants. The results showed that PBB153, PBDE17, PBDE47, PBDE85, PBDE99, PBDE100, PBDE209, and PBDE183 were significantly correlated with TB levels (p <  0.05), with PBDE183 having the highest Spearman rank correlation coefficient of 0.292. After adjusting for confounding factors, most BFR remained significantly positively correlated with TB, while PBDE153 (β: - 0.031, 95%CI: - 0.317, 0.255, p =  0.829) and PBDE66 (β: 0.285, 95%CI: - 0.208, 0.777, p =  0.253) were not statistically significant. RCS analysis indicated that PBDE153 concentration had a significant U-shaped correlation with TB (p <  0.05), while PBDE17, PBDE99, PBDE154, and PBDE209 had an inverted "J"-shaped correlation (p <  0.05). PBB153, PBDE66, PBDE85, and PBDE183 also exhibited significant nonlinear S-shaped correlations with TB (p <  0.05). After stratification by age and gender, most individual BFR remained significantly positively correlated with TB levels (p <  0.05). WQS regression and QGC analysis indicated that mixed BFRs exposure was positively correlated with TB levels (β: 0.553, 95%CI: 0.384, 0.722, p <  0.001 and β: 1.060, 95%CI: 0.587, 1.532, p <  0.001), with PBDE183 contributing the most.

CONCLUSIONS

BFRs exposure is significantly positively correlated with TB levels, further suggesting the potential health impact of BFRs exposure on humans.

Total bilirubin level is associated with acute kidney injury in neonates admitted to the neonatal intensive care units: based on MIMIC-III database

OBJECTIVE

The objective of this study was to investigate the association between total bilirubin and acute kidney injury (AKI) in neonates admitted to neonatal intensive care units (NICU).

METHODS

All data utilized were extracted from Medical Information Mart for Intensive Care-III (MIMIC-III) in this retrospective cohort study. The primary outcome was the occurrence of AKI during hospitalization in the NICU, and the exposure was the initial measurement of total bilirubin levels within 24 h of neonatal admission to the NICU. The relationship between serum total bilirubin and AKI was evaluated by employing univariate and multivariate logistic regression models. Additionally, subgroup analyses were conducted based on birth weight, sepsis, and mechanical ventilation.

RESULTS

This retrospective cohort study included a population of 1,726 neonates, and 95 neonates developed AKI. Total bilirubin, as a continuous variable, was linked with decreased AKI risk among neonates admitted to the NICU [odds ratio (OR) = 0.77, 95% confidence interval (CI): 0.64-0.92]. Similarly, when total bilirubin levels were categorized by tertiles, tertiles 3 showed a significant association with decreased AKI risk (OR = 0.39, 95%CI: 0.19-0.83). The relationship of total bilirubin level and AKI was also existent among neonates admitted to the NICU who were underweight, had not sepsis, and received mechanical ventilation.

CONCLUSION

Total bilirubin level may be a protective factor for the risk of developing AKI.

Exploring the inverse relationship between serum total bilirubin and systemic immune-inflammation index: insights from NHANES data (2009-2018)

BACKGROUND

Bilirubin is known for its multifaceted attributes, including antioxidant, anti-inflammatory, immunomodulatory, and antiapoptotic properties. The systemic immune-inflammation index (SII) is a recent marker that reflects the balance between inflammation and immune response. Despite the wealth of information available on bilirubin's diverse functionalities, the potential correlation between the total bilirubin (TB) levels and SII has not been investigated so far.

METHODS

Leveraging data from the National Health and Nutrition Examination Survey spanning 2009-2018, the TB levels were categorized using tertiles. Employing the chi-squared test with Rao and Scott's second-order correction and Spearman's rank correlation analysis, the association between TB and SII was examined. The potential nonlinearities between TB and SII were evaluated using restricted cubic spline (RCS) analysis. Weighted linear regression, adjusted for covariates, was used to explore the correlation between TB and SII, with further subgroup analyses.

RESULTS

A total of 16,858 participants were included, and the findings revealed significant SII variations across TB tertiles (p < 0.001). The third tertile (Q3) exhibited the lowest SII level at 495.73 (295.00) 1000 cells/µL. Spearman rank correlation disclosed the negative association between TB and SII. RCS analysis exposed the lack of statistically significant variations in the nonlinear relationship (p > 0.05), thereby providing support for a linear relationship. Weighted linear regression analysis underscored the negative correlation between TB and SII (β 95% CI - 3.9 [- 5.0 to  - 2.9], p < 0.001). The increase in the TB levels is associated with a significant linear trend toward decreasing SII. After controlling for relative covariates, this negative correlation increased (p < 0.001). Subgroup analysis confirmed the significant negative TB-SII association.

CONCLUSION

A notable negative correlation between TB and SII implies the potential protective effects of bilirubin in inflammation-related diseases.

Temporal alteration of serum bilirubin levels and its renoprotective effects in diabetic kidney disease: exploring the hormonal mechanisms

Objective

This current study represents a novel endeavor to scrutinize the correlation between the temporal alteration in serum total bilirubin (TBIL) concentrations and the rate of estimated glomerular filtration rate (eGFR). Additionally, this study aims to probe the plausible molecular mechanism underpinning the renoprotective effects of bilirubin concerning its hormonal characteristics.

Materials and methods

In this study, a cohort of 103 patients diagnosed with DKD and receiving medical care at Dongzhimen Hospital were recruited and monitored over a period of 2-7 years. The progression of DKD was ascertained using a threshold of eGFR decline > -5.48%/year. To assess the relationship between the annual change in serum TBIL levels (%/year) and the slope of eGFR, multivariate binary logistic regression analysis was employed. Furthermore, the ROC curve analysis was employed to determine the cut-off value for TBIL levels (%/year).

Results

The use of multivariate binary logistic regression models revealed that serum TBIL levels (%/year) exhibited a significant correlation with the slope of eGFR. Moreover, the ROC curve analysis indicated a cut-off value of -6.729%/year for TBIL levels (%/year) with a sensitivity of 0.75 and specificity of 0.603, in diagnosing eGFR decline >-5.48%/year.

Conclusions

The findings of this study suggest that the sustained elevation of serum bilirubin concentration within the physiological range can effectively retard the progression of Diabetic Kidney Disease (DKD). Furthermore, the hormonal attributes of bilirubin may underlie its renoprotective effects.

Association between serum total bilirubin and diabetic kidney disease in US diabetic patients

Background

Bilirubin has been widely reported to be a protective factor against diabetic kidney disease (DKD) in Asian populations. However, few large-sample analyses have been conducted in American populations. This study aimed to investigate the association between serum total bilirubin (STB) level and DKD in a US diabetic cohort.

Methods

This cross-sectional study enrolled participants from the National Health and Nutrition Examination Survey (NHANES) 2003-2018. Univariate and multivariate logistic regression analyses were performed to assess the association between STB level and DKD. Three models were conducted to control the potential confounding factors. Subgroup analysis was carried out for further validation.

Results

Among the 5,355 participants, the median age [interquartile range (IQR)] was 62 [52-71] years; 2,836 (52.96%) were male, and 1,576 (29.43%) were diagnosed with DKD. In the entire cohort, no significant association between STB level and DKD was observed in any logistic regression models (p > 0.05). Subgroup analysis revealed that, in U.S. diabetic males, STB levels > 11.98 µmol/L were associated with a nearly 30% lower risk of DKD than STB levels ≤ 8.55 µmol/L. Additionally, a moderate STB level (8.56-11.98 μmol/L) was found associated with a nearly 25% lower risk of DKD in U.S. diabetic patients over 65 years old.

Conclusion

The association of STB level with DKD may depict differences across diverse populations, among which the impact of race, sex, and age requires thorough consideration and relevant inferences should be interpreted cautiously.

Association of Serum Bilirubin Levels with Macro- and Microvascular Complications in Chinese People with Type 2 Diabetes Mellitus: New Insight on Gender Differences

Background

Previous studies suggested protective effects of bilirubin against cardiovascular disease, with a possible gender difference. However, the relationship between serum total bilirubin (TBIL) with diabetic macro- and microvascular complications remains unknown. We aimed to examine the association of macro- and microvascular complications with serum TBIL levels.

Methods

Serum TBIL was measured in 648 patients with T2DM. Demographic and clinical data were obtained from the inpatient medical record system. Serum TBIL was measured with an automatic biochemistry analyzer according to routine protocols. Parameters of vascular complications, including ankle-brachial index, carotid intima-media thickness, estimated glomerular filtration rate and the urinary albumin to creatinine ratio, were measured and calculated. The association between TBIL and diabetic macro- and microvascular complications was analyzed.

Results

In multivariable logistic regression, after adjustment for age, sex, body mass index and diabetic duration, higher serum TBIL levels were significantly associated with decreased odds of microalbuminuria (OR = 0.31, [95% CI] 0.16-0.61, P = 0.003) and chronic kidney disease (OR = 0.19, [95% CI] 0.09-0.41, P < 0.001). These associations were only found in male but not in female patients. However, no significant relationship was found between TBIL and peripheral arterial disease or carotid hypertrophy.

Conclusion

Our findings suggest that physiological higher TBIL level might be a protective factor for diabetic microvascular complications.