Bilirubin and risk of ischemic heart disease in Korea: a two-sample Mendelian randomization study

SLCO1B1 variants and the risk of antituberculosis drug-induced hepatotoxicity: a systematic review and meta-analysis

Aims: To evaluate the association between SLCO1B1 gene polymorphisms and susceptibility of antituberculosis drug-induced hepatotoxicity (ATDH). Methods: We searched the PubMed, Cochrane Library, Embase, Web of Science, Wan Fang and China National Knowledge Infrastructure database from inception to 2022. Results: Nine case-control studies with 1129 cases and 2203 controls were included. Among four SNPs reported in two or more studies, the final results indicated that SNP rs4149014 was significantly associated with decreased ATDH risk (dominant model, odds ratio: 0.73; 95% CI: 0.55-0.97; p = 0.03; allele model, odds ratio: 0.69; 95% CI: 0.55-0.86; p = 0.001), and the trial sequential analysis also confirmed this significant association. Conclusion: SLCO1B1 gene SNP rs4149014 was significantly associated with lower risk of ATDH susceptibility.

Novel prognostic score based on the preoperative total bilirubin-albumin ratio and fibrinogen-albumin ratio in ampullary adenocarcinoma

BACKGROUND

The preoperative total bilirubin-albumin ratio (TBAR) and fibrinogen-albumin ratio (FAR) have been proven to be valuable prognostic factors in various cancers.

AIM

To detect the prognostic value of TBAR and FAR in ampullary adenocarcinoma (AC) patients who underwent curative pancreaticoduodenectomy.

METHODS

AC patients who underwent curative pancreaticoduodenectomy in the National Cancer Center of China between 1998 and 2020 were retrospectively reviewed. The prognostic cutoff values of TBAR and FAR were determined through the best survival separation model. Then, a novel prognostic score combining TBAR and FAR was calculated and validated through the logistic regression analysis and Cox regression analysis.

RESULTS

A total of 188 AC patients were enrolled in the current study. The best cutoff values of TBAR and FAR for predicting overall survival were 1.7943 and 0.1329, respectively. AC patients were divided into a TBAR-low group (score = 0) vs a TBAR-high group (score = 1) and a FAR-low group (score = 0) vs a FAR-high group (score = 1). The total score was calculated as a novel prognostic factor. Multivariable logistic regression analysis revealed that a high score was an independent protective factor for recurrence [score = 1 vs score = 0: Odds ratio (OR) = 0.517, P = 0.046; score = 2 vs score = 0 OR = 0.236, P = 0.038]. In addition, multivariable survival analysis also demonstrated that a high score was an independent protective factor in AC patients (score = 2 vs score = 0: Hazard ratio = 0.230, P = 0.046).

CONCLUSION

A novel prognostic score based on preoperative TBAR and FAR has been demonstrated to have good predictive power in AC patients who underwent curative pancreaticoduodenectomy. However, more studies with larger samples are needed to validate this conclusion.

Association of Different Total Bilirubin Levels with Prognosis of Peritoneal Dialysis-Associated Peritonitis

Background and Objectives: Peritoneal dialysis-associated peritonitis (PDAP) poses significant challenges in peritoneal dialysis (PD) patient management and outcomes. Total bilirubin has gained attention due to its antioxidant and immunomodulatory properties. However, its relationship with PDAP prognosis remains underexplored. Materials and Methods: We conducted a retrospective single-center study involving 243 PDAP patients stratified into tertile-based groups according to total bilirubin levels. The association between total bilirubin levels and treatment failure risk was investigated through statistical analyses and restricted cubic spline curve analysis. Results: Our analysis revealed a non-linear correlation between total bilirubin levels and PDAP treatment failure risk. At total bilirubin levels below 8.24 µmol/L, a protective effect was observed, while levels exceeding this threshold heightened the risk of treatment failure. Conclusions: This study unveils a dual role of total bilirubin in PDAP prognosis. Below a certain threshold, it confers protection, while higher levels exacerbate the risk of treatment failure. These findings emphasize the need for further investigation in larger, multicenter prospective studies to validate and elucidate the mechanisms behind bilirubin's impact on PDAP, potentially guiding the development of targeted therapeutic strategies.

Heme Oxygenase-1 and Blood Bilirubin Are Gradually Activated by Oral D-Glyceric Acid

It has been shown that small doses of oral D-glyceric acid (DGA) activate mitochondrial metabolism and reduce inflammation among 50-60-year-old healthy volunteers. The present results with the same small doses reveal that after a 4-day DGA regimen, a dose of DGA activated the HO-1 pathway acutely, while enhanced inflammatory status after the 4-day DGA regimen seemed to be able to downregulate the HO-1 pathway in non-acute measurement. Blood bilirubin was strongly upregulated towards the end of the altogether 21-day study period with positive associations towards improved inflammation and reduced blood triglycerides. After the 4-day DGA regimen, hepatic inflow of blood bilirubin with albumin as the carrier was clearly upregulated in the lower-aerobic-capacity persons. At the same time also, blood triglycerides were down, pointing possibly to the activation of liver fatty acid oxidation. The combination of activated aerobic energy metabolism with transient HO-1 pathway activation and the upregulation of blood bilirubin may reduce the risks of chronic diseases, especially in aging. Furthermore, there exist certain diseases with unsatisfactorily-met medical needs, such as fatty and cholestatic liver diseases, and Parkinson's disease, that can be possibly ameliorated with the whole-body mechanism of the action of the DGA regimen.

Serum bilirubin and kidney function: a Mendelian randomization study

Background

Further investigation is needed to determine the causal effects of serum bilirubin on the risk of chronic kidney disease (CKD).

Methods

This study is a Mendelian randomization (MR) analysis. Among the well-known single-nucleotide polymorphisms (SNPs) related to serum bilirubin levels, rs4149056 in the SLCO1B1 gene was selected as the genetic instrument for single-variant MR analysis, as it was found to be less related to possible confounders than other SNPs. The association between genetic predisposition for bilirubin levels and estimated glomerular filtration rate (eGFR) or CKD was assessed in 337 129 individuals of white British ancestry from the UK Biobank cohort. Two-sample MR based on summary-level data was also performed. SNPs related to total or direct bilirubin levels were collected from a previous genome-wide association study and confounder-associated SNPs were discarded. The independent CKDGen meta-analysis data for CKD were employed as the outcome summary statistics.

Results

The alleles of rs4149056 associated with higher bilirubin levels were associated with better kidney function in the UK Biobank data. In the summary-level MR, both of the genetically predicted total bilirubin {per 5 µmol/L increase; odds ratio [OR] 0.931 [95% confidence interval (CI) 0.871-0.995]} and direct bilirubin [per 1 µmol/L increase; OR 0.910 (95% CI 0.834-0.993)] levels were significantly associated with a lower risk of CKD, supported by the causal estimates from various MR sensitivity analyses.

Conclusion

Genetic predisposition for higher serum bilirubin levels is associated with better kidney function. This result suggests that higher serum bilirubin levels may have causal protective effects against kidney function impairment.

The Nonlinear Relationship Between Total Bilirubin and Coronary Heart Disease: A Dose-Response Meta-Analysis

Background: Evidence suggests that the total bilirubin has a protective effect on coronary heart disease (CHD), but the dose-response relationship remains controversial, and there is no meta-analysis to assess the relationship.

Methods: As of October 1, 2021, relevant literature was selected from four databases (PubMed, Web of Science, Cochrane Library, and Embase) by using a retrieval strategy. The dose-response curve between the total bilirubin and CHD was fitted by a restricted cubic spline. Stata 12.0 was used for statistical analysis.

Results: A total of 170,209 (6,342 cases) participants from 7 prospective studies were analyzed in our meta-analysis. We calculated the pooled relative risks (RRs) and 95% CIs for the association between serum bilirubin level and risk of CHD using random-effects models. Compared with the first quantile, the bilirubin level in the third quantile had a protective effect on the risk of CHD (RR, 0.90; 95% CI, 0.82–0.99). The restricted cubic spline functions depicted a U-type curve relationship between bilirubin (3.42–49 μmol/L) and CHD (P_linear < 0.001). When the bilirubin level was in the range of 3.42–13μmol/L, the protective effect of bilirubin on CHD was enhanced with increasing bilirubin levels. When the bilirubin level exceeded 13μmol/L, the protective effect of bilirubin weakened, and a dangerous effect gradually appeared with further increases in bilirubin levels.

Conclusions: Compared with a low bilirubin level, a high bilirubin level has a protective effect on the risk of CHD, and there was a U-shaped dose-response relationship between them.

Association between Alcohol Consumption and Serum Cortisol Levels: a Mendelian Randomization Study

BACKGROUND

Several studies have reported conflicting results regarding the relationship between alcohol consumption and cortisol levels. However, the causality between alcohol consumption and cortisol levels has not been evaluated.

METHODS

This study examined 8,922 participants from the Dong-gu Study. The aldehyde dehydrogenase 2 (ALDH2) rs671 polymorphism was used as an instrumental variable for alcohol consumption. The association between the genetically predicted alcohol consumption and cortisol level was evaluated with Mendelian randomization (MR) using two-stage least squares regression.

RESULTS

Alcohol consumption was positively associated with the serum cortisol level in both sexes in the observational analysis. In the MR analysis, the genetically predicted alcohol consumption was positively related to the cortisol level in men, with cortisol levels increasing by 0.18 μg/dL per drink per day. However, there was no relationship in women in the MR analysis.

CONCLUSION

The predicted alcohol consumption according to the ALDH2 rs671 polymorphism was positively related to the cortisol levels, suggesting a causal relationship between alcohol consumption and cortisol levels.

Exploring the causal pathway from bilirubin to CVD and diabetes in the UK biobank cohort study: Observational findings and Mendelian randomization studies

BACKGROUND AND AIMS

Some studies reported that mildly elevated serum bilirubin levels were associated with decreased risk of cardiovascular disease (CVD) and diabetes. Whether these are causal relationships remains unclear. This study aims to examine the causal effects of bilirubin on CVD, diabetes and their subtypes.

METHODS

The data we used in this study includes individual data from the UK Biobank cohort with 331,002 white British participants, and summary data from published genome wide associations studies (GWAS) findings. We used individual data to perform logistic regression for the observational study and two-stage least squares method for the Mendelian randomization (MR) study. We also performed several traditional MR methods and MR-TRYX by summary data.

RESULTS

The observational study supported the association relationships between bilirubin and CVD and diabetes and their subtypes. Results of MR showed strong evidence for negative causal associations of log_e total bilirubin with CVD [OR 0.92, 95%CI 0.88-0.95, p-value 2.15 × 10^-6], coronary heart disease [OR 0.90, 95%CI 0.85-0.96, p-value 1.54 × 10^-3] and hypertensive diseases [OR 0.91, 95%CI 0.88-0.95, p-value 5.89 × 10^-6], but no evidence for diabetes [OR 0.94, 95%CI 0.86-1.02, p-value 0.14] and its subtypes. We also obtained similar results for direct bilirubin. We found that blood pressure, cholesterol, C-reactive protein, alcohol and white blood cell count played important roles in the causal pathway from bilirubin to CVD. Two sample MR and sensitivity analyses showed consistent results with one sample MR.

CONCLUSIONS

Genetically determined bilirubin was negatively associated with the risk of CVD but had no evident causal association with diabetes in the UK Biobank cohort of white British.