Association Between Serum Bilirubin and Gingivitis in Kidney Transplant Patients.

Background: Bilirubin has been reported to have anti-inflammatory and anti-oxidant properties. These effects have shown to reduce oral complications in patients with chronic kidney disease (CKD). However, studies have been limited in immunosuppressed patients, such as kidney transplant recipients. This study therefore studied whether serum bilirubin has a protective effect against gingivitis even in immunosuppressed conditions.

Methods: Kidney transplant recipients who visited Dongan Hospital from 2018 to 2024 were recruited for the study. Patients with an unhealthy range of serum bilirubin were excluded. A total of 834 patients were divided into tertiles by serum bilirubin levels. The association between serum bilirubin and gingivitis was studied.

Results: From a total of 923 patients, 834 patients were eligible for the study. Patients were divided by the tertile of serum bilirubin levels. Compared to the lowest tertile, high serum bilirubin was associated with a lower odds ratio (OR) of 0.32 (95% confidence interval CI] = 0.11-0.77) in T2 and an OR of 0.22 (95% CI = 0.06-0.60) in T3. Associations were consistent after adjusting for both T2 (OR = 0.28, 95% CI = 0.10-0.72) and T3 (OR = 0.21, 95% CI = 0.06-0.58).

Conclusions: This study has shown that high bilirubin levels are associated with a decrease in gingivitis in kidney transplant recipients.