Inflammation in the early phase after kidney transplantation is associated with increased long‐term all‐cause mortality

In the general population, low‐grade inflammation has been established as a risk factor for all‐cause mortality. We hypothesized that an inflammatory milieu beyond the time of recovery from the surgical trauma could be associated with increased long‐term mortality in kidney transplant recipients (KTRs). This cohort study included 1044 KTRs. Median follow‐up time post‐engraftment was 10.3 years. Inflammation was assessed 10 weeks after transplantation by different composite inflammation scores based on 21 biomarkers. We constructed an overall inflammation score and five pathway‐specific inflammation scores (fibrogenesis, vascular inflammation, metabolic inflammation, growth/angiogenesis, leukocyte activation). Mortality was assessed with Cox regression models adjusted for traditional risk factors. A total of 312 (29.9%) patients died during the follow‐up period. The hazard ratio (HR) for death was 4.71 (95% CI: 2.85–7.81, p < .001) for patients in the highest quartile of the overall inflammation score and HRs 2.35–2.54 (95% CI: 1.40–3.96, 1.52–4.22, p = .001) for patients in the intermediate groups. The results were persistent when the score was analyzed as a continuous variable (HR 1.046, 95% CI: 1.033–1.056, p < .001). All pathway‐specific analyses showed the same pattern with HRs ranging from 1.19 to 2.70. In conclusion, we found a strong and consistent association between low‐grade systemic inflammation 10 weeks after kidney transplantation and long‐term mortality.