Long-term Trends in Infection-Related Mortality in Adults Treated With Maintenance Dialysis.

RATIONALE & OBJECTIVE: Infection is 1 of the top 3 causes of death in patients receiving maintenance dialysis. We evaluated the trends over time and risk factors for infection-related deaths among people receiving dialysis.

STUDY DESIGN

Retrospective cohort study.

SETTING & PARTICIPANTS: We included all adults who began dialysis between 1980 and 2018 in Australia and New Zealand.

EXPOSURE

Age, sex, dialysis modality, and dialysis era.

OUTCOME

Infection-related death.

ANALYTICAL APPROACH

Incidence was described and standardized mortality ratios (SMR) calculated for infection-related death. Fine-Gray subdistribution hazards models were fitted, with non-infection-related death and kidney transplantation treated as competing events.

RESULTS

The study comprised 46,074 patients who received hemodialysis and 20,653 who were treated with peritoneal dialysis who were followed for 164,536 and 69,846 person-years, respectively. There were 38,463 deaths during the follow-up period, 12% of which were ascribed to infection. The overall rate of mortality from infection (per 10,000 person-years) was 185 and 232 for patients treated with hemodialysis and peritoneal dialysis, respectively. The rates were 184 and 219 for males and females, respectively; and 99, 181, 255, and 292 for patients aged 18-44, 45-64, 65-74, 75 years and over, respectively. The rates were 224 and 163 for those commencing dialysis in years 1980-2005 and 2006-2018, respectively. The overall SMR declined over time, from 37.1 (95% CI, 35.5-38.8) in years 1980-2005 to 19.3 (95% CI, 18.4-20.3) in years 2006-2018, consistent with the declining 5-year SMR trend (P<0.001). Infection-related mortality was associated with being female, older age, and Aboriginal and/or a Torres Strait Islander or Māori.

LIMITATIONS

Mediation analyses defining the causal relationships between infection type and infection-related death could not be undertaken as disaggregating the data was not feasible.

CONCLUSIONS

The excess risk of infection-related death in patients on dialysis has improved substantially over time but remains more than 20 times higher than in the general population.