RATIONALE & OBJECTIVE: Limited evidence concerns fine particulate matter (with aerodynamic diameter ≤ 2.5μm [PM]) exposure and the risk for kidney failure with replacement therapy (KFRT). This study assessed whether PM exposure was associated with progression of chronic kidney disease (CKD) to KFRT.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS: 6,628 adult patients with CKD were recruited from the Advanced CKD Program in Taiwan between 2003 and 2015.

EXPOSURE

Satellite-based spatiotemporal models were used to calculate each individual's 1-year PM exposure before the date of enrollment into the Advanced CKD Program.

OUTCOMES

Time to KFRT (defined as initiation of maintenance hemodialysis, peritoneal dialysis, or kidney transplantation) and time to all-cause mortality.

ANALYTICAL APPROACH

Multivariable proportional hazard regression analyses were used to estimate the association of PM with KFRT and all-cause mortality. Restricted cubic splines were used to explore dose-response relationships.

RESULTS

The study population included 6,628 adult patients with CKD who were aged 20 to 90 years. 941 KFRT events and 1,653 deaths occurred during follow-up. The adjusted HR for progression to KFRT was 1.19 (95% CI, 1.08-1.31) per 7.8μg/m greater PM, an amount spanning the interquartile range. There was evidence of a dose-response relationship (adjusted HRs of 1.16 [95% CI, 0.90-1.51], 1.19 [95% CI, 0.94-1.52], and 1.42 [95% CI, 1.12-1.80] for low, medium, and high PM levels). There was no significant association between PM and all-cause mortality (adjusted HR, 1.01 [95% CI, 0.95-1.08]).

LIMITATIONS

Misclassification of PM exposure assessment and the potential for residual confounding.

CONCLUSIONS

Our findings suggest that long-term exposure to PM is associated with increased risk for progression to KFRT in patients with CKD.