Table 6:
Summary of estimation of mediation effects.
| Effect | Estimate (95%CI) | Bootstrap bias corrected 95% CI | P-value |
|---|---|---|---|
| Total effect (TE) | 0.98 (0.97–1.00)a | 0.97–0.99 | .052 |
| Controlled direct effect (CDE) | 0.98 (0.97–0.99)a | 0.97–0.99 | .04 |
| Natural direct effect (NDE) | 0.98 (0.97–0.99)a | 0.97–0.99 | .04 |
| Natural indirect effect (NIE) | 1.00 (0.99–1.00)a | 0.99–1.00 | .29 |
| Percentage mediated (PM) | −7.65 (−24.06–8.76) | −118.45–3.18 | .36 |
| Percentage due to interaction (PDI) | 4.60 (−4.28–13.48) | −2.22–19.98 | .31 |
| Percentage eliminated (PE) | −3.17 (−13.23–6.88) | −154.95–2.23 | .53 |
Represents odds ratios adjusted for differences in urine albumin-creatinine ratio and history of congestive heart failure.
TE represents the association of eGFR with CV events after accounting for all confounders in the model. CDE represents the association of eGFR with CV events after controlling for CA-AKI (i.e. mediator). NDE represents the association of eGFR with CV events without controlling for CA-AKI. NIE is the association of eGFR with CV events mediated through CA-AKI (non-significant). PM represents the percentage of NIE in relation to TE. Only 7.6% of the association of eGFR with CV events is mediated by CA-AKI (non-significant). PDI represents the percentage of the TE due to the interaction between eGFR and CA-AKI, which is only 4.6% (non-significant). PE represents the percentage of the association of eGFR with CV events that could be eliminated by intervening on CA-AKI. Because PE is only −3.1%, even if CA-AKI is eliminated, we can only expect a 3.1% lowering in CV events (non-significant).