Table 3.
Multivariable models of the continuous KRT solution group (phosphate containing versus phosphate free) as the main independent variable and study outcomes as the dependent variables in the whole and matched cohort
| Total Cohort | Matched Cohort | |||||||
|---|---|---|---|---|---|---|---|---|
| Variable | Estimate (% Change) | Model 95% Confidence Interval | P Value | Imputation Mean | Imputation 95% Confidence Interval | Estimate (% Change) | Model 95% Confidence Interval | P Value |
| Ventilator-free days at 28 d | ||||||||
| Phosphate versus phosphate-free group | 0.11a (12%) | 0.05 to 0.17 | <0.001b,c | 0.100 | 0.10 to 0.10 | 0.14 (15%) | 0.07 to 0.21 | <0.001b |
| ICU LOS | ||||||||
| Phosphate versus phosphate-free group | −0.19 (–17%) | −0.08 to –0.30 | <0.001b,c | −0.142 | 0.14 to –0.14 | — | — | — |
| Hospital LOS | ||||||||
| Phosphate versus phosphate-free group | −0.22 (–20%) | −0.12 to –0.32 | <0.001b,c | −0.148 | −0.15 to 0.15 | — | — | — |
Estimates are shown for nonimputed and imputed models. ICU, intensive care unit; LOS, length of stay.
Model interpretation: exponentiating the phosphate coefficient exp(0.11)=1.12; thus, the phosphate treatment is associated with more ventilator-free days (at 28 days) by 12% on average after adjusting for everything else.
The model was adjusted for age, sex, race, Charlson index, prevalent CKD, sequential organ failure score, total continuous KRT (CRRT) effluent rate, ventilator days prior to CRRT, CRRT duration, and admission to medical ICU.
The model was constructed with zero-inflated negative binomial logistic regression, with multiple imputation of missing data included in parentheses.