Table 3. Associations of ASV in Kidney Function Laboratory Measures With the Primary Composite Outcome Among Individuals With and Without CKD at Baseline.
| Variable | Model 1a | Model 2b | Model 3c | |||
|---|---|---|---|---|---|---|
| HR per 1-SD higher ASV (95% CI) | P value | HR per 1-SD higher ASV (95% CI) | P value | HR per 1-SD higher ASV (95% CI) | P value | |
| CKDd | ||||||
| BUN | 1.23 (1.12-1.34) | <.001 | 1.15 (1.03-1.28) | .01 | 1.39 (1.16-1.67) | <.001 |
| Creatinine | 1.21 (1.10-1.32) | <.001 | 1.20 (1.08-1.33) | .001 | 1.21 (1.07-1.37) | .002 |
| No CKD | ||||||
| BUN | 1.18 (1.09-1.27) | <.001 | 1.13 (1.03-1.23) | .008 | 1.13 (1.01-1.27) | .04 |
| Creatinine | 1.39 (123-1.57) | <.001 | 1.36 (1.18-1.56) | <.001 | 1.15 (0.99-1.34) | .06 |
Abbreviations: ACEI, angiotensin-converting enzyme inhibitor; ARB, angiotensin receptor blocker; ASV, average successive variability; BMI, body mass index (calculated as weight in kilograms divided by height in meters squared); BUN, blood urea nitrogen; CKD, chronic kidney disease; CVD, cardiovascular disease; HR, hazard ratio; NYHA, New York Heart Association; SBP, systolic blood pressure.
Model 1 was adjusted for age, sex, race/ethnicity, educational level, treatment arm, country of enrollment, and enrollment stratum (elevated natriuretic peptide levels or hospitalization for heart failure).
Model 2 was adjusted for the covariates in model 1 plus BMI, SBP, diabetes status (none, insulin dependent, or non–insulin dependent), alcohol use, smoking history, history of atrial fibrillation, ACEI or ARB use (yes or no), history of CVD, NYHA class, and baseline respective laboratory value (BUN, creatinine, potassium, sodium, or chloride).
Model 3 was adjusted for covariates of model 2 plus percentage change in respective laboratory value, variability in SBP and BMI, and spironolactone and loop diuretic medication dose as a time-varying covariate.
CKD was defined as an estimated glomerular filtration rate less than 60 mL/min per 1.73 m2.