Table 3.
Baseline salt excretion and change in BP at 6 mo for measured (A) and estimated (B) 24‐h urinary sodium excretion
| Change in 6‐mo office systolic BP | Change in 6‐mo 24‐h ambulatory systolic BP | |||||||
|---|---|---|---|---|---|---|---|---|
| B | 95% CI | P value | B | 95% CI | P value | |||
| (A) | ||||||||
| Model 1 | ||||||||
| Baseline urinary sodium, 10 mmol/24u | −0.20 | −1.11 | 0.71 | .67 | −0.56 | −1.58 | 0.47 | .28 |
| Baseline sodium excretion quartile | −0.75 | −5.83 | 4.34 | .77 | −0.83 | −6.52 | 4.86 | .77 |
| Model 2 | ||||||||
| Baseline urinary sodium, 10 mmol/24u | −0.43 | −1.28 | 0.41 | .31 | −0.50 | −1.54 | 0.54 | .34 |
| Baseline sodium excretion quartile | −1.46 | −6.16 | 3.23 | .54 | −0.68 | −6.40 | 5.04 | .81 |
| Model 3 | ||||||||
| Baseline urinary sodium, 10 mmol/24u | −0.53 | −1.55 | 0.48 | .30 | −0.20 | −1.43 | 1.03 | .75 |
| Baseline sodium excretion quartile | −1.85 | −7.23 | 3.52 | .49 | 1.17 | −5.24 | 7.59 | .72 |
| Model 4 | ||||||||
| Baseline urinary sodium, 10 mmol/24u | −0.53 | −1.55 | 0.49 | .30 | −0.20 | −1.44 | 1.04 | .75 |
| Baseline sodium excretion quartile | −1.85 | −7.26 | 3.57 | .50 | 1.17 | −5.30 | 7.65 | .72 |
| Model 5 | ||||||||
| Baseline urinary sodium, 10 mmol/24u | −0.58 | −1.60 | 0.45 | .26 | −0.33 | −1.60 | 0.94 | .60 |
| Baseline sodium excretion quartile | −2.36 | −7.86 | 3.14 | .39 | 0.32 | −6.47 | 7.11 | .93 |
| Model 6 | ||||||||
| Baseline urinary sodium, 10 mmol/24u | −0.60 | −1.64 | 0.45 | .26 | −0.39 | −1.70 | 0.91 | .55 |
| Baseline sodium excretion quartile | −2.35 | −7.92 | 3.21 | .40 | 0.20 | −6.70 | 7.09 | .95 |
| Model 7 | ||||||||
| Baseline urinary sodium, 10 mmol/24u | −0.59 | −1.65 | 0.46 | .26 | −0.39 | −1.69 | 0.92 | .55 |
| Baseline sodium excretion quartile | −2.64 | −8.12 | 2.84 | .34 | 0.13 | −6.53 | 6.80 | .97 |
| (B) | ||||||||
| Model 1 | ||||||||
| Estimated 24‐h sodium excretion, 10 mmol/24 h | −0.25 | −2.15 | 1.64 | .79 | −0.004 | −1.80 | 1.79 | 1.00 |
| Estimated sodium excretion quartile | −1.90 | −6.90 | 3.09 | .45 | 1.21 | −3.68 | 6.10 | .62 |
| Model 2 | ||||||||
| Estimated 24‐h sodium excretion, 10 mmol/24 h | −0.80 | −2.57 | 0.97 | .37 | 0.13 | −1.70 | 1.97 | .89 |
| Estimated sodium excretion quartile | −3.02 | −7.65 | 1.62 | .20 | 1.61 | −3.38 | 6.60 | .52 |
| Model 3 | ||||||||
| Estimated 24‐h sodium excretion, 10 mmol/24 h | −0.67 | −2.48 | 1.15 | .46 | 0.42 | −1.46 | 2.29 | .66 |
| Estimated sodium excretion quartile | −2.71 | −7.37 | 1.96 | .25 | 2.08 | −2.94 | 7.09 | .41 |
| Model 4 | ||||||||
| Estimated 24‐h sodium excretion, 10 mmol/24 h | −0.67 | −2.50 | 1.16 | .47 | 0.42 | −1.47 | 2.31 | .66 |
| Estimated sodium excretion quartile | −2.73 | −7.45 | 2.00 | .25 | 2.05 | −3.03 | 7.12 | .42 |
| Model 5 | ||||||||
| Estimated 24‐h sodium excretion, 10 mmol/24 h | −0.82 | −2.70 | 1.06 | .39 | 0.11 | −1.86 | 2.09 | .91 |
| Estimated sodium excretion quartile | −3.18 | −8.03 | 1.67 | .20 | 1.19 | −4.24 | 6.61 | .66 |
| Model 6 | ||||||||
| Estimated 24‐h sodium excretion, 10 mmol/24 h | −0.83 | −2.73 | 1.06 | .38 | 0.05 | −1.97 | 2.06 | .96 |
| Estimated sodium excretion quartile | −3.19 | −8.07 | 1.70 | .20 | 1.07 | −4.43 | 6.57 | .70 |
| Model 7 | ||||||||
| Estimated 24‐h sodium excretion, 10 mmol/24 h | −0.61 | −2.57 | 1.35 | .54 | 0.04 | −2.05 | 2.12 | .97 |
| Estimated sodium excretion quartile | −2.71 | −7.74 | 2.32 | .29 | 0.88 | −4.75 | 6.52 | .75 |
Estimation of 24‐h sodium excretion was based on the Tanaka formula for spot urines.
Model 1: crude.
Model 2: adjusted for baseline systolic blood pressure (BP).
Model 3: adjusted for baseline systolic BP, age, and sex.
Model 4: adjusted for baseline systolic BP, age, sex, and race.
Model 5: adjusted for baseline systolic BP, age, sex, race, and body mass index (BMI).
Model 6: adjusted for baseline systolic BP, age, sex, race, BMI, and baseline estimated glomerular filtration ratio (eGFR).
Model 7: adjusted for baseline systolic BP, age, sex, race, BMI, baseline eGFR, and baseline antihypertensive drug use.
Abbreviations: CI, confidence interval.