Table 5.

Hazard ratios for the primary outcomes based on the 2 average measurements of the mean 24-hour urinary sodium and protein excretion

Models	24-hour urine protein and sodium excretion category
	Proteinuria <0.5 g/d Urine sodium <3.4 g/d		Proteinuria <0.5 g/d Urine sodium ≥3.4 g/d		Proteinuria ≥0.5 g/d Urine sodium <3.4 g/d		Proteinuria ≥0.5 g/d Urine sodium ≥3.4 g/d
	HR (95% CI)	P value	HR (95% CI)	P value	HR (95% CI)	P value	HR (95% CI)	P value
Sensitivity Analysisa
Model 1	Reference		0.58 (0.17–1.99)	0.386	6.77 (2.84–16.13)	<0.001	10.47 (4.26–25.70)	<0.001
Model 2	Reference		0.84 (0.23–3.03)	0.784	4.95 (2.10–11.66)	<0.001	12.51 (4.89–32.00)	<0.001
Model 3	Reference		0.72 (0.20–2.55)	0.606	4.77 (2.00–11.38)	<0.001	12.60 (4.91–32.34)	<0.001

BMI, body mass index; CCB, calcium channel blocker; CCI, charlson comorbidity index; CI, confidence interval; CKD, chronic kidney disease; DPI, dietary protein intake; eGFR, estimated glomerular filtration rate; HR, hazard ratio; RAAS, renin-angiotensin-aldosterone system.

Model 1: age, sex, BMI, smoking history, primary renal disease, CCI, DPI, and hospital center.

Model 2: model 1 plus systolic blood pressure and laboratory parameters, including hemoglobin, phosphate, eGFR, albumin, total cholesterol, natural log of average 24-hour urine potassium, and natural log of average 24-hour urine creatinine.

Model 3: model 2 plus medications, including RAAS blockers, CCB, and diuretics.

The primary outcome was defined as CKD progression, which was defined as the first occurrence of a 50% decline in eGFR from the baseline value, or the onset of kidney failure with replacement therapy, and the analysis was performed using a cause-specific model by censoring the death event that occurred before reaching the kidney outcome.

^aSensitivity analysis: Mean urine sodium excretion was calculated using the average urine sodium excretion at baseline and 3 years later.