Table 4.

Hazard ratios for primary outcome based on baseline 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
Model 1	Reference		0.69 (0.38–1.24)	0.213	4.22 (2.77–6.42)	<0.001	5.82 (3.82–8.88)	<0.001
Model 2	Reference		1.19 (0.64–2.20)	0.577	2.33 (1.51–3.59)	<0.001	5.94 (3.73–9.48)	<0.001
Model 3	Reference		1.11 (0.60–2.07)	0.730	2.32 (1.50–3.58)	<0.001	5.71 (3.58–9.11)	<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 24-hour urine potassium, and natural log 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 analysis was performed using a cause-specific model by censoring the death event that occurred before reaching the kidney outcome.