Blood urea nitrogen is independently associated with renal outcomes in Japanese patients with stage 3–5 chronic kidney disease: a prospective observational study

Table 3 Hazard ratios for ESRD associated with BUN and cSosm levels

		No. of events	^aIncidence rate	Model 1			P for trend	Model 2			P for trend	Model 3			P for trend
		No. of events	^aIncidence rate	HR	95% CI	P	P for trend	HR	95% CI	P	P for trend	HR	95% CI	P	P for trend
BUN (mg/dL)
8–23	Q1 (n = 128)	15	3.61	reference			< 0.01	reference			< 0.01	reference			0.03
24–30	Q2 (n = 104)	29	8.35	2.72	1.46–5.11	< 0.01		2.25	1.20–4.24	0.01		1.45	0.71–2.97	0.31
31–41	Q3 (n = 114)	58	21.20	7.24	4.06–12.92	< 0.01		6.74	3.79–11.98	< 0.01		1.75	0.83–3.71	0.14
42–94	Q4 (n = 113)	71	37.62	14.59	8.18–26.03	< 0.01		14.64	8.24–26.01	< 0.01		2.42	1.03–5.67	0.04
cSosm (mOsm/kg)
277–293	Q1 (n = 115)	21	5.42	reference			< 0.01	reference			< 0.01	reference			0.07
293–297	Q2 (n = 115)	33	10.87	2.21	1.28–3.85	< 0.01		1.79	1.03–3.12	0.04		1.31	0.73–2.34	0.36
297–301	Q3 (n = 115)	43	13.65	2.89	1.70–4.92	< 0.01		2.12	1.24–3.61	< 0.01		0.96	0.55–1.70	0.90
301–325	Q4 (n = 114)	76	34.72	7.56	4.61–12.38	< 0.01		6.06	3.69–9.96	< 0.01		1.64	0.95–2.82	0.07

Model 1: adjusted for age and sex
Model 2: model 1 plus adjusted for diabetes mellitus, smoking, systolic blood pressure, and dyslipidemia
Model 3: model 2 plus adjusted for use of immunosuppressants, and diuretics; daily proteinuria; hemoglobin; eGFR; serum phosphorus; and serum albumin
ESRD end-stage renal disease, BUN blood urea nitrogen, cSosm calculated serum osmolality, HR hazard ratio, CI confidence interval, eGFR estimated glomerular filtration rate. ^aIncidence rate per 100 person-years

ISSN: 1471-2369