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

Table 2 Hazard ratios for composite of ESRD or death 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)	20	4.76	reference			< 0.01	reference			< 0.01	reference			< 0.01
24–30	Q2 (n = 104)	33	9.47	2.07	1.18–3.64	0.01		1.81	1.03–3.18	0.04		1.36	0.72–2.58	0.34
31–41	Q3 (n = 114)	65	23.56	5.46	3.27–9.11	< 0.01		5.34	3.21–8.87	< 0.01		1.87	0.95–3.66	0.07
42–94	Q4 (n = 113)	92	47.06	11.65	7.06–19.21	< 0.01		11.71	7.12–19.25	< 0.01		2.66	1.23–5.76	0.01
cSosm (mOsm/kg)
277–293	Q1 (n = 115)	29	7.44	reference			< 0.01	reference			< 0.01	reference			0.39
293–297	Q2 (n = 115)	41	13.45	1.86	1.15–3.00	0.01		1.60	0.99–2.60	0.05		1.13	0.69–1.87	0.62
297–301	Q3 (n = 115)	52	16.32	2.23	1.40–3.54	< 0.01		1.82	1.14–2.90	0.01		0.95	0.58–1.55	0.85
301–325	Q4 (n = 114)	88	39.18	5.58	3.64–8.56	< 0.01		4.79	3.11–7.38	< 0.01		1.26	0.78–2.03	0.35

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; C-reactive protein; body mass index; 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