Longer serum phosphorus time in range associated with lower mortality risk among peritoneal dialysis patients: a multicenter retrospective cohort study

Table 2 Association between serum phosphorus time in range in the first PD year and clinical outcomes by Cox regression model

Serum phosphorus time in range in the first PD year	N	Events, N (%)	Crude Model ^a		Adjusted Model ^b
Serum phosphorus time in range in the first PD year	N	Events, N (%)	HR (95%CI)	P-Value	aHR (95%CI)	P-Value
All-cause mortality
Continuous, per 3 months	1915	249 (13.0)	0.82 (0.74, 0.90)	< 0.001	0.83 (0.75, 0.92)	< 0.001
Categories
0 month	319	64 (20.1)	Ref.		Ref.
≤ 6 months (median)	884	112 (12.7)	0.59 (0.43, 0.80)	< 0.001	0.53 (0.39, 0.73)	< 0.001
> 6 months	712	73 (10.3)	0.46 (0.33, 0.65)	< 0.001	0.50 (0.35, 0.72)	< 0.001
CV mortality
Continuous, per 3 months	1915	172 (9.0)	0.83 (0.74, 0.93)	0.002	0.87 (0.77, 0.99)	0.029
Categories
0 month	319	42 (13.2)	Ref.		Ref.
≤ 6 months (median)	884	79 (8.9)	0.64 (0.44, 0.93)	0.018	0.60 (0.41, 0.89)	0.011
> 6 months	712	51 (7.2)	0.49 (0.33, 0.74)	< 0.001	0.58 (0.38, 0.90)	0.016
PD withdrawal ^c
Continuous, per 3 months	1915	527 (27.5)	0.86 (0.81, 0.92)	< 0.001	0.89 (0.83, 0.95)	< 0.001
Categories
0 month	319	119 (37.3)	Ref.		Ref.
≤ 6 months (median)	884	247 (27.9)	0.70 (0.56, 0.87)	0.001	0.71 (0.57, 0.89)	0.003
> 6 months	712	161 (22.6)	0.55 (0.43, 0.70)	< 0.001	0.62 (0.49, 0.80)	< 0.001

Notes: ^a Crude Model: We did not adjust other covariates. ^b Adjusted Model: adjusted for age, gender, BMI, smoking, alcohol drinking, diabetes history, CVD history, baseline phosphorus, phosphate-binding and RASi medications, RKF loss (with or without, in the first year), and the mean values of SBP, dialysate GLUC, UF volume, total weekly Kt/V score, LN of iPTH, serum albumin, serum creatinine and blood HGB in the first year after PD initiation. ^c PD withdrawal was defined as death and transfer to HD.
Abbreviations: HR, hazards ratio; aHR, adjusted hazards ratio; CI, confidence interval; Ref, reference; CV, cardiovascular; BMI, body mass index; CVD, cardiovascular disease; RASi: renin-angiotensin system inhibitor; RKF, residual kidney function; SBP, systolic blood pressure; GLUC, dialysate glucose concentration; UF, ultrafiltration; LN, natural logarithm; iPTH, intact parathyroid hormone; HGB, hemoglobin; PD, peritoneal dialysis; HD, hemodialysis.

ISSN: 1471-2369