Table 1.

Demographic & clinical characteristics of study sample

Variable	Total cohort (n = 70,114)	Survived < 270 days (n = 17,177)	Survived ≥ 270 days (n = 52,937)	± p-value
Comorbidity index scores
*Original Liu Comorbidity Index Score (mean ± st. dev.)	Cannot be calculated	Cannot be calculated	7.35 ± 3.99	N/A
**Modified Liu Comorbidity Index Score (mean ± st. dev.)	6.60 ± 3.75	7.30 ± 4.16	6.37 ± 3.58	<0.0001
Demographic and clinical characteristics
Age (years) (mean ± st. dev.)	61.5 ± 15.4	62.3 ± 16.4	61.2 ± 15.1	<0.0001
Gender (% women)	56.2%	53.8%	57.0%	<0.0001
Race/Ethnicity				<0.0001
Black	40.3%	39.0%	40.8%
Hispanic	18.0%	15.8%	18.8%
Other	6.0%	5.2%	6.2%
White	35.7%	40.0%	34.3%
Employed	2.5%	3.2%	2.3%	<0.0001
Tobacco use	6.4%	6.4%	6.4%	0.7830
Substance abuse	2.9%	2.9%	2.8%	0.7413
Unable to ambulate	5.8%	7.9%	5.2%	<0.0001
Unable to transfer	2.1%	3.3%	1.8%	<0.0001
Home dialysis	4.9%	4.6%	5.0%	0.0589
Body Mass Index				<0.0001
<20	10.4%	12.5%	9.7%
≥20 to < 24.99	30.0%	31.5%	29.5%
≥25 to <29.99	26.9%	26.2%	27.1%
≥30	32.8%	29.9%	33.7%
Hemoglobin >11 mg/dL	25.0%	24.8%	25.0%	0.4501
Primary renal diagnosis:				<0.0001
Diabetes mellitus	53.0%	49.3%	54.2%
Hypertension	25.7%	26.5%	25.4%
Immune	7.4%	7.5%	7.3%
Other	14.0%	16.8%	13.1%
¶Diabetes mellitus	62.8%	60.3%	63.7%	<0.0001
Congestive heart failure	34.2%	37.1%	33.3%	<0.0001
Coronary artery disease	25.4%	27.2%	24.8%	<0.0001
Cerebrovascular disease	11.1%	12.5%	10.6%	<0.0001
Peripheral vascular disease	14.8%	16.6%	14.3%	<0.001

*Original Liu Index captures comorbidity data from days 91–270 after dialysis initiation.

** Modified Liu Index _1–90 captures comorbidity data from days 1–90 after dialysis initiation.

± p-value for bivariate test statistic by survival group.

¶ Diabetes considered present if either noted as the primary cause for renal failure or as a comorbidity in claims data.