Table 2. Influence of Scheduled Dialysis on Health Care Utilization and Costs^a.

Outcome	Emergency-Only Dialysis (n = 76)			Scheduled Dialysis (n = 105)			Difference-in-Differences (95% CI)c	P Value
	Baseline	Follow-up	Net Changeb	Baseline	Follow-up	Net Changeb
Unadjusted Average Utilization Rates
ED visits per mo	4.0	4.5	+0.6	6.3	0.2	−6.1	−6.7 (−7.3 to −6.0)	<.001
Dialysis ED visits per mo	3.5	4.3	+0.8	5.6	0.0	−5.5	−6.3 (−7.0 to −5.7)	<.001
Non-dialysis ED visits per mo	0.5	0.3	−0.2	0.8	0.2	−0.6	−0.4 (−0.6 to −0.2)	<.001
Hospitalizations per 6 mo	3.0	2.4	−0.5	3.0	1.0	−2.0	−1.5 (−2.3 to −0.8)	<.001
Hospital d per 6 mo	22.4	24.1	+1.7	14.8	6.4	−8.4	−10.1 (−17.7 to −2.5)	.009
Adjusted Average Utilization Ratesd
ED visits per mo	5.0	6.1	+1.1	5.3	0.2	−5.2	−6.2 (−7.0 to −5.4)	<.001
Dialysis ED visits per mo	4.4	5.6	+1.2	4.8	0.0	−4.7	−6.0 (−6.7 to −5.2)	<.001
Non-dialysis ED visits per mo	0.6	0.4	−0.2	0.6	0.1	−0.5	−0.2 (−0.4 to −0.04)	.02
Hospitalizations per 6 mo	2.9	2.3	−0.5	3.1	1.0	−2.1	−1.6 (−2.3 to −0.8)	<.001
Hospital d per 6 mo	19.2e	20.0	+0.8	16.7e	7.6	−9.2	−9.9 (−17.1 to −2.7)	.007
Costs: Best-Case Scenariof
Unadjusted costs PPPM, $	8317	9581	+1264	11 223	6288	−4935	−6199 (−8677 to −3721)	<.001
Adjusted costs PPPM, $d	8691	10 146	+1455	10 802	6090	−4711	−6166 (−8753 to −3579)	<.001
Costs: Worst-Case Scenariog
Unadjusted costs PPPM, $	8317	9581	+1264	11 223	6697	−4525	−5790 (−8246 to −3333)	<.001
Adjusted costs PPPM, $d	8686	10 138	+1452	10 806	6490	−4316	−5768 (−8332 to −3204)	<.001

Abbreviations: ED, emergency department; PPPM, per person per month.

^aAll utilization and costs were estimated per individual. We estimated costs per person per month by applying average national Medicare reimbursement rates for the following billed services to monthly event rates estimated for each individual: (1) emergency care and observation visits, (2) hospitalizations, (3) outpatient hemodialysis, (4) vascular access placement and/or complications. For further details, refer to the eMethods in the Supplement.

^bValues may not equal the exact difference in baseline and follow-up values due to rounding.

^cDifference-in-differences were estimated as the difference in net change in scheduled dialysis group minus net change in emergency-only group.

^dAdjusted for propensity score (age, sex, dialysis vintage, baseline ED visits, baseline hospital days, baseline serum albumin, baseline vascular access type).

^eIn a sensitivity analysis, we omitted extreme outliers defined as individuals in the highest 99th percentile (n = 2). At baseline, the emergency-only group had an adjusted rate of 16.9 vs 15.9 hospital days per 6 mo in the scheduled group. At follow-up, the emergency-only group had an adjusted rate of 18.9 vs 7.1 hospital days per 6 mo in the scheduled group. The adjusted difference-in-differences estimate was −10.7 hospital days per 6 mo (95% CI −17.9 to −3.5, P = .003).

^fTo estimate average health care costs PPPM in a best-case scenario with low vascular access complication rates, we applied vascular access complication rates observed in the late dialysis initiation arm of a previously published randomized controlled trial of early vs late dialysis initiation.²⁸ For further details, refer to the eMethods in the Supplement.

^gTo estimate average health care costs PPPM in a worst-case scenario with high vascular access complication rates, we applied vascular access complication rates observed during the first year after initial arteriovenous fistula placement in an observational study of older Medicare beneficiaries.²⁹ For further details, refer to the eMethods in the Supplement.