Economic burden of comorbid chronic kidney disease and diabetes

Figures & data

Table 1. Baseline demographic characteristics by chronic kidney disease stage.

	Chronic kidney disease stage^a
	Stage 5	Stage 4	Stage 3B	Stage 3A	Stage 2	Stage 1	All CKD stages^b
Population Size	269 (0.2%)	898 (0.7%)	3,217 (2.5%)	13,377 (10.3%)	47,816 (36.8%)	64,521 (49.6%)	130,098 (100%)
Sex - Female	124 (46.1%)	483 (53.8%)	1,754 (54.5%)	6,889 (51.5%)	22,322 (46.7%)	33,466 (51.9%)	65,038 (50.0%)
Age in years, mean (SD)	61.5 (12.9)	65.52 (12.9)	66.46 (11.9)	60.91 (10.5)	56.88 (9.4)	49.75 (10.2)	54.06 (11.1)
Region
Northeast	6 (2.2%)	33 (3. 7%)	127 (4.0%)	822 (6.1%)	4,873 (10.2%)	7,499 (11.6%)	13,360 (10.3%)
North Central	143 (53.2%)	483 (53.8%)	1,835 (57.0%)	4,780 (35.7%)	12,611 (26.4%)	8,130 (12.6%)	27,982 (21.5%)
South	94 (34.9%)	306 (34.1%)	981 (30.5%)	6,163 (46.1%)	24,713 (51.7%)	40,456 (62.7%)	72,713 (55.9%)
West	26 (9.7%)	76 (8.5%)	272 (8.5%)	1,609 (12.0%)	5,598 (11.7%)	8,424 (13.1%)	16,005 (12.3%)
Unknown	0 (0.0%)	0 (0.0%)	2 (0.06%)	3 (0.02%)	21 (0.04%)	12 (0.02%)	38 (0.03%)
Pay type
Medicare	117 (43.5%)	439 (48.9%)	1,630 (50. 7%)	3,734 (27.9%)	6,846 (14.3%)	1,862 (2.9%)	14,628 (11.2%)
Commercial	152 (56.5%)	459 (51.1%)	1,587 (49.3%)	9,643 (72.1%)	40,970 (85.7%)	62,659 (97.1%)	115,470 (88.8%)
Plan type
Not Reported	1 (0.4%)	0 (0.0%)	9 (0.3%)	41 (0.3%)	163 (0.3%)	249 (0.4%)	463 (0.4%)
Comprehensive	118 (43.9%)	374 (41.7%)	1,413 (43.9%)	3,229 (24.1%)	6,635 (13.9%)	2,434 (3.8%)	14,203 (10.9%)
EPO	0 (0.0%)	7 (0.8%)	17 (0.5%)	190 (1.4%)	1,467 (3.1%)	2,691 (4.2%)	4,372 (3.4%)
HMO	33 (12.3%)	59 (6.6%)	256 (8.0%)	2,000 (15.0%)	7,960 (16.7%)	11,995 (18.6%)	22,303 (17.1%)
POS	6 (2.2%)	14 (1.6%)	59 (1.8%)	256 (1.9%)	2,005 (4.2%)	2,956 (4.6%)	5,296 (4.1%)
PPO	108 (40.2%)	435 (48.4%)	1,427 (44.4%)	7,476 (55.9%)	28,322 (59.2%)	42,769 (66.3%)	80,537 (61.9%)
POS with capitation	0 (0.0%)	1 (0.1%)	3 (0.1%)	22 (0.2%)	141 (0.3%)	222 (0.3%)	389 (0.3%)
CDHP	3 (1.1%)	6 (0.7%)	28 (0.9%)	127 (1.0%)	827 (1.7%)	825 (1.3%)	1,816 (1.4%)
HDHP	0 (0.0%)	2 (0.2%)	5 (0.2%)	36 (0.3%)	296 (0.6%)	380 (0.6%)	719 (0.6%)
Dialysis procedure code during baseline period	189 (70.3%)	129 (14.4%)	57 (1.8%)	39 (0.3%)	27 (0.1%)	23 (0.04%)	464 (0.4%)
Charlson Comorbidity Index, mean (SD)	4.21 (2.39)	3.32 (2.42)	2.66 (2.22)	1.77 (1.85)	1.33 (1.49)	1.19 (1.34)	1.36 (1.53)

^a Data are n (%), unless otherwise specified.

^b Distributional Chi-squared tests were significant at p < .001 across all variables; CCI was significantly at p < .001 using a t-test when comparing stage 1 to stages 2–5.

CDHP: Consumer Directed Health Plan; EPO: Exclusive Provider Organization; HMO: Health Maintenance Organization; HDHP: High-Deductible Health Plan; POS: Point-of-Service; PPO: Preferred Provider Organization.

Table 2. Adjusted annual utilization estimates by chronic kidney disease stage.

		Chronic kidney disease stage
		Stage 5 (n = 269)	Stage 4 (n = 898)	Stage 3B (n = 3,217)	Stage 3A (n = 13,377)	Stage 2 (n = 47,816)	Stage 1 (n = 64,521)
Diabetes related medications^a
Excluding refills		0.50* (0.43–0.57)	0.73* (0.68–0.79)	0.86* (0.83–0.89)	0.88* (0.86–0.89)	0.85* (0.84–0.86)	referent group
Including refills		0.86 (0.70–1.05)	1.03 (0.93–1.15)	1.03 (0.97–1.10)	0.93* (0.90–0.96)	0.90* (0.87–0.92)	referent group
All other medications^a
Excluding refills		1.35* (1.23–1.47)	1.22* (1.16–1.28)	1.12* (1.09–1.15)	1.04* (1.03–1.06)	1.02* (1.01–1.03)	referent group
Including refills		1.35* (1.21–1.50)	1.30* (1.22–1.37)	1.19* (1.14–1.23)	1.10* (1.08–1.12)	1.05* (1.04–1.07)	referent group
Outpatient visits^a
Diabetes-specific		1.63* (1.39–1.89)	1.37* (1.26–1.49)	1.19* (1.13–1.25)	1.01 (0.98–1.03)	0.93* (0.92–0.95)	referent group
All-cause		4.07* (3.66–4.53)	1.59* (1.47–1.73)	1.16* (1.12–1.20)	1.06* (1.04–1.07)	1.00 (0.99–1.02)	referent group
Emergency department visits^a
Diabetes-specific		2.36* (1.65–3.37)	2.09* (1.67–2.62)	1.49* (1.25–1.77)	1.36* (1.22–1.52)	0.95 (0.89–1.01)	referent group
All-cause		2.67* (2.20–3.24)	2.19* (1.84–2.59)	1.50* (1.36–1.66)	1.25* (1.17–1.33)	0.99 (0.95–1.03)	referent group
Inpatient visits^a
Diabetes-specific		3.83* (2.91–5.03)	2.65* (2.23–3.14)	1.59* (1.41–1.80)	1.32* (1.22–1.43)	0.94* (0.88–0.99)	referent group
All-cause		1.58* (1.38–1.79)	1.11* (1.03–1.19)	0.99 (0.96–1.03)	0.98* (0.97–0.99)	0.99 (0.99–1.00)	referent group

* Statistically significant at p < .05.

^a Marginal effects are incidence rate ratios (IRR) and 95% confidence intervals from negative binomial regression models adjusting for baseline Charlson comorbidity index, insurance type (commercial, Medicare), region, age, plan type (PPO, HMO, etc.), and all prescribed medications.

Table 3. Adjusted annual expenditure estimates by chronic kidney disease stage.

	Chronic kidney disease stage
	Stage 5 (n = 269)	Stage 4 (n = 898)	Stage 3B (n = 3,217)	Stage 3A (n = 13,377)	Stage 2 (n = 47,816)	Stage 1 (n = 64,521)
Marginal healthcare expenditures in 2015 US Dollars (paid claims)^a
Diabetes-related	$5,648* ($4,533–$6,763)	$3,217* ($2,535–$3,899)	$1,314* ($854–$1,774)	$741* ($453–$1,029)	−$170 (−$383– −$42)	referent group
All-cause	$20,210* $17,979–$22,440)	$6,949* ($5,466–$8,432)	$2,632* ($1,647–$3,619)	$1,732* ($1,109–$2,356)	−$226 (−$647–$194)	referent group

* Statistically significant at p-value <.05.

^a Marginal effects (95% confidence intervals) from generalized linear model with Poisson family and log link (tested using modified park test) after adjusting for baseline Charlson comorbidity index, insurance type (commercial, Medicare), region, age, plan type (PPO, HMO, etc.), and all prescribed medications.

Figure 1. Adjusted 12-month follow-up all-cause and diabetes-specific medical expenditures by CKD stage.

Figure 2. Adjusted 12-month follow-up all-cause and diabetes-specific pharmacy expenditures by CKD stage.