Healthcare resource utilization and costs among patients with psoriasis treated with ixekizumab or adalimumab over 2 years of follow-up in real-world settings

Figures & data

Table 1. Baseline demographic and clinical characteristics for 24 months of follow-up (weighted and unweighted results).

Variables	Before weighting			After weighting
Demographic characteristics	IXE	ADA	Std. Diff	IXE	ADA	Std. Diff
Age (mean, SD)	48.4 (11.0)	46.4 (12.1)	0.173	46.3 (11.5)	46.7 (12.1)	0.034
Male (%)	55.4%	56.6%	0.024	57.9%	56.3%	0.031
Primary payer (%)	95.6%	96.7%	0.057	96.6%	96.5%	0.000
Insurance plan type (%)			0.183			0.089
Comprehensive/indemnity (%)	2.1%	4.9%		5.8%	4.6%
EPO/PPO (%)	61.7%	56.5%		54.5%	57.2%
POS/POS with capitation (%)	5.3%	4.4%		4.2%	4.5%
HMO (%)	9.9%	10.4%		10.1%	10.3%
CDHP, HDHP (%)	20.2%	22.6%		24.6%	22.3%
Other/Unknown (%)	0.8%	1.2%		0.8%	1.2%
Geographic region (%)			0.136			0.122
Northeast	18.7%	16.6%		19.7%	16.9%
North central	19.2%	23.1%		20.5%	22.6%
South	49.9%	48.2%		48.9%	48.3%
West	12.2%	11.7%		10.8%	11.8%
Unknown	0.0%	0.4%		0.0%	0.4%
Clinical characteristics
Pre-period DCCI (mean, SD)	0.3 (0.9)	0.3 (0.8)	0.07	0.3 (0.9)	0.3 (0.8)	0.022
Pre-period comorbid conditions (%)
Anxiety	5.9%	8.1%	0.088	8.3%	7.8%	0.016
Cerebrovascular disease	0.8%	0.9%	0.011	0.9%	1.0%	0.005
Coronary heart disease	3.4%	2.5%	0.053	2.0%	2.6%	0.042
Depression	5.7%	6.6%	0.04	5.5%	6.5%	0.043
Diabetes	14.9%	11.4%	0.106	11.0%	11.8%	0.027
Hyperlipidemia	21.5%	19.2%	0.057	21.2%	19.6%	0.041
Hypertension	25.5%	24.2%	0.028	24.7%	24.5%	0.006
Obesity	17.1%	13.6%	0.095	13.8%	14.0%	0.006
Osteoarthritis	6.1%	6.0%	0.005	7.2%	6.0%	0.045
Other autoimmune disorders	2.3%	1.8%	0.034	2.0%	1.9%	0.007
Sleep apnea	9.7%	6.2%	0.129	5.8%	6.6%	0.033
Pre-period treatments
Any biologics (biologic-experienced) (%)	55.6%	28.6%	0.567	29.2%	32.1%	0.064
Any systemic agents/targeted oral therapies (%)	41.1%	40.1%	0.019	36.1%	40.2%	0.083
Any topical agents (%)	61.1%	58.8%	0.046	55.2%	59.1%	0.079
Phototherapy or laser treatments (%)	4.2%	3.5%	0.04	3.0%	3.5%	0.028
Pre-period all-cause healthcare costs (mean, SD)	$3,525 ($3,730)	$1,763 ($2,932)	0.525	$2,186 ($3,723)	$1,934 ($3,254)	0.072
Pre-period psoriasis-related healthcare costs (mean, SD)	$2,563 ($2,425)	$1,061 ($1,506)	0.744	$1,326 ($1,981)	$1,198 ($1,614)	0.071
Pre-period comorbidity-related costs (mean, SD)	$357 ($1,664)	$235 ($1,350)	0.081	$368 ($2,395)	$269 ($1,859)	0.046

Abbreviations. ADA, adalimumab; CDHP, consumer-directed health plan; DCCI, Deyo Charlson comorbidity index; EPO, exclusive provider organization; HDHP, high deductible health plan; HMO, health maintenance organization; IXE, ixekizumab; POS, point of service; PPO, preferred provider organization; SD, standard deviation; Std. Diff, standardized difference.

IXE (N = 475); ADA (N = 3,159).

Table 2. Healthcare resource utilization (all-cause and psoriasis-related healthcare utilization) weighted results during 24 months of follow-up.

	All-cause healthcare utilization, PPPM			Psoriasis-related healthcare utilization, PPPM
	IXE	ADA	p-value	IXE	ADA	p-value
Inpatient
Patients with an admission (%)	14.9%	11.0%	0.012	0.0%	0.1%	N/A
Number of inpatient admissions (mean, SD)	0.01 (0.03)	0.01 (0.03)	0.069	0	0.0001(0.0044)	0.573
Length of stay (in days) per admission (mean, SD)	6.6 (11.0)	4.1 (4.9)	0.004	N/A	4.4 (4.4)	N/A
Outpatient
Patients with an ER visit (%)	31.5%	30.4%	0.630	1.2%	2.0%	0.207
Number of ER visits (mean, SD)	0.02 (0.09)	0.02 (0.06)	0.961	0.001(0.005)	0.001 (0.008)	0.123
Outpatient office visits
Patients with an office visit (%)	99.6%	99.8%	N/A	97.9%	96.9%	0.209
Number of office visits (mean, SD)	0.7 (0.5)	0.7 (0.5)	0.526	0.2 (0.1)	0.2 (0.1)	0.787
Other outpatient services
Patients with other outpatient services (%)	99.1%	99.3%	N/A	82.7%	80.1%	0.176
Number of other outpatient services (mean, SD)	1.0 (1.1)	1.0 (1.1)	0.485	0.1 (0.1)	0.1 (0.2)	0.982
Outpatient pharmacy
Patients with a prescription (%)	100.0%	100.0%	1.000	100.0%	100.0%	1.000
Number of prescriptions (mean, SD)	2.4 (1.9)	2.4 (1.9)	0.722	0.8 (0.4)	0.8 (0.4)	<0.001

Abbreviations. ADA, adalimumab; IXE, ixekizumab; PPPM, per patient per month; SD, standard deviation.

IXE (N = 475); ADA (N = 3,159).

Figure 1. Weighted all-cause and psoriasis-related healthcare costs (PPPM): Without ICER adjustment, 24-month follow-up (IXE vs. ADA). (a) All-cause healthcare costs (without ICER adjustment). (b) Psoriasis-related healthcare costs (without ICER adjustment).

Abbreviations. ADA, adalimumab; ICER, Institute for Clinical and Economic Review; IXE, ixekizumab; PPPM, per patient per month; SD, standard deviation.

Weighted two-tailed t-test, **p ≤ 0.001, *p < 0.01, ns: p > 0.1.

Note: Data are represented as mean with SD.

Figure 2. Weighted total healthcare costs (PPPM): Without ICER adjustment and with ICER adjustment, 24-month follow-up (IXE vs. ADA).

Abbreviations. ADA, adalimumab; ICER, Institute for Clinical and Economic Review; IXE, ixekizumab; PPPM, per patient per month; SD, standard deviation.

Weighted two-tailed t-test, **p < 0.001, *p < 0.01, ns: p > 0.1.

Note: Data are represented as mean with SD.

Figure 3. Weighted index drug costs, 24-month follow-up (IXE vs. ADA).

Abbreviations. ADA, adalimumab; ICER, Institute for Clinical and Economic Review; IXE, ixekizumab; SD, standard deviation.

Weighted two-tailed t-test, **p < 0.001, *p < 0.01, ns: p > 0.1.

Note: Data are represented as mean with SD.