Background
 ■ Psoriasis (PsO) is an inflammatory skin disease associated with a variety of 

psychiatric comorbidities such as anxiety and depression. 
 ■ Psychiatric comorbidities are associated with poor treatment adherence in PsO 

patients, resulting in worse quality of life and increased economic burden.1

Objectives
 ■ To estimate the healthcare utilization, direct costs, and indirect costs due to 

absenteeism or short-term disability associated with treated comorbid anxiety 
and/or depression among moderate-to-severe PsO patients in the US

Methods
Study Design and Data Sources

 ■ This was a retrospective cohort study of a commercially-insured population in 
the US.

 ■ Data were extracted from the Truven Health MarketScan® Commercial Claims 
and Encounters (Commercial) database and Health and Productivity (HPM) 
databases. 

 — The Commercial database provides detailed outcome measures including 
resource utilization and associated costs for healthcare services performed 
in inpatient and outpatient setting.

 — The HPM database contains workplan absenteeism and short-term disability 
data for a subset of enrollees in the Commercial databases. 

Study Cohorts
 ■ Moderate to severe PsO: Adults with ≥1 PsO diagnosis plus ≥1 prescribed 

systemic or biologic PsO medication (proxy for moderate-to-severe PsO) from 
1/1/2014 to 12/31/2014

 — PsO with treated anxiety/depression: Patients with ≥1 diagnosis for 
anxiety and/or depression plus a prescription for anxiolytics, antipsychotics, 
or antidepressants filled within ±30 days of diagnosis

 — PsO without treated anxiety/depression (controls): Patients with neither 
anxiety/depression diagnosis nor prescription for anxiolytics, antipsychotics, 
or antidepressants 

 — Controls were randomly selected and matched 1:1 with patients with treated 
anxiety/depression on age, gender, health plan type, and region using 
the exact attribute matching method, to ensure comparability and reduce 
potential confounding biases.

Figure 1. Patient Selection

Patients ≥18 years old as of 1/1/2014
(N=27,706,785)

Continuous enrollment from 1/1/2014 to 12/31/2015
(N=11,223,477; 40.5%)

≥1 medical claim with diagnosis of PsO AND ≥1 non-topical systemic PsO
medication from 1/1/2014 to 12/31/2014

(N=17,955; 0.2%)

≥1 claim for diagnosis of anixety or 
depression plus a prescription of 

antianxiety agents, antipsychotics, or 
antidepressants �lled within ± 30 days of the 

diagnosis during 1/1/2014 to 12/31/2014

No claim for diagnosis of anxiety or
depression, prescription of antianxiety agents,

antipsychotics, or antidepressants during
1/1/2014 to 12/31/2014

(N=11,226)

Matched* PsO with
treated anxiety/depression

(N=2,281)

Matched* PsO without
treated anxiety/depression

(N=2,281)

*The exact attribute matching method was applied to match the moderate to severe PsO patients with vs without treated anxiety/
depression on a 1:1 ratio based on the following variables: age, gender, health plan type, residence region

Study Measures
 ■ All-cause healthcare costs were defined as the sum of plan–paid and patient-

paid costs, associated with any conditions incurred from inpatient admissions, 
emergency room visits, outpatient services, and outpatient pharmacy prescriptions.

 ■ PsO-related costs included medical costs associated with a PsO diagnosis and 
costs for PsO-related biologics and other systemic medications. 

 ■ All-cause and PsO-related healthcare costs were compared between those with 
treated anxiety/depression and matched controls; in addition, costs due to both 
anxiety and depression, anxiety only, or depression only were also compared 
between the two cohorts. 

 ■ Lost time from short term disability was reported and indirect costs were 
estimated by multiplying lost days by 70%2 of the 2015 Bureau of Labor (BLS) 
age-gender stratified daily wage rate for patients whose data could be linked 
with the HPM database.

Statistical Analysis
 ■ The statistical significance of differences between the two cohorts was assessed 

using the t-test for continuous variables and chi-square or Fisher's exact test for 
categorical variables.

 ■ Generalized linear models with gamma distribution were used to estimate the 
incremental total costs attributable to treated anxiety/depression, after adjusting 
for demographic characteristics and comorbid conditions. 

 ■ All statistical analyses were conducted using SAS Enterprise Guide 7  
(SAS Institute Inc., Cary NC).

 ■ A p-value of < 0.05 was defined as statistically significant.

Results
Demographic Characteristics 

 ■ A total of 4,562 commercially insured patients were included; 65% were female 
and the mean (±SD) age was 49 (±11) years (Table 1).

Table 1. Demographic Characteristics of the Study Patients

Total PsO 
N=4,562

Matched PsO with Treated 
Anxiety/Depression 

(n=2,281)

Matched PsO without Treated  
Anxiety/Depression 

(n=2,281)

Age (mean, SD) 48.6 10.5 48.6 10.5 48.6 10.5

18-44 (n, %) 1,452 31.8% 726 31.8% 726 31.8%

45-64 3,110 68.2% 1,555 68.2% 1,555 68.2%

65+ 0 0.0% 0 0.0% 0 0.0%

Gender (n, %)       

Male 1,614 35.4% 807 35.4% 807 35.4%

Female 2,948 64.6% 1,474 64.6% 1,474 64.6%

Region (n, %)       

Northeast 796 17.4% 398 17.4% 398 17.4%

North central 852 18.7% 426 18.7% 426 18.7%

South 2,356 51.6% 1,178 51.6% 1,178 51.6%

West 556 12.2% 278 12.2% 278 12.2%

Unknown 2 0.0% 1 0.0% 1 0.0%

Commercial Plan Type (n, %)       

HMO 418 9.2% 209 9.2% 209 9.2%

PPO 3,022 66.2% 1,511 66.2% 1,511 66.2%

POS 226 5.0% 113 5.0% 113 5.0%

CDHP/HDHP 734 16.1% 365 16.0% 369 16.2%

Others* 146 3.2% 75 3.3% 71 3.1%

Unknown 16 0.4% 8 0.4% 8 0.4%

CDHP: consumer-driven health plan; HDHP: high deductible health plan; HMO: health maintenance organization; PPO: preferred 
provider organization; POS: point-of-service plan 
*Includes Comprehensive/Indemnity, Exclusive Provider Organization, missing or Unknown

Figure 2. Three Most Frequently Occurring Comorbid Conditions and Concomitant 
Medications used Among Study Patients 

39.2%

45.1% 44.4%

54.9%

46.5%

35.9%
33.8% 32.7%

30.3% 30.0% 31.0%

17.7%

0.0%

10.0%

20.0%

30.0%

40.0%

50.0%

60.0%

Psoriatic
Arthritis

Hypertension Hyperlipidemia Opioids Respiratory
Medication

Anticholinergics

Matched PsO with Treated Anxiety/Depression Matched PsO without Treated Anxiety/Depression

§All p<0.01

Clinical Characteristics 
 ■ Compared with controls, PsO patients with treated anxiety/depression had 

significantly higher overall burden of comorbidity, as measured by the  
Quan-Charlson Comorbidity index (all p<0.01).

 ■ The PsO with treated anxiety/depression cohort had a significantly higher 
percentage of patients with hypertension, hyperlipidemia, psoriatic arthritis (all 
p<0.01,) and use of concomitant medications (including opioids) (Figure 2)  than 
the control cohorts. 

All-cause and PsO-related Healthcare Costs 
 ■ On average, patients in the PsO with treated anxiety and/or depression cohort 

incurred $10,419 (p<.01) higher unadjusted and $6,343 (p<.01) higher adjusted 
annual all-cause healthcare costs than matched PsO controls; 88% of the 
difference was due to medical services and 12% due to prescriptions (Table 2). 

 — The all-cause difference was driven by a higher percentage of patients in 
the PsO with treated anxiety/depression cohort who had hospitalizations, 
ER visits, physician office visits, and other outpatient services (all p<.01). 

 — PsO related total healthcare costs were not significantly different between 
the PsO with treated anxiety/depression group and the PsO without treated 
anxiety/depression group.

Table 2. Annual All-cause and PsO-related Healthcare Costs of the Study Patients
Matched PsO  
with Treated  

Anxiety/Depression

Matched PsO  
without Treated  

Anxiety/Depression
Unadjusted  

mean difference p-value

Adjusted* 
mean 

difference p-value

All-cause costs 
(mean, SD)

Total costs $50,300 $44,271 $39,881 $28,490 $10,419 <.01 $6,343 <.01

Medical costs $18,696 $39,280 $9,531 $21,539 $9,165 <.01 $5,618 <.01

Pharmacy costs $31,604 $24,533 $30,350 $21,971 $1,254 0.19 $414 0.67

PsO-related costs 
(mean, SD)

        

Total costs $28,654 $24,632 $29,548 $21,373 -$894 0.48 -$1,393 0.28

Medical costs $2,626 $13,789 $1,747 $8,410 $879 <.01 $366 0.01

Pharmacy costs $26,028 $21,464 $27,801 $20,908 -$1,773 0.24 -$1,906 0.21
*The adjusted costs were estimated using GLM with gamma distribution after adjusting the following variables: QCI, Other Psychiatric 
Conditions, Psoriatic Arthritis, Rheumatoid Arthritis, Diabetes, Hypertension, Hyperlipidemia, Obesity, Thyroid Disease.

 ■ Compared with matched PsO controls, PsO patients with both treated anxiety 
and depression had $14,539 higher mean costs, PsO patients with treated 
depression only had $10,262 higher mean costs and PsO patients with treated 
anxiety only had $7,052 higher mean costs (all p<.01; Figure 3).

Indirect Healthcare Costs 
 ■ Among those patients who could be linked with absenteeism records (n=99), 

PsO patients with treated anxiety/depression had a mean of 22 (316 vs 294, 
p=.45) more work hours lost and $44 ($6,759 vs $6,714, p=.95) higher indirect 
costs due to absenteeism than matched PsO controls.

 ■ Among those patients who could be linked with the short term disability records 
(n=96), PsO patients with treated anxiety/depression had a mean of 23 (63 vs 
40, p=0.02) more lost days and $2,776 ($7,487 vs $4,711, p=0.01) higher 
indirect costs due to disability than matched PsO controls.

Figure 3. Healthcare Costs Stratified by Patients with Treated Anxiety Only, 
Depression Only, or both Anxiety and Depression

Pharmacy costs Medical costs

$13,547
$8,917

$32,154

$29,731

$20,208

$10,710

$31,360

$30,596

$22,312

$8,432

$31,344

$30,685

$0

$10,000

$20,000

$30,000

$40,000

$50,000

$60,000

Anxiety only
(n=713)

Controls
(n=713)

Depression
only

(n=949)

Controls
(n=949)

Anxiety and
Depression

(n=619)

Controls
(n=619)

§All p<0.01

Limitations
 ■ Administrative claims data were collected for facilitating payment for healthcare 

services; therefore, definitive diagnoses are not available, and the true prevalence 
of treated anxiety and/or depression may be underestimated. 

 ■ Indirect costs may be also underestimated as presenteeism was not available 
in the database; however, indirect costs due to absenteeism and short-term 
disability were reported.

 ■ The study was composed of patients covered by commercial insurance; 
therefore, the results may not be generalizable to PsO patients with other or no 
insurance coverage.

Conclusions
 ■ PsO patients with treated anxiety/depression in a commercially insured 

population incur a substantial incremental economic burden over matched PsO 
patients without treated anxiety/depression, primarily driven by greater use of  
medical services. 

 ■ While further research is needed to confirm these findings, PsO treatments 
that relieve psychiatric symptoms such as anxiety and depression may reduce 
incremental economic burden to benefit patients and the healthcare system.

References
1. Han C, Lofland JH, Zhao N, Schenkel B. Increased prevalence of psychiatric disorders and health care-associated costs among 

patients with moderate-to-severe psoriasis. J Drugs Dermatol. 2011 Aug;10(8):843-50.
2. Soliman AM, Surrey E, Bonafede M et al. Real-World Evaluation of Direct and Indirect Economic Burden Among ndometriosis 

Patients in the United States. Adv Ther. 2018;35(3):408-423.

This study was supported by Janssen Scientific Affairs, LLC

Economic Burden of Comorbid Anxiety and Depression among Patients with Moderate to Severe Psoriasis
Q. Cai, MS, MSPH,1 A. Teeple, MPH,1 B. Wu, MS,1 S. Shrivastava, BEng,2 E. Muser, PharmD, MPH1
1Janssen Scientific Affairs, Titusville, NJ; 2Mu-Sigma, Bengaluru, India