ORIGINAL
ARTICLES
Health care resource use, productivity, and costs among patients with moderate to severe plaque psoriasis in the United States Caroline P. Schaefer, MBA,a Joseph C. Cappelleri, PhD,c Rebecca Cheng, PharmD, MS,b Jason C. Cole, PhD,b Scott Guenthner, MD,d Joseph Fowler, MD,e Sandy Johnson, MD,f and Carla Mamolo, PhDc Gaithersburg, Maryland; San Diego, California; Groton, Connecticut; Plainfield, Indiana; Louisville, Kentucky; and Fort Smith, Arkansas Background: Comprehensive studies on costs of moderate to severe plaque psoriasis (MSPP) have not been conducted in the United States. Objective: We sought to evaluate current health care resource use, productivity, and costs among patients with MSPP in routine practice. Methods: A total of 200 adults seeking MSPP treatment enrolled in 9 US sites. Consented patients reported symptoms, treatment, lost productivity, and costs; 6-month retrospective chart review captured health care resource use and clinical characteristics. Costs were assigned to health care resource use and lost productivity using standard algorithms. Differences by Psoriasis Area and Severity Index (PASI) group, based on PASI score (#10, [10-#20, [20) at enrollment, were evaluated. Analyses included descriptive statistics and analysis of variance or Kruskal-Wallis tests. Results: Most patients (79.5%) were prescribed 1 or more MSPP medications (mean: 1.5); 36.0% and 9.0% received self-administered biologics and systemic therapies, respectively. Mean number of nonprescription treatments was 12.3. Differences by PASI group were observed for overall work and activity impairment (P \ .02). Six-month total MSPP direct costs per patient were $11,291; indirect costs were $2101 and differed across PASI groups (P = .0008). Limitations: This study enrolled patients with MSPP actively seeking care. Conclusion: Despite treatment, a number of patients with MSPP continue to experience moderate to severe PASI scores, impaired functioning, and high costs suggesting a need for new treatment options. ( J Am Acad Dermatol 2015;73:585-93.) Key words: burden of illness; chart review; costs; economic burden; health care resource use; moderate to severe plaque psoriasis; observational research; productivity.
pproximately 20% of patients with plaque psoriasis are thought to have moderate to severe plaque psoriasis (MSPP).1-3 Plaque psoriasis has been associated with depression,
A
immune-mediated inflammatory conditions, lymphoma, metabolic syndrome and obesity, and myocardial infarction2,4; severe psoriasis has even been associated with shortened survival.1,2 MSPP has
From Covance Market Access Services Inc, Gaithersburga and San Diegob; Pfizer Inc, Grotonc; Dermatology Center of Indianad; University of Louisvillee; and Johnson Dermatology, Fort Smith.f This research was supported by Pfizer. Disclosure: Dr Cheng and Ms Schaefer are employees of Covance Market Access Services Inc, which was paid by Pfizer to design and execute this study and to develop this manuscript. Dr Cole was an employee of Covance Market Access Services Inc at the time of the study; currently, Dr Cole is an employee of Pharmaceutical Product Development LLC. Dr Cappelleri and Dr Mamolo are employees of Pfizer. Dr Fowler, Dr Guenthner, and Dr Johnson were paid investigators for the study; they were not financially compensated for collaborative efforts on publication-related activities.
Accepted for publication June 24, 2015. Reprints not available from the authors. Correspondence to: Caroline P. Schaefer, MBA, Covance Market Access Services Inc, Gaithersburg MD. E-mail: caroline.
[email protected]. Published online August 4, 2015. 0190-9622 Ó 2015 by the American Academy of Dermatology, Inc. Published by Elsevier, Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-ncnd/4.0/). http://dx.doi.org/10.1016/j.jaad.2015.06.049
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been shown to negatively impact health-related had been conducted in the United States to our quality of life5; patients with psoriasis report similar knowledge. Because extrapolating non-US findings or worse health-related quality of life compared with to the United States is not straightforward as a result chronic diseases such as diabetes.6 of differences in health care delivery systems and Guidelines discuss patients with MSPP receiving costs across countries, a gap remains in the underconventional systemic therapies, biologic agents, standing of MSPP costs in the United States. Recently phototherapy, and topical agents alone or in combithe United States Centers for Disease Control and nation.2,7,8 Previous studies, Prevention (CDC) published such as the National Psoriasis recommendations for addiCAPSULE SUMMARY Foundation survey (2003tional public health research 2005), have found a substaninto the HCRU, impact on The economic burden of moderate to tial proportion of patients ability to work, and costs severe plaque psoriasis has been studied do not seek treatment or are associated with psoriasis.31,32 9 in Europe and Canada. undertreated. This study aimed to evaluate MSPP costs include direct This study captures medication use, the economic burden of costs to payers, (eg, derhealth care resource use, lost MSPP in the United States matologist office visits, productivity, direct and indirect costs by capturing its impact prescription or physicianassociated with moderate to severe on HCRU, productivity, and administered treatments, hosplaque psoriasis in the United States by direct and indirect costs pitalization), out-of-pocket Psoriasis Area and Severity Index score. among patients actively costs to patients, and indirect seeking treatment via patient Results can help US clinicians understand costs (eg, lost productivity as survey and medical chart impacts of real-world treatment patterns a result of absenteeism).9-15 review. and remaining unmet need. Most economic studies to date have included all patients with psoriasis.15 An analysis of 2003 data METHODS reported significantly greater annual costs for MSPP Study design and data sources compared with mild psoriasis ($10,593 vs $5011) and This US observational study included a crossidentified the primary cost driver of MSPP to be sectional survey and 6-month retrospective chart reoutpatient visits.10 More recent observational studies view. Patients with plaque psoriasis and body surface have identified pharmacotherapy and other treatarea (BSA) of 10 or higher at enrollment or in the prior ments as primary cost drivers.14,16,17 One study 6 months, or on systemic therapy or phototherapy (or reported the average annual cost of MSPP to be both) for MSPP at screening were eligible.* Eligible $11,029 and $26,708 for patients treated with conpatients were 18 years or older, willing and able to ventional systemics and biologics, respectively.17 Use provide written informed consent, able to read and of alternative, nonmedical therapies and correspondunderstand English, treated at the physician’s practice ing high out-of-pocket costs among patients with for at least 6 months, and given a diagnosis of MSPP MSPP have also been observed.12,18 more than 6 months before enrollment. Patients were Psoriasis has been associated with negative imineligible if they had participated in an investigational pacts on productivity and finances.6,11-16,19-23 In 1 drug study in the 6 months before enrollment; had a United Kingdom study, patients missed an average of serious or unstable medical or psychological condition 26 work days annually as a result of MSPP.19 An Italian that, in the opinion of the physician, would comprostudy reported that absenteeism (or loss of leisure mise participation in the study; or had psoriasis other time for nonemployed patients) accounted for 32% of than plaque psoriasis. total MSPP-related costs.11 A recent US survey found Patients with MSPP were recruited (January that compared with patients with mild psoriasis, through May 2012) during a routine physician office patients with severe disease were less likely to work visit at 1 of 9 participating sites: 8 community-based full-time and significantly more likely to report that dermatologists and 1 primary care physician. The 9 psoriasis was the reason for not working.20 sites were located in 8 US states: Nebraska, Illinois, Although studies have been conducted in North Carolina, Indiana, Arkansas, California, Europe11-13,16,24-27 and Canada14,28-30 to assess Kentucky, and Florida. There was competitive health care resource use (HCRU), productivity, and enrollment among sites until the overall target costs associated with psoriasis, at the time of this study no comprehensive studies of the economic *PASI and BSA were calculated at the site. Sites received studyburden of MSPP, including direct and indirect costs, specific training on calculating the scores for PASI and BSA. d
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Abbreviations used: BSA: CDC: HCRU: MSPP: PASI:
body surface area Centers for Disease Control and Prevention health care resource use moderate to severe plaque psoriasis Psoriasis Area and Severity Index
sample size (200 patients) was achieved; no single site was allowed to enroll more than 40 patients. Patients completed a cross-sectional survey that included questions about sociodemographics, psoriasis clinical characteristics and symptoms, current employment status, changes in employment status as a result of MSPP, out-of-pocket costs related to psoriasis over the past 4 weeks, and several validated patient-reported outcome instruments, including the Work Productivity and Activity Impairment: Psoriasis, a 6-item instrument assessing overall work impairment, ie, absenteeism, presenteeism, and activity impairment33 attributable to MSPP. Study site personnel completed a case report form based on a 6month retrospective chart review that captured Psoriasis Area and Severity Index (PASI) score; percent BSA; clinical history and characteristics; and MSPP-related HCRU over the past 6 months, including hospitalizations, office-based and hospital outpatient visits and treatments (eg, phototherapy), tests, procedures, and infusions performed, use of a phototherapy home device, and prescribed medications. Patients provided written informed consent,34 and study materials were approved by Schulman Associates Institutional Review Board Inc (Cincinnati, OH). Calculation of MSPP costs Costing algorithms were used to assign 2012 unit costs (US$) from published sources to HCRU data captured in the retrospective chart review and patient-reported lost productivity data35 to calculate 6-month costs. Sources for unit costs and details of the costing approach are presented in the ‘‘Costs of MSPP’’ section of this article. Analysis methods Summary statistics were used to describe the sample.36,37 Although all enrolled patients had moderate to severe disease, PASI score at enrollment was used to determine analysis groups, based on European Medicines Agency psoriasis guidance: less than or equal to 10 (mild), greater than 10 to 20 (moderate), and greater than 20 (severe).7
For continuous variables, differences by PASI group were compared using 1-way analysis of variance or the Kruskal-Wallis test if normality of the data distribution was not confirmed. In cases where Kruskal-Wallis was used, whereas the means and SDs are presented, the P value presented is based on the ranks and hence involves a difference in population medians between independent groups. The 95% confidence interval of the difference between group means also was reported by PASI group. For categorical variables, differences by PASI group were compared using the x 2 or Fisher exact test. Statistical significance was evaluated at the 2tailed .05 level of significance. Statistical analyses were performed using software (SAS, Version 9.1.3, SAS Institute Inc, Cary, NC).
RESULTS Demographic and clinical characteristics Male and female patients were equally represented (N = 200) (Table I, available at http://www. jaad.org). The mean age was 51.4 years; 62% were employed. Mean PASI score at enrollment was 8.6; 71.5% were in the mild PASI group, 18.0% in the moderate PASI group, and 10.5% had severe PASI. Most patients (88.0%) were Caucasian. Statistically significant differences across PASI groups were observed for race and weight (P = .0097 and P \.0001, respectively). Mean time since diagnosis was 15.6 years (median: 11.4 years). Mean BSA at enrollment was 10.8% overall; patients with moderate and severe PASI had higher mean BSA scores (24.1% and 25.6%, respectively) than those with mild PASI (5.2%, P \.0001) (Table I). Based on retrospective chart review, those with moderate PASI had worsening BSA scores over the previous 6 months, with the lowest mean scores at enrollment, whereas the severe PASI group’s BSA had remained relatively stable and high in the same time frame. Of patients, 72% reported psoriasis affected 3 or more body parts (Fig 1). Comorbidities were prevalent (mean: 2.0) (Table I). In all, 59 (29.5%) subjects had psoriatic arthritis in addition to their MSPP. Treatment patterns and HCRU Most patients (79.5%) were prescribed 1 or more MSPP medications (Table II, available at http://www. jaad.org); 20.5% were not receiving any MSPP prescription medication. Mean number of prescription medications per patient was 1.5, with a significant difference across PASI groups (P = .0162). Fig 2 presents the proportions of patients who received biologics, systemics, phototherapy (at home or in
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Fig 1. Body parts affected by moderate to severe plaque psoriasis, as reported by patients. Data for 4 patients were missing.
Fig 2. Moderate to severe plaque psoriasis medication use in the past 6 months. *Composed of physician- and self-administered biologics including alefacept, infliximab, ustekinumab, etanercept, and adalimumab. yComposed of physician- and self-administered conventional systemic therapies including triamcinolone acetonide, cyclosporine, doxepin hydrochloride, folic acid, hydrochlorothiazide and triamterene, hydroxyzine hydrochloride, methotrexate, penicillin potassium, prednisone, and acitretin. Using the Fisher exact test, a significant difference was observed across Psoriasis Area and Severity Index (PASI ) groups for topicals (P = .0201) and biologics (P = .0130). For categorical variables, differences by PASI group were compared using Fisher exact test if expected counts were less than 5 patients per cell.
the physician office), and topicals. The differences in use of topicals and biologics among the 3 PASI groups were significant (P = .0201 and P = .0130, respectively); the severe PASI group had the highest proportion of patients reporting use of topicals. A higher percentage (33.3%) of patients in the severe PASI group were prescribed topicals only compared with 15.4% and 19.4% in the mild and moderate PASI groups, respectively. Approximately one third of patients used 5 or more nonprescription psoriasis treatments in the 4 weeks before enrollment.
There was a mean of 3.4 MSPP office visits, 1.4 office-based tests and procedures, and 0.7 officebased phototherapy sessions per patient in the past 6 months. Across the PASI groups, similar levels of HCRU were observed. Productivity and changes in employment status Among those employed, overall work impairment as a result of MSPP was approximately 14% (Fig 3). This was predominantly related to impairment at
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Fig 3. Moderate to severe plaque psoriasis (MSPP). Mean Work Productivity and Activity Impairment: Psoriasis (WPAI:PsO) scores. Raw scores are multiplied by 100 and expressed as impairment percentages, with higher values indicating greater impairment.42 *Among those employed for pay. WPAI:PsO scores are expressed as impairment percentages: absenteeism is percent work time missed as a result of MSPP; presenteeism is percent impairment while working as a result of MSPP; overall work impairment is percent overall impairment as a result of MSPP, composed of absenteeism and presenteeism; and activity impairment is percent activity impairment. Using the Kruskal-Wallis test, a significant difference in medians was observed across Psoriasis Area and Severity Index (PASI ) groups for absenteeism (PASI $10: 0.0, 10\PASI #20: 0.0, PASI[20: 0.0; P = .0460), presenteeism (PASI $10: 0.0, 10\PASI #20: 10.0, PASI[20: 10.0; P = .0262), overall work impairment (PASI $10: 0.0, 10\PASI #20: 10.0, PASI[20: 12.6; P = .0103), and activity impairment (PASI $10: 0.0, 10\PASI #20: 20.0, PASI[20: 20.0; P \.0001). For continuous variables, differences by PASI group were compared using Kruskal-Wallis if data were not normally distributed. Normality was assessed using skewness and Kurtosis z-scores, wherein a z-score of \5.0 was considered as providing sufficient evidence for normality to use the parametric test.43 Researchers have found analysis of variance, which tests for differences in means, to be robust upward of a skewness z of 10 or 1244; however, we opted for a more conservative value of 5.0.
work (presenteeism), rather than missed work (absenteeism). Overall work impairment was highest for the severe PASI group (25.0%). Mean activity impairment was similarly high among moderate and severe PASI groups (27.2% and 27.1%, respectively). Differences across PASI groups were significant for both Work Productivity and Activity Impairment: Psoriasis scores (P = .0103 and P \.0001) (Fig 3). MSPP had no impact on employment status for the majority of patients (n = 184) (Table III, available at http://www.jaad.org). Significant differences were observed across PASI groups for change in roles as a result of MSPP (P \.03). In addition, there were significant differences across PASI groups for the mean time spent applying topicals (P = .0003) and vacuuming (P = .0145).
Costs of MSPP Average 6-month total direct costs per patient are presented in Fig 4; the largest components were for prescription treatments and office-based infusions across the PASI groups. (All patients in the sample had MSPP; the sample was then categorized by baseline PASI score into three group: mild PASI, moderate PASI, and severe PASI.) No significant differences across PASI groups were observed for total direct costs. Average 6-month total indirect costs per patient increased from mild to moderate to severe PASI groups (P = .0008) (Fig 5). Across the 3 PASI groups, average 6-month indirect costs associated with lost work productivity accounted for more than 75% of the total indirect cost per patient.
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Fig 4. Moderate to severe plaque psoriasis (MSPP). Mean 6-month direct costs (2012 US$). *Includes out-of-pocket costs to patients for direct medical and nonmedical expenses. Patientreported out-of-pocket costs did not need to be monetized; 4-week costs were extrapolated to 26 weeks (multiplied by 6.5). The average 6-month out-of-pocket costs to patients for direct medical expenses were higher than those for nonmedical expenses for all Psoriasis Area and Severity Index (PASI ) groups; a significant difference across PASI groups was observed for the nonmedical expenses: $309 for the moderate PASI group compared with $69 and $68 for the mild and severe PASI groups, respectively (P = .0007). yIncludes direct costs to payers for MSPP-related office-based visits, office-based tests and procedures (excluding infusions), hospitalizations, and prescribed phototherapy home devices. Unit costs were assigned using the fiscal year 2012 Medicare physician fee schedule, Hospital Outpatient Prospective Payment System, and Hospital Inpatient Prospective Payment System; for each hospitalization reported, the discharge diagnosis, procedures performed, and length of stay were used to identify appropriate diagnosis-related groups to estimate costs. zUnit costs for MSPP-related officebased infusions were assigned using the average sales price and fiscal year 2012 Medicare physician fee schedule. xUnit costs for MSPP-related prescription treatments were assigned using 2012 average wholesale price, adjusted for discounts and dispensing fees. Using the Kruskal-Wallis test, no significant differences in medians were observed across PASI groups for total 6-month direct costs per patient (means: $11,662 vs $10,460 vs $10,187; medians: $12,104 vs $4851 vs $5082; P = .4084). For continuous variables, differences by PASI group were compared using Kruskal-Wallis if data were not normally distributed. Normality was assessed using skewness and Kurtosis z-scores, wherein a z-score of \5.0 was considered as providing sufficient evidence for normality to use the parametric test.43 Researchers have found analysis of variance, which tests for differences in means, to be robust upward of a skewness z of 10 or 1244; however, we opted for a more conservative value of 5.0.
DISCUSSION This study describes current treatment patterns, HCRU, lost productivity, and associated 6-month direct and indirect costs among patients with MSPP in US routine clinical practice. A strength of the study is that it combines patient survey and chart review to comprehensively capture economic burden, including patient-reported nonprescription treatments, out-of-pocket costs, work impairment, and changes in employment status, which are not captured using medical claims data. Our sample was similar to others based on a broad set of clinical and demographic variables,6,23 and there were few significant differences across PASI groups. We observed that patients with severe PASI tended to weigh more, and note that the association
between MSPP and weight or other comorbidities associated with increased weight is an area for future research suggested by the CDC.31,32 In our study, 49% of patients reported that 5 or more body parts were affected by psoriasis, consistent with European findings.23 Mean BSA scores at enrollment and over the past 6 months in the moderate and severe PASI groups suggest patients with moderate PASI were worsening as a result of fluctuation in disease, changes in treatment, or both. To better understand those with PASI scores greater than 10 to 20, additional research is warranted. A majority of patients had mild PASI scores at enrollment, suggesting patients were relatively well treated, although they met the MSPP criteria. Many patients were taking a biologic, and few patients
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Fig 5. Moderate to severe plaque psoriasis (MSPP). Mean 6-month indirect costs (2012 US$). *Based on patient-reported lost productivity because of changes in employment status as a result of MSPP, including unemployment, early retirement, disability, or reduced work schedule. Costs of employment status changes were calculated by multiplying mean hourly wage in the United States45 and mean monthly disability payment46 by lost productive time since change in employment status as a result of MSPP (up to 26 weeks). Using the KruskalWallis test, a significant difference in medians was observed across Psoriasis Area and Severity Index (PASI ) groups for 6-month total indirect costs per patient (means: $1617 vs $2625 vs $4503; medians: $0 vs $0 vs $2288; P = .0008). For continuous variables, differences by PASI group were compared using Kruskal-Wallis if data were not normally distributed. Normality was assessed using skewness and Kurtosis z-scores, wherein a z-score of \5.0 was considered as providing sufficient evidence for normality to use the parametric test.43 Researchers have found analysis of variance, which tests for differences in means, to be robust upward of a skewness z of 10 or 1244; however, the authors opted for a more conservative value of 5.0. y Based on patient-reported lost productivity as a result of absenteeism and presenteeism measured by the Work Productivity and Activity Impairment: Psoriasis. Work-related impairment costs were calculated by multiplying lost productive time by the mean hourly wage in the United States45 according to method proposed by Lofland et al35; 1eweek costs were extrapolated to 26 weeks.
were taking a conventional systemic treatment or using phototherapy at home to manage their MSPP. The most commonly reported treatment type across all 3 PASI groups was topical therapy; although a minority of patients in each group was treated with topicals alone, the highest proportion was in the severe PASI group. Although 20.5% of our sample was not receiving any prescription medications for their MSPP, this proportion was lower than previous estimates of 37% to 39%.9 Earlier studies were conducted around the time of Food and Drug Administration approval of biologics for MSPP; thus, differences in treatment patterns may be a result of the availability of newer therapies. In addition, patients in this study were actively seeking care and thus, may have been more likely to receive a prescription for their MSPP and also may have been more motivated and/or diligent about managing their disease than patients not included. Overall work impairment as a result of MSPP among those employed was consistent with another US survey (15.5%),38 and largely driven by presenteeism. Although presenteeism was high for both the moderate and severe PASI groups, those with severe
PASI reported higher levels of absenteeism and changes in employment status as a result of MSPP, which explains their higher total indirect costs compared with the other PASI groups. MSPP is a common condition that imparts profound economic impact on payers, employers, and patients. There are limited published US studies that assess the economic burden of MSPP10,17,20,39,40 and none to our knowledge that provide a comprehensive assessment of the economic burden.31,32 Patients with MSPP in our study had high direct costs across PASI groups, driven by prescription treatments and office-based infusions. Total direct costs were comparable with previous estimates among patients with MSPP treated with biologics15,17,40 and exceeded published annual direct costs of rheumatoid arthritis.41 Use of high-cost treatments among mild and moderate PASI groups was prevalent, suggesting consistent treatment patterns among patients with MSPP, with a proportion who are well controlled. Compared with previous French results, out-of-pocket medical care costs to patients were higher and the proportion as a result of nonprescription treatments was lower in our sample.12 Indirect
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costs were prevalent and increased significantly as PASI severity worsened. Total costs, cost drivers, and proportion of costs driven by indirect costs observed in this US study were comparable with several recent non-US studies11,14,16; although, differences in health care systems limits the degree to which such comparisons can be made. The results suggest that costs and expenses related to HCRU and lost productivity incurred by the proportion of patients whose MSPP is not well controlled are markedly higher than those patients who experience better treatment outcomes. Limitations Several potential limitations should be considered when interpreting study findings. The study focused on patients with MSPP actively seeking care. Thus, our sample may not be representative of patients with MSPP in the general population who are untreated or not regularly seeking care. Retrospective review of medical records may have led to underreporting of HCRU, as enrolling sites may not have recorded care provided elsewhere for their patients’ psoriasis. Although sites were instructed to discuss MSPP-related care provided outside the study site with patients, it is possible some MSPP HCRU was not captured. Direct costs were assigned using a standard algorithm; actual costs to the payer may be higher or lower. The Medicare fee schedule tends to underestimate costs, as private insurers may reimburse at higher rates. Out-of-pocket costs and lost productivity data were based on patient recall and extrapolated to 6 months; this may have resulted in overestimation or underestimation of costs. Conclusions To our knowledge, this is one of the first studies to comprehensively evaluate the economic burden of MSPP in the United States, including direct costs to payers, out-of-pocket costs to subjects, and indirect costs as a result of lost productivity. Despite substantial HCRU, a proportion of patients continue to experience work and activity impairment, moderate to severe PASI scores, and high costs. For patients whose MSPP is not well controlled, different treatment options should be explored until better outcomes and patient satisfaction are achieved. The authors would like to acknowledge the following employees of Covance Market Access Services Inc: Felicia Bergstrom, MSPH, who contributed to study design and analysis; Rebecca Baik, BA, Eun young Kim, MS, and Shoshana Daniel, PhD, who provided programming support for the analysis; and Rachael Mann, BA, who provided medical writing support for the manuscript (funded by Pfizer Inc).
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20. Horn EJ, Fox KM, Patel V, Chiou CF, Dann F, Lebwohl M. Association of patient-reported psoriasis severity with income and employment. J Am Acad Dermatol. 2007;57(6):963-971. 21. de Korte J, Sprangers MA, Mombers FM, Bos JD. Quality of life in patients with psoriasis: a systematic literature review. J Investig Dermatol Symp Proc. 2004;9:140-147. 22. Gowda S, Goldblum OM, McCall WV, Feldman SR. Factors affecting sleep quality in patients with psoriasis. J Am Acad Dermatol. 2010;63(1):114-123. 23. Dubertret L, Mrowietz U, Ranki A, et al. European patient perspectives on the impact of psoriasis: the EUROPSO patient membership survey. Br J Dermatol. 2006;155:729-736. 24. Raho G, Koleva DM, Garattini L, Naldi L. The burden of moderate to severe psoriasis: an overview. Pharmacoeconomics. 2012;30(11):1005-1013. 25. Spandonaro F, Altomare G, Berardesca E, et al. Health-related quality of life in psoriasis: an analysis of Psocare project patients. G Ital Dermatol Venereol. 2011;146(3):169-177. 26. Parrish L. Psoriasis: symptoms, treatments and its impact on quality of life. Br J Community Nurs. 2012;17(11):524, 526, 528. 27. Wheeler T. Psoriasis: the burden of disease and treatment. Br J Nurs. 2010;19(15):946. 28. Wasel N, Poulin Y, Andrew R, Chan D, Fraquelli E, Papp K. A Canadian self-administered online survey to evaluate the impact of moderate-to-severe psoriasis among patients. J Cutan Med Surg. 2009;13(6):294-302. 29. Lynde CW, Poulin Y, Guenther L, Jackson C. The burden of psoriasis in Canada: insights from the pSoriasis Knowledge IN Canada (SKIN) survey. J Cutan Med Surg. 2009;13(5): 235-252. 30. Chan B, Hales B, Shear N, et al. Work-related lost productivity and its economic impact on Canadian patients with moderate to severe psoriasis. J Cutan Med Surg. 2009;13(4):192-197. 31. Helmick CG, Sacks JJ, Gelfand JM, et al. Psoriasis and psoriatic arthritis: a public health agenda. Am J Prev Med. 2013;44: 424-426. 32. Ryan C, Korman NJ, Gelfand JM, et al. Research gaps in psoriasis: opportunities for future studies. J Am Acad Dermatol. 2014;70(1):146-167. 33. Reilly MC, Zbrozek AS, Dukes EM. The validity and reproducibility of a work productivity and activity impairment instrument. Pharmacoeconomics. 1993;4(5):353-365. 34. General Assembly. Declaration of Helsinki. Adopted by the 18th World Medical Assembly (WMA) General Assembly Helinski, Finland, 1964; amended by the 29th WMA General Assembly in Tokyo, Japan in 1975, the 35th WMA General Assembly in
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Table I. Demographic and clinical characteristics of the participating patients Characteristic
Age, mean (SD), y* Male, n (%)y Race, n (%)y Caucasian Other Height, mean (SD), in* Weight, lb Mean (SD)z Median Employment status, n (%)y Missing Employed for pay Not employed for pay Missing Disabled Retired Unemployed Full-time homemaker Other Health insurance coverage, n (%) Missing No Yes Prescription coverage, n (%) Comorbidity reported, n (%)x Comorbidities, mean (SD)*{ BSA on date of assessment Mean (SD)zk Median PASI on date of assessment Mean (SD)zk Median Time since diagnosis, y Mean (SD)z Median Patient-reported psoriasis severity, n (%)y Missing Severe Moderate Mild Almost clear Clear (no psoriasis)
Overall (n = 200)
PASI #10 (n = 143, 71.5%)
10\PASI #20 (n = 36, 18.0%)
PASI[20 (n = 21, 10.5%)
51.4 (14.08) 100 (50.0)
52.0 (14.45) 66 (46.2)
53.1 (12.62) 24 (66.7)
44.8 (12.50) 10 (47.6)
176 (88.0) 24 (12.0) 67.2 (3.72)
131 (91.6) 12 (8.4) 66.9 (3.66)
26 (72.2) 10 (27.8) 67.9 (3.68)
19 (90.5) 2 (9.5) 68.6 (3.81)
201.0 (53.11) 193.0
190.4 (43.88) 185.0
214.5 (56.66) 202.0
250.0 (71.58) 254.0
P value
.0653 .0859 .0087
.0601 \.0001 .2996
1 123 76 3 16 32 12 8 5
(0.5) (61.5) (38.0) (3.9) (21.1) (42.1) (15.8) (10.5) (6.6)
1 87 55 1 12 24 8 7 3
(0.7) (60.8) (38.5) (1.8) (21.8) (43.6) (14.5) (12.7) (5.5)
0 20 16 1 3 6 4 1 1
(0.0) (55.6) (44.4) (6.3) (18.8) (37.5) (25.0) (6.3) (6.3)
0 16 5 1 1 2 0 0 1
(0.0) (76.2) (23.8) (20.0) (20.0) (40.0) (0.0) (0.0) (20.0)
14 26 160 159 150 2.0
(7.0) (13.0) (80.0) (79.5) (75.0) (1.14)
8 13 122 120 107 2.0
(5.6) (9.1) (85.3) (83.9) (74.8) (1.10)
3 9 24 25 26 2.3
(8.3) (25.0) (66.6) (69.4) (72.2) (1.34)
3 4 14 14 17 2.1
(14.3) (19.0) (66.6) (66.7) (81.0) (1.05)
N/A
.0254 N/A .4729
10.8 (13.98) 6.0
5.2 (6.17) 3.0
24.1 (17.67) 20.0
25.6 (18.85) 20.0
\.0001
8.6 (11.12) 4.3
3.3 (2.52) 2.80
13.9 (2.29) 13.65
36.0 (11.60) 34.00
N/A
15.6 (14.57) 11.4
15.8 (14.60) 11.2
17.8 (15.08) 18.2
10.4 (12.74) 3.25
.0828 \.0001
1 31 56 41 60 11
(0.5) (15.5) (28.0) (20.5) (30.0) (5.5)
1 9 30 35 57 11
(0.7) (6.3) (21.0) (24.5) (39.9) (7.7)
0 14 14 6 2 0
(0.0) (38.9) (38.9) (16.7) (5.6) (0.0)
0 8 12 0 1 0
(0.0) (38.1) (57.1) (0.0) (4.8) (0.0)
BSA, Body surface area; N/A, not applicable; PASI, Psoriasis Area and Severity Index. *P values are from analysis of variance (ANOVA); PASI #10 vs 10\PASI #20 vs PASI[20. For continuous variables, differences by PASI group were compared using ANOVA if normality was confirmed. Normality was assessed using skewness and Kurtosis z-scores, wherein a z-score of \5.0 was considered as providing sufficient evidence for normality to use the parametric test.43 Researchers have found ANOVA to be robust upward of a skewness z of 10 or 1244; however, we opted for a more conservative value of 5.0. y P values are from Fisher exact test; PASI #10 vs 10\PASI #20 vs PASI[20. For categorical variables, differences by PASI group were compared using Fisher exact test if expected counts were \5 patients per cell. z P values are from Kruskal-Wallis test; PASI #10 vs 10\PASI #20 vs PASI[20. For continuous variables, differences by PASI group were compared using Kruskal-Wallis if data were not normally distributed. Normality was assessed using skewness and Kurtosis z-scores, wherein a z-score of \5.0 was considered as providing sufficient evidence for normality to use the parametric test.43 Researchers have found ANOVA to be robust upward of a skewness z of 10 or 1244; however, we opted for a more conservative value of 5.0. x P values are from x2; PASI #10 vs 10\PASI #20 vs PASI[20. For categorical variables, differences by PASI group were compared using the x 2 test if expected counts were $5 patients per cell. { Among patients with at least 1 comorbid condition. k Higher values indicate worse outcomes.
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Table II. Medication and health care resource use for moderate to severe plaque psoriasis patients in the past 6 months Characteristic
No. of prescribed MSPP medications per patient Mean (SD)* Median No. of prescribed MSPP medications, n (%)y 0 1 2 3 4 5 $6 No. of different physician-administered medications per patient Mean (SD)* Median No. of physician-administered medications, n (%)z 0 1 $2 No. of nonprescription treatments used Mean (SD)*x Median No. of nonprescription treatments, n (%)yx 0 1 2 3 4 $5 No. of physician office visits Mean (SD)* Median No. of tests or procedures Mean (SD)* Median Patients receiving test or procedure at least oncez Excimer laser No Yes No. of hospital outpatient or emergency department visits Mean (SD)* Median Hospitalization, n (%)z No. of hospitalizations Mean (SD)*{ Median
Overall (n = 200)
PASI #10 10\PASI #20 PASI[20 (n = 143, 71.5%) (n = 36, 18.0%) (n = 21, 10.5%) P value
1.5 (1.32) 1.0
1.5 (1.34) 1.0
1.3 (1.28) 1.0
2.1 (1.18) 2.0
41 78 48 17 6 8 2
30 59 32 10 4 7 1
10 14 6 5 0 0 1
1 5 10 2 2 1 0
.0162 .0573
(20.5) (39.0) (24.0) (8.5) (3.0) (4.0) (1.0)
(21.0) (41.3) (22.4) (7.0) (2.8) (4.9) (0.7)
(27.8) (38.9) (16.7) (13.9) (0.0) (0.0) (2.8)
(4.8) (23.8) (47.6) (9.5) (9.5) (4.8) (0.0)
0.3 (0.47) 0.0
0.3 (0.46) 0.0
0.3 (0.53) 0.0
0.1 (0.36) 0.0
143 (71.5) 56 (28.0) 1 (0.5)
100 (69.9) 43 (30.1) 0 (0.0)
25 (69.4) 10 (27.8) 1 (2.8)
18 (85.7) 3 (14.3) 0 (0.0)
12.3 (25.04) 0.0
11.5 (24.52) 0.0
16.8 (30.66) 0.0
10.3 (16.64) 0.0
.3078 .1814
.4239 .2357
127 1 4 2 1 65
(63.5) (0.5) (2.0) (1.0) (0.5) (32.5)
95 1 1 1 0 45
(66.4) (0.7) (0.7) (0.7) (0.0) (31.5)
20 0 2 0 0 14
(55.6) (0.0) (5.6) (0.0) (0.0) (38.9)
12 0 1 1 1 6
(57.1) (0.0) (4.8) (4.8) (4.8) (28.6)
3.4 (5.26) 2.0
3.2 (5.26) 1.0
4.1 (6.38) 2.0
2.8 (2.55) 2.0
.3860
1.4 (4.87) 0.0
1.4 (4.81) 0.0
1.9 (6.02) 0.0
0.6 (2.62) 0.0
.4014
186 (93.0) 14 (7.0)
132 (92.3) 11 (7.7)
34 (94.4) 2 (5.6)
20 (95.2) 1 (4.8)
0.0 (0.00) 0.0 1 (0.5)
0.0 (0.00) 0.0 0 (0.0)
0.0 (0.00) 0.0 1 (2.8)
0.0 (0.00) 0.0 0 (0.0)
1.0000
1.0 (.) 1.0
1.0 (.) 1.0
N/A .2850 N/A
MSPP, Moderate to severe plaque psoriasis; N/A, not applicable; PASI, Psoriasis Area and Severity Index. *P values are from Kruskal-Wallis test; PASI #10 vs 10\PASI #20 vs PASI[20. For continuous variables, differences by PASI group were compared using Kruskal-Wallis if data were not normally distributed. Normality was assessed using skewness and Kurtosis z-scores, wherein a z-score of \5.0 was considered as providing sufficient evidence for normality to use the parametric test.43 Researchers have found analysis of variance to be robust upward of a skewness z of 10 or 1244; however, we opted for a more conservative value of 5.0. y P values are from x2; PASI #10 vs 10\PASI #20 vs PASI[20. For categorical variables, differences by PASI group were compared using the x 2 test if expected counts were $5 patients per cell. z P values are from Fisher exact test; PASI #10 vs 10\PASI #20 vs PASI[20. For categorical variables, differences by PASI group were compared using Fisher exact test if expected counts were \5 patients per cell. x In the past 4 wk. { Among those with a hospital stay.
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Table III. Changes in employment status, roles, and activities to manage moderate to severe plaque psoriasis among the sample Characteristic
Overall (n = 200)
PASI #10 (n = 143, 71.5%)
Impact of psoriasis on employment status, n (%)* Retired early 1 (0.5) 1 (0.7) Unemployed 2 (1.0) 1 (0.7) Disabled 0 (0.0) 0 (0.0) Reduced work schedule 0 (0.0) 0 (0.0) None 184 (92.0) 134 (93.7) Missing 13 (6.5) 7 (4.9) Patient-reported changes in activities and roles as a result of MSPP, n (%)* Not doing same activities at work as before psoriasis Somewhat/strongly agree 27 (13.5) 21 (14.7) Neither agree or disagree 16 (8.0) 10 (7.0) Somewhat/strongly disagree 128 (64.0) 91 (63.6) Missing 29 (14.5) 21 (14.7) Had to change job, role, or position at work because of psoriasis Somewhat/strongly agree 10 (5.0) 8 (5.6) Neither agree or disagree 9 (4.5) 5 (3.5) Somewhat/strongly disagree 152 (76.0) 108 (75.5) Missing 29 (14.5) 22 (15.4) Outside of work, not doing the same activities as a result of psoriasis Somewhat/strongly agree 48 (24.0) 27 (18.9) Neither agree or disagree 15 (7.5) 8 (5.6) Somewhat/strongly disagree 116 (58.0) 93 (65.0) Missing 21 (10.5) 15 (10.5) Time spent on activities related to MSPP during past 4 wk, miny Vacuuming Mean (SD)z 95.6 (218.65) 46.7 (43.69) Median 40.0 30.0 Washing sheets/clothes Mean (SD)z 149.5 (256.37) 124.5 (271.85) Median 60.0 60.0 Putting on topical Mean (SD)z 153.9 (318.80) 73.0 (107.82) Median 60.0 30.0 Going to the doctor Mean (SD)z 109.5 (94.03) 105.6 (102.85) Median 60.0 60.0 Getting laboratory work/medical care, mean (SD)x 55.0 (55.82) 54.0 (61.98) Getting phototherapy treatment, mean (SD)x 178.3 (208.65) 213.9 (248.52) Other activities, mean (SD)x 31.3 (20.97) 31.3 (20.97)
10\PASI #20 (n = 36, 18.0%)
PASI[20 (n = 21, 10.5%)
P value
.4350 0 0 0 0 32 4
(0.0) (0.0) (0.0) (0.0) (88.9) (11.1)
0 1 0 0 18 2
(0.0) (4.8) (0.0) (0.0) (85.7) (9.5) \.0001
2 2 25 7
(5.6) (5.6) (69.5) (19.4)
4 4 12 1
(19.1) (19.1) (57.1) (4.8) .0265
1 2 26 7
(2.8) (5.6) (72.1) (19.4)
1 2 18 0
(4.8) (9.5) (85.7) (0.0) .0002
13 3 14 6
(36.2) (8.3) (38.9) (16.7)
8 4 9 0
(38.1) (19.0) (42.9) (0.0)
199.8 (406.33) 121.7 (151.83) 60.0 60.0
.0145
188.4 (263.95) 184.2 (185.58) 90.0 90.0
.0943
305.5 (592.43) 277.1 (276.85) 60.0 120.0
.0003
115.8 (64.73) 124.0 (74.12) 120.0 120.0 59.3 (57.48) 53.3 (36.70) 146.8 (134.50) 15.0 (.)
.2455 .9754 .6445 N/A
P values for the categorical variables are calculated for the nonmissing categories. MSPP, Moderate to severe plaque psoriasis; N/A, not applicable; PASI, Psoriasis Area and Severity Index. *P values are from Fisher exact test; PASI #10 vs 10\PASI #20 vs PASI[20. For categorical variables, differences by PASI group were compared using Fisher exact test if expected counts were \5 patients per cell. y Among those spending any time on the specified activity. z P values are from Kruskal-Wallis test; PASI #10 vs 10\PASI #20 vs PASI[20. For continuous variables, differences by PASI group were compared using Kruskal-Wallis if data were not normally distributed. Normality was assessed using skewness and Kurtosis z-scores, wherein a z-score of \5.0 was considered as providing sufficient evidence for normality to use the parametric test.43 Researchers have found analysis of variance (ANOVA) to be robust upward of a skewness z of 10 or 1244; however, we opted for a more conservative value of 5.0. x P values are from ANOVA; PASI #10 vs 10\PASI #20 vs PASI[20. For continuous variables, differences by PASI group were compared using ANOVA if normality was confirmed. Normality was assessed using skewness and Kurtosis z-scores, wherein a z-score of \5.0 was considered as providing sufficient evidence for normality to use the parametric test.43 Researchers have found ANOVA to be robust upward of a skewness z of 10 or 1244; however, we opted for a more conservative value of 5.0.
