Psoriasis Involving Special Areas is Associated with Worse Quality of Life,Depression,and Limitations in the Ability to Participate in Social Roles and Activities

Abstract

Background

Psoriasis severity has traditionally been categorized as mild, moderate, and severe. Commonly, cut-offs for severe disease require a body surface area (BSA) involvement of ≥10% or a Psoriasis Area Severity Index (PASI) > 10. However, clinical experience challenges these traditional measures and requirements, as patients with less extensive psoriasis may have disease that severely impacts quality of life.

Objective

The objective of the present study was to further explore the extent of patient burden when psoriasis affects special locations.

Methods

A total of 69,190 individuals living in the U.S were invited to participate in a patient advocacy survey by telephone and or web interviews over the course of 3 years (2019-2021). The survey instrument consisted of validated patient-reported outcome measures, measuring disease-specific quality of life (Dermatology Life Quality Index, DLQI), depression (Patient Health Questionnaire (PHQ)-2 and (PHQ)-9), and the ability to participate in social roles and activities (PROMIS Ability to Participate in Social Roles and Activities (SF-4a). Chi-square tests were performed to explore association between psoriasis involvement on special locations and patient outcomes and multivariate logistic regression models were then constructed, to assess impact of having psoriasis on special locations patient outcomes, controlling for potential confounding factors.

Results

A total of 4129 individuals completed the survey. 3594 (84.4%) of patients surveyed reported psoriasis involving special areas of the bodysuch as the scalp, face, hands, feet, or genitalia. Involvement of special areas is associated with worse quality of life and depression. 35-71% of patients with 10% or less total BSA involvement experienced a moderate-to-extremely large effect on these life function domains. When adjusting for age, sex, and body surface area, psoriasis involvement of a special location was associated with poorer patient reported outcomes, including a 46% less likelihood of reporting their skin disease as having “no or only a small effect on QoL,” a 30% less likelihood of having a “normal l ability to participate in social roles and activities,” and a 126% higher likelihood of f having depression.

Conclusion

Real-world data presented here demonstrate that psoriasis involving special areas is associated with adverse life consequences, including poor quality of life and depression.

Keywords

psoriasis disease severity mental health quality of life treatment

Introduction

Psoriasis severity has traditionally been categorized as mild, moderate, and severe. Often, cut-offs for severe disease require a body surface area (BSA) involvement of >10%. or PASI>10.¹ Body surface area affected by psoriasis is predictive of developing psoriatic arthritis, diabetes, and premature mortality, independent of traditional risk factors for these outcomes and in a dose-response manner and is thus important in guiding patient management, however, it correlates only weakly with quality of life.^2-4 Indeed, a systematic review of randomized controlled trials showed that assessment of disease severity by BSA or Psoriasis Area Severity Index (PASI) scores may underestimate the impact of disease severity on overall quality of life.⁵ Consequently, there is a compelling need for reclassification of psoriasis disease severity that better ensures that patients are not under-classified and subsequently undertreated.

The International Psoriasis Council (IPC) recently published new guidance on how to best define psoriasis severity.⁶ Instead of using the commonly used terms of “mild, moderate, and severe” the IPC consensus states that “psoriasis patients should be classified as either candidates for topical therapy or candidates for systemic therapy; the latter are patients who meet at least one of the following criteria: 1) body surface area (BSA) > 10%; 2) disease involving special areas; or 3) failure of topical therapy.”⁶ One of the main drivers underlying this proposed change by psoriasis experts was the knowledge that under-classification of psoriasis severity (commonly done in clinical trials and in clinical practice) often results in undertreatment of patients. Typically, a minimum of 10% BSA involved with psoriasis is required for entry into psoriasis clinical trials of newer medications, leading to a lack of evidence regarding the efficacy and safety of these agents for patients with lower BSA involvement or disease involving special areas. This also results in national health systems and third-party payers declining reimbursements for psoriasis patients who do not have the required 10% minimum BSA involvement.

In real-world settings, selection of psoriasis therapy is not always constrained by standardized BSA limits since clinicians often consider other factors relevant to the patient experience. A key additional consideration involved in drug selection is the presence of psoriasis involving special areas, defined as psoriasis involving the scalp, face, palms/soles, genitalia, flexures, or nails. Psoriasis in these locations is often difficult to treat with topical therapies alone.^7-9 In addition, quality of life is usually more adversely affected when psoriasis involves the often visible special areas of the body.^10-12 However, a robust analysis as to what extent quality of life, emotional well-being, and social role interactions are impaired is lacking in patients with psoriasis involving special areas.

Our objective was to further explore in detail the frequency and extent of patient burden when psoriasis affects special areas. We collected and analyzed pooled data from participants surveyed by National Psoriasis Foundation (NPF) over the course of 3 years. More specifically, we focused on quality of life, depression, and the ability to participate in social roles (utilizing validated instruments) in patients with and without involvement of psoriasis in special areas.

Methods

Using a web-based survey and telephone interviews, the NPF annually conducts a cross-sectional study of a random stratified sample of individuals with psoriatic disease living in the U.S. Individuals living in the United States with a physician given diagnosis of psoriasis and/or psoriatic arthritis who contacted the NPF between 2017 and 2021 were identified from the Foundation’s database. These individuals were than randomized and stratified by disease type, sex, and geographic location to yield a participant database of ∼20,000 subjects in order to achieve a final sample of ∼1200 respondents estimating a 6% response rate. Stratification estimates were established using current psoriasis estimates in the adult population in the United States and U.S. Census data. (Armstrong, Mehta et al 2021) Participants provided written informed consentand received a $5 gift card for completing the survey. IRB approval was obtained (Genetic Alliance IRB, Protocol # NPF-ASP- 2019, NPF-ASP-2020-2, NPF-ASP-2021).

A total of 69,190 individuals were invited to participate in the survey over the course of 3 years (2019-2021). The survey instrument included of validated patient-reported outcome measures, measuring disease-specific quality of life (Dermatology Life Quality Index, DLQI), depression (Patient Health Questionnaire (PHQ)-2 and PHQ-9), and the ability to participate in social roles and activities (PROMIS Ability to Participate in Social Roles and Activities (SF-4a). With respect to quality of life a DLQI score ≤5 was regarded as no to small effect and DLQI score ≥6 as moderate to extremely large effect. Depression was measured using a tiered assessment process utilizing the PHQ-2 and PHQ-9. A score of 3 or higher on the PHQ-2 is indicative of depression. (Kroenke, Spitzer et al 2003) Individuals with PHQ-2 scores ≥3 then completed the PHQ-9 to assess severity of depression. With respect to social roles PROMIS t score ≤45 indicated some limitation and PROMIS t score >45 indicated normal ability. All data were patient reported and assessment by clinicians was not reported. Descriptive statistics were generated to describe the survey sample. Chi-square tests of independence (SPSS Ver 26) were conducted to explore association between involvement of psoriasis in special location and patient outcomes. Multivariate logistic regression analyses (STATA SE Ver 9) were then performed to explore impact of psoriasis involvement in special locations on patient outcomes, while controlling for age, sex, and disease severity – defined as body surface area at time of data collection. Age and disease severity were reported as continuous variables. Sex was coded dichotomously “male” = 1 and “female” = 0. Special locations were defined here as involvement of psoriasis of the scalp, face, hands/feet, flexures, genitalia, and nails.

Results

Patient Population

A total of 4129 individuals completed the survey, yielding a 6% response rate and a ±2 margin of error. Demographics, disease characteristics, and treatment histories for those psoriasis patients with or without involvement of special areas are shown in Table 1.

Table 1.

Demographics and Disease Characteristics of Survey Participants.

	Overall Population, n = 4129	No Special Area Involvement, n = 535 (15.6%)	Special Area Involvement, n = 3594 (84.4%)	X² test P-value
Mean age, years	54.3 (53.9-54.8)	58.1 (57.1-59.0)	53.7 (53.2-54.1)
Age 18-35	486 (11.7%)	34 (5.3%)	452 (12.9%)	P < .001
Age 36-50	1087 (26.2%)	138 (21.7%)	949 (27.0%)
Age 51-64	1474 (35.5%)	254 (39.9%)	1220 (34.7%)
Age 65+	1106 (26.6%)	211 (33.1%)	895 (25.5%)
Mean years with psoriasis	25.6 (25.1-26.1)	25.0 (23.5-26.5)	25.7 (25.2-26.2)
Male	1753 (41.6%)	296 (44.8%)	1457 (40.9%)	P = .066
Female	2466 (58.4%)	365 (55.2%)	2101 (59.1%)
BSA, mean (SD)	7.5% (±15.4)	3.2% (±7.6)	8.1 (±16.1)
≤10% BSA	3454 (85.7%)	443 (94.7%)	3011 (84.5%)	P < .001
>10% BSA	576 (14.3%)	25 (5.3%)	551 (15.5%)	P < .001
PsO-only	1932 (47.9%)	238 (50.9%)	1694 (47.6%)	P = .179
PsO and PsA	2098 (52.1%)	230 (49.1%)	1868 (52.4%)	P = .179
Biologics only	552 (14.2%)	133 (22.2%)	419 (12.7%)	P < .001
Oral systemics only	604 (15.5%)	108 (18.0%)	496 (15.1%)
Topicals only	1153 (29.6%)	124 (20.7%)	1029 (31.3%)
Other	87 (2.2%)	9 (1.5%)	78 (2.4%)
More than 1 therapy type	1493 (38.4%)	226 (37.7%)	1267 (38.5%)
BMI, underweight-normal	1190 (29.1%)	217 (34.1%)	973 (28.2%)	P < .01
BMI, overweight	1285 (31.5%)	195 (30.6%)	1090 (31.6%)
BMI, obese	1608 (37.7%)	225 (35.3%)	1383 (40.1%)
White	3624 (87.0%)	561 (86.7%)	3063 (87.0%)	P = .817
Nonwhite	542 (13.0%)	86 (13.3%)	456 (13.0%)	P = .817
Household income < $30,000	691 (19.3%)	79 (14.6%)	612 (20.2%)	P < .01
Household income $30,000 - $74,999	1245 (34.8%)	223 (41.1%)	1022 (33.7%)
Household income $75,000 and higher	1638 (45.8%)	241 (44.4%)	1397 (46.1%)

Association Between Involvement of Special Areas and Patient-Reported Outcomes

3594 (84.4%) of patients surveyed reported psoriasis involving special areas. Chi-square tests of independence were used to examine the relationship between involvement of psoriasis in special locations, age, sex, and disease severity on quality of life, depression, and ability to participate in social roles and activities. These results suggest that individuals with involvement of psoriasis in special locations experience (1) worse quality of life and (2) depression (Figure 1). Compared to individuals with no special area involvement, a higher percentage of individuals with psoriasis involvement of special areas reported their psoriasis had a moderate to extreme impact on quality of life (25.4% vs 45.4%, P < .001) and reported having depression (19.2% vs 26.8%, P < .001). Results from chi-square tests of independence did not suggest ability to participate in social roles and activities is associated with having psoriasis in special locations; individuals with psoriasis affecting special locations reported similar rates of experiencing some limitation in ability to participate in social roles and activities (44.3% vs 43.1%, P = .576).

Figure 1.

Psoriasis. Quality of Life (A), Depression (B), and the Ability to Participate in Social Roles and Activities (C) are Impaired with Involvement of Psoriasis in Special Areas. ***P < .001; †P = .576.

Results from chi-square tests of independence to examine the relationship between age, sex, and disease severity on dermatology-related quality of life, depression, and ability to participate in social roles and activities suggested that age, sex, and disease severity, are also associated with dermatology-related quality of life, depression, and ability to participate in social roles and activities (Figure 1). These results suggest that women, individuals under 40 years of age, and those with severe disease (BSA >10%) experience poorer outcomes compared to men, individuals 40 years or older, and those with moderate or mild disease (BSA ≤10%). Compared to men, women reported higher rates of their skin having a moderate to extreme impact on their quality of life (46.0% vs 38.7%, P < .001), higher rates of depression based on PhQ-2 score ≥3 (27.1% vs 23.3%, P < .01), and some limitation in their ability to participate in social roles and activities due to their psoriasis (50.0% vs 35.3%, P < .001).

The proportion of individuals reporting that their skin had a moderate to extreme impact on their quality of life, experience depression, and experience some limitation in their ability to participate in social roles and activities differed between individuals 40 years of age and under and those older than 40 years, based on Chi-square tests of independence. These results suggest that individuals 40 years of age and under are differently impacted by their psoriasis compared to those over the age of 40.

While Chi-square tests of independence suggest that special location involvement is associated with poorer outcomes among individuals with psoriasis, further analysis is needed to determine if the relationship between special location involvement and patient outcomes is maintained when age, sex, and disease severity are considered.

In order to explore the impact of special location involvement on patient outcomes while controlling for age, sex, and disease severity defined by body surface area, multivariate logistic regression analyses were conducted. Results from these analyses suggest that when controlling for age, sex, and body surface area, having psoriasis in special locations continued to be impactful to patients across these domains. Individuals with psoriasis involvement in special locations reported a 46% less likelihood that their skin disease had “no or only a small effect on QoL,” a 30% less likelihood of having a “normal ability to participate in social roles and activities,” and a 126% higher likelihood of having depression (Table 2). The Ability to Participate in Social Roles and Activities is Limited with Involvement of Psoriasis in Special Areas in Both Sexes with 10% or Less Total BSA (Supplemental Table 1).

Table 2.

Multivariate Logistic Regression Analysis of Impact of Psoriasis Involvement in Special Areas.

	Odds Ratio	95% CI	P-value
Normal ability to participate in social roles and activities
Special location involvement	.70	.56-.87	P < .01
BSA	.98	.97-.98	P < .001
Male	1.88	1.64-2.15	P < .001
Age	1.00	.99-1.00	P = .948
Skin no or small effect on QoL
Special location involvement	.54	.43-.69	P < .001
BSA	.96	.95-.96	P < .001
Male	1.34	1.16-1.55	P < .001
Age	1.02	1.02-1.03	P < .001
Depression likely
Special location involvement	2.26	1.67-3.06	P < .001
BSA	1.02	1.02-1.02	P < .001
Male	.86	.74-1.00	P = .06
Age	.99	.98-.99	P < .001

Discussion

In a large group of U.S. psoriasis patients surveyed over the span of 3 years, we show here that psoriasis involving special areas of the body, such as the scalp, face, hands, feet, flexures or genitalia, is associated with worse quality of life, depression, and greater limitation in ability to participate in social roles and activities. Importantly, the association between these adverse life effects and having psoriasis involvement of special location remained when controlling for age, sex, and disease severity.

Several recent publications lend further support for the impact of special area involvement to impairment of quality of life. In a cross-sectional quantitative web-based survey in the North America, Europe, Japan (the UPLIFT survey) patients with psoriatic disease reported high disease burden. For 60% of patients in this survey with “limited disease” (BSA less than 3 involved palms) and involvement of at least one special area the disease severity was self-reported as moderate or severe. Noteworthy was that in this group of patients the mean DLQI was 9.4, an impact not dissimilar from that seen in “moderate-to-severe” patients enrolled in clinical trials.¹³ The present study and the available literature converge on the conclusion that most patients with psoriasis have disease present in special areas, which has a substantial impact on quality of life.

Individuals living with psoriasis with less than 10% total BSA are often treated with topical therapies alone, even if they have psoriasis involving special areas. This is sometimes due to the common BSA requirement of 10% or more that is normally required by insurance and regulatory authorities for psoriasis patients to receive systemic therapies. Data presented here clearly demonstrate the detrimental life effects caused by psoriasis when it involves special areas while controlling for disease severity. Thus, we suggest that patients with psoriasis involving special areas should warrant consideration of the full array of available psoriasis treatments, especially those systemic treatments typically reserved for individuals with 10% BSA involvement or more.

Indeed, some clinical studies with systemic agents have been performed in psoriasis patients with less than 10% BSA and/or in patients with psoriasis involving special areas. For example, apremilast was studied in patients with less than 10% BSA.¹⁴ These patients responded similarly to patients with baseline BSA of 10% or more.¹⁴ Regarding special area involvement, ixekizumab, an anti-IL-17A biologic therapy, was studied in patients with moderate-to-severe genital psoriasis;⁷40% of patients in this trial had a total BSA of less than 10%. Patients with and without 10% total BSA involvement had similar improvements in genital psoriasis disease severity and quality of life with ixekizumb.⁷

Limitations of this report include the low survey completion rate and a sample consisting of individuals engaged with a patient advocacy organization, which may contribute to selection bias. Treatment status was also not objectively described. Finally, some survey items had not undergone psychometric testing, and the survey sample may not be representative of the estimated psoriatic patient population. The survey did not collect data on which specific special areas were involved and how they affected the survey results. Another limitation of the study is that it did not control for history of psychiatric illness such as depression or anxiety.

In summary, real-world data presented here demonstrate that psoriasis involving special areas is associated with adverse life consequences, including poor quality of life, depression, and ability to participate in social roles and activities even while controlling for age, sex, and disease severity in terms of BSA. The new IPC disease severity consensus statement for psoriasis includes patients with disease involving special areas as candidates for systemic therapy, on the same level as patients with BSA involvement of 10% or more.³ This analysis documents the negative impact of psoriasis involving special areas and hopefully will lead to more appropriate treatment of patients suffering from psoriasis, consistent with recent expert guidelines.

Supplemental Material

Supplemental Material - Psoriasis Involving Special Areas is Associated with Worse Quality of Life, Depression, and Limitations in the Ability to Participate in Social Roles and Activities

Supplemental Material for Psoriasis Involving Special Areas is Associated with Worse Quality of Life, Depression, and Limitations in the Ability to Participate in Social Roles and Activities by ndrew Blauvelt, MD, MBA, George C. Gondo, MA, Stacie Bell, PhD, Cristina Echeverría, MD, Marcus Schmitt-Egenolf, MD, PhD, Lone Skov, MD, Peter van de Kerkhof, MD, PhD, Leah McCormick Howard, Bruce Strober, MD, PhD in Journal of Psoriasis and Psoriatic Arthritis

Footnotes

Acknowledgments

The authors wish to acknowledge Matthias Augustin for helpful discussion.

Author Contributions

George Gondo: employee of the National Psoriasis Foundation; Stacey Bell: employee of the National Psoriasis Foundation at the time of this work; Cristina Echeverría: advisor and/or speaker and/or principal investigator for AbbVie, Janssen, Pfizer, Novartis, Sandoz, Amgen, Sanofi Genzyme, UCB and Eli Lilly; Marcus Schmitt-Egenolf: responsible for dermatology in the project management for the national guidelines for psoriasis at the Swedish Board of Health and Welfare; Lone Skov: has served as an advisor for AbbVie, Novartis, Almirall, LEO Pharma, Pfizer, Bristol-Myers Squibb, Boehringer Ingelheim, UCB, Eli Lilly, and Sanofi-Genzyme, and served as a speaker for AbbVie, LEO Pharma, Pfizer, Novartis, Abbvie, and Sanofi-Genzyme, and received research grants from Leo Pharma, Janssen-Cilag, Bristol-Myers Squibb, UCB, and Sanofi-Genzyme; Peter CM van de Kerkhof: Chief medical officer of the International psoriasis council, served as consultant and or has given lectures lecturers sponsored by Almirall, Abbvie, Eli Lilly, Novartis, Janssen Pharmaceutica, Leo Pharma, Bristol Mayer Squib, UCB, Boehringer Ingelheim and Dermavant; Leah McCormick Howard: employee of the National Psoriasis Foundation; Bruce Strober: Consultant (honoraria): AbbVie, Alumis, Almirall, Amgen, Arcutis, Arena, Aristea, Asana, Boehringer Ingelheim, Immunic Therapeutics, Bristol-Myers-Squibb, Connect Biopharma, Dermavant, Evelo Biosciences, Janssen, Leo, Eli Lilly, Maruho, Meiji Seika Pharma, Mindera Health, Novartis, Pfizer, UCB Pharma, Sun Pharma, Regeneron, Sanofi-Genzyme, Union Therapeutics, Ventyxbio, vTv Therapeutics; Speaker: AbbVie, Arcutis, Dermavant, Eli Lilly, Incyte, Janssen, Regeneron, Sanofi-Genzyme; Scientific Co-Director (consulting fee): CorEvitas Psoriasis Registry. Investigator: Dermavant, AbbVie, CorEvitas Psoriasis Registry, Dermira, Cara, Novartis. Editor-in-Chief (honorarium): Journal of Psoriasis and Psoriatic Arthritis.

Declaration of Conflicting Interest

Andrew Blauvelt: speaker/received honoraria from AbbVie and UCB, served as a scientific adviser/received honoraria from AbbVie, Abcentra, Aligos, Almirall, Amgen, Anaptysbio, Arcutis, Arena, Aslan, Athenex, Boehringer Ingelheim, Bristol-Myers Squibb, Dermavant, EcoR1, Eli Lilly and Company, Evommune, Forte, Galderma, HighlightII Pharma, Incyte, Janssen, Landos, Leo, Merck, Novartis, Pfizer, Rapt, Regeneron, Sanofi Genzyme, Spherix Global Insights, Sun Pharma, TrialSpark, UCB Pharma, Vibliome, and Xencor, and has acted as a clinical study investigator/institution has received clinical study funds from AbbVie, Amgen, Arcutis, Athenex, Boehringer Ingelheim, Bristol-Myers Squibb, Dermavant, Eli Lilly and Company, Galderma, Incyte, Janssen, Leo, Merck, Novartis, Pfizer, Regeneron, Sun Pharma, and UCB Pharma. George Gondo: employee of the National Psoriasis Foundation. Stacey Bell: employee of the National Psoriasis Foundation at the time of this work. Cristina Echeverría: advisor and/or speaker and/or principal investigator for AbbVie, Janssen, Pfizer, Novartis, Sandoz, Amgen, Sanofi Genzyme, UCB and Eli Lilly. Marcus Schmitt-Egenolf: responsible for dermatology in the project management for the national guidelines for psoriasis at the Swedish Board of Health and Welfare. Lone Skov: has served as an advisor for AbbVie, Novartis, Almirall, LEO Pharma, Pfizer, Bristol-Myers Squibb, Boehringer Ingelheim, UCB, Eli Lilly, and Sanofi-Genzyme, and served as a speaker for AbbVie, LEO Pharma, Pfizer, Novartis, Abbvie, and Sanofi-Genzyme, and received research grants from Leo Pharma, Janssen-Cilag, Bristol-Myers Squibb, UCB, and Sanofi-Genzyme. Peter CM van de Kerkhof: Chief medical officer of the International psoriasis council, served as consultant and or has given lectures lecturers sponsored by Almirall, Abbvie, Eli Lilly, Novartis, Janssen Pharmaceutica, Leo Pharma, Bristol Mayer Squib, UCB, Boehringer Ingelheim and Dermavant. Leah McCormick Howard: employee of the National Psoriasis Foundation. Bruce Strober: Consultant (honoraria): AbbVie, Alumis, Almirall, Amgen, Arcutis, Arena, Aristea, Asana, Boehringer Ingelheim, Immunic Therapeutics, Bristol-Myers-Squibb, Connect Biopharma, Dermavant, EPI Health, Evelo Biosciences, Janssen, Leo, Eli Lilly, Maruho, Meiji Seika Pharma, Mindera Health, Novartis, Ono, Pfizer, UCB Pharma, Sun Pharma, Regeneron, Sanofi-Genzyme, Union Therapeutics, Ventyxbio, vTv Therapeutics.

• Stock Options: Connect Biopharma, Mindera Health

• Speaker: AbbVie, Eli Lilly, Incyte, Janssen, Regeneron, Sanofi-Genzyme

• Scientific Co-Director (consulting fee): CorEvitas (formerly Corrona) Psoriasis Registry

• Investigator: Dermavant, AbbVie, CorEvitas Psoriasis Registry, Dermira, Cara, Novartis

• Editor-in-Chief (honorarium): Journal of Psoriasis and Psoriatic Arthritis

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

Consent

Participants provided written informed consent.

Ethics

IRB approval was obtained (Genetic Alliance IRB, Protocol # NPF-ASP-2019, NPF-ASP-2020-2, NPF-ASP-2021).

ORCID iDs

George C. Gondo

Stacie Bell

Peter van de Kerkhof, MD

Bruce Strober, MD

Supplemental Material

Supplemetal material for this article is available online.

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