Psoriatic arthritis poses a considerable burden to both individuals and healthcare systems, as evidenced by our study findings. This study aimed to assess the participant-reported humanistic and economic burden of PsA, relative to participants’ perceptions of condition severity and race/ethnicity. As expected, our results showed that self-reported moderate/severe PsA was associated with significantly worse health outcomes than self-reported mild PsA. However, in the context of race/ethnicity, we noted variation in health outcomes. Specifically, non-Hispanic Black participants reported significantly more absenteeism and activity impairment, and lower HCP and rheumatologist visits than non-Hispanic white participants. Moreover, the influence of perceived PsA severity on depression, HRQoL, and HCRU depended on race/ethnicity, particularly among non-Hispanic white participants. Notably, self-reported moderate/severe PsA was associated with greater odds of depression, lower SD-6D, and more ER visits specifically among non-Hispanic white participants.

Psoriatic arthritis is associated with substantial humanistic and economic burden [7, 20, 31,32,33,34,35,36,37,38,39,40]. Worsening of individual symptoms and manifestations of PsA are associated with reduced general and PsA-specific quality of life [39,40,41,42]. Considering self-reported severity is crucial for understanding disease burden. While we used perceived PsA severity in this study rather than a more objective clinical measure, we posit that patients’ perception of their disease severity is uniquely important, and our study supports the notion that patients’ perceived PsA severity is independently related to their disease burden. Symptoms identified as most problematic by patients (i.e., painful, inflamed, or broken skin) may not be considered the most bothersome by physicians, highlighting a potential discordance in physician and patient perceptions of PsA symptoms and their impact [43]. Our findings are among the first to show that participants with self-reported moderate/severe PsA reported significantly worse HRQoL scores and greater work and activity impairment than participants with mild PsA. Mean differences in HRQoL measures of PCS and EQ-5D-5L between participants with perceived moderate/severe and mild PsA exceeded clinical significance or established minimal clinically important differences [44, 45], demonstrating the negative impact of PsA severity on HRQoL. Participants with perceived moderate/severe PsA also reported more HCP and rheumatologist visits than those with perceived mild PsA and accumulated more annual direct and indirect medical costs. Our findings are echoed by several studies that demonstrated the detrimental impact of PsA manifestations on HRQoL, functional status, and work productivity using more objective measures of PsA severity [41, 42]. Concomitant presence of multiple PsA symptoms/manifestations and worse functional status have also been shown to be associated with greater healthcare resource use and costs [46, 47]. Existing literature, coupled with the results of our study based on participant-perceived disease severity, suggest individuals with moderate/severe PsA represent an underserved population with substantial unmet needs. Still, we recognize that our measure of PsA severity may not fully reflect the clinical severity of their disease and may be confounded by other socio-emotional and/or health considerations.

There is a paucity of data on racial and ethnic disparities in patients with PsA with respect to PROs, including HRQoL, WPAI, and economic outcomes. In our study that sought to quantify the humanistic and economic burden of PsA by measuring 21 PROs, self-reported moderate/severe disease was associated with worse burden than self-reported mild disease across all race/ethnic groups evaluated. Of note, our results suggest non-Hispanic Black participants may experience greater absenteeism and overall activity impairment than other race/ethnicity groups. Non-Hispanic Black participants also reported fewer HCP and rheumatologist visits over the past 6 months in our study, even after adjusting for disease severity. Barriers to access to care among non-Hispanic Black patients could prevent adequate and timely treatment of PsA, potentially leading to less controlled disease and increased interference with workplace productivity and activity [17, 48]. Efforts to improve access to care are needed to achieve better outcomes for patients of minority racial/ethnic groups.

Our findings among non-Hispanic Black patients differed from that reported by Ogdie et al. [49], which showed similar rates of rheumatologist visits across race/ethnicity groups with PsA by insurance coverage. It is important to note that it is difficult to make apples-to-apples comparisons between studies given differences in the datasets used, study methods, and participant populations. Specifically, the Ogdie study was descriptive in nature and did not conduct any statistical analyses to identify differences between race/ethnicity groups. And as a claims-based analysis, patients insured with Medicare other than Medicare Advantage or the uninsured were not included. In contrast, the current study conducted statistical comparison between race/ethnicity groups and adjusted for potentially confounding variables across these groups. While the NHWS dataset was designed to be nationally representative of the general US population, and not for any specific disease cohort, participants were not restricted on the basis of presence or type of coverage. Therefore, our study provides unique information on how patient experiences may compare between race/ethnicity groups and additional perspectives for patients who are frequently excluded from clinical studies relying on other secondary data sources such as claims data.

Evidence suggests that non-Hispanic Black, Asian, and Hispanic populations are approximately 40% less likely to see a dermatologist for psoriasis than non-Hispanic white individuals [50]. The clinical presentation of psoriasis in skin of color can contribute to delayed diagnosis and greater disease severity, leading to untreated or undertreated disease [14, 15, 51]. Additionally, among individuals with newly diagnosed PsA, time to treatment initiation is significantly longer among non-Hispanic Black patients than among non-Hispanic white patients [17]. Other factors that may impact access to care include skepticism about the effectiveness of clinicians, perception of symptom severity, satisfaction with current treatment, and financial- or insurance-related issues [42]. For instance, Hispanic patients with lighter skin tones may exhibit symptoms more congruent with those of non-Hispanic white patients, potentially facilitating timely diagnosis and adequate care. To comprehensively understand these nuances, future analyses should incorporate factors such as socioeconomic status, cultural variation, and regional influences.

Our moderation analyses suggest that the influence of perceived PsA severity on outcomes may vary across race/ethnicity groups. Specifically, our results show that race/ethnicity moderated the relationship between self-reported PsA severity and mental health, such that moderate/severe PsA was associated with a greater odds of having moderate/severe depression compared to mild PsA, but only among non-Hispanic white participants. For all other racial/ethnic groups, we found no evidence of a significant association between perceived PsA severity and depression status. It is unclear why more severe PsA would be linked to poorer mental health among one racial/ethnic group, but not others. While the prevalence of depression is lower among non-Hispanic Black individuals than non-Hispanic white individuals in the USA, rates of depression differ when accounting for ethnicity and immigration status [52, 53]. Further, current instruments used to assess mental health may not adequately capture the experiences of non-Hispanic Black individuals [53]. Similarly, the prevalence of major depression differs among Hispanic ethnic subgroups, despite having similar lifetime prevalence of depressive disorder as non-Hispanic whites overall [53,54,55]. Cultural beliefs around the existence and causes of mental health issues may influence the observed disparity in prevalence [53]. The complex relationship between familial, contextual, and social factors, as well as other factors such as age of arrival in the USA, degree of acculturation, and language proficiency, may influence the risk of mental health issues such as depression.

Our results also suggest that race moderates the interaction between disease severity and ER visits. Healthcare resource use in individuals with PsA is high, irrespective of disease severity [38]. In a matched analysis of patients with and controls without PsA and psoriasis, the rate of annual ER visits and the proportion of patients with ER visits were higher among patients with PsA [38]. Additionally, racial/ethnic differences in ER visits, although not specific to PsA, are well documented. According to the National Center for Health Statistics, in 2021, non-Hispanic Black individuals had the highest overall ER visit rate, at double that for non-Hispanic white and Hispanic individuals [56]. These higher rates of ER visits among non-Hispanic Black people have been previously attributed to receiving routine healthcare in the emergency department [57,58,59]. Our findings show that non-Hispanic white participants with self-reported moderate/severe PsA reported more frequent ER visits than those with self-reported mild PsA, whereas non-Hispanic Black and Hispanic people with self-reported moderate/severe PsA reported a reduction in the rate of ER visits compared with those with self-reported mild PsA, though the estimates were not significant. While the results for non-Hispanic white participants align with expectations for more severe PsA, the observed trends in non-Hispanic Black and Hispanic groups raise the need for further investigation. It is possible that the increase in ER visits among non-Hispanic white participants is attributable to impaired mental health and HRQoL rather than PsA severity, which might suggest that those with more severe disease are more likely or willing to seek healthcare [60] or have access to more healthcare resources, the latter of which is supported by the greater overall HCP visits among those with self-reported moderate/severe PsA observed in this analysis. These results provide insights on racial/ethnic differences in outcomes and propose variations in self-perception of PsA severity based on race/ethnicity (i.e., people of color may underestimate the severity of their disease or overestimate their mental health). Future efforts exploring nuances within non-Hispanic Black and Hispanic populations and/or using more objective measures of condition severity may help to better understand these results.

Our study had several strengths, including the use of PROs, which provide participant perspectives on disease outcomes over third-party perceptions of disease burden. Racial/ethnic PRO data collection can aid in understanding the impacts of PsA and help inform clinical care. Further, this study used NHWS data, and provides PRO data on a diverse group of participants with PsA. The extensive roster of outcomes assessed in this study provides a robust contribution to the literature on a variety of PROs, increases the validity of the study findings through consistency across measures, and contributes to a holistic understanding of patient burden in PsA.

Limitations of this study include the self-reported nature of race/ethnicity and disease severity, which could not be independently verified [61,62,63]. Because race and ethnicity are social constructs that categorize people on the basis of perceived shared physical traits and culture [64], self-reporting of race/ethnicity is generally considered the gold standard [65,66,67]. And, while potentially confounding covariates were adjusted for in multivariable analyses, participant perception of disease severity may differ even with known clinical and social characteristics being equal. Another limitation was the relatively small sample sizes of non-Hispanic Black and Hispanic groups, despite pooling data across three survey years. Additionally, other than non-Hispanic white, non-Hispanic Black, and Hispanic groups, participants of all other races/ethnicities were included in the “Other” category, limiting the conclusions we could draw from our study. The survey was conducted in English within a virtual setting and may therefore introduce selection bias, as non-English-speaking individuals and individuals not appropriately targeted by a web-based survey could be underrepresented in our sample [68]. The study population was also generally more educated and affluent than historical national averages and may not therefore be reflective of the overall PsA population within the USA, as the use of data from the NHWS dataset was designed to be nationally representative of the general US population, and not for any specific disease cohort. The study sample may also not be representative of the diverse Hispanic population in the USA, as the proportion of uninsured Hispanics in our dataset contrasted with 2022 US Census data [69]. Notably, the NHWS dataset did include participants with diverse experiences and sociodemographic characteristics such as patients who were uninsured and, therefore, frequently omitted from secondary data analyses using real-world data. Further, cost data may underestimate the financial impact in the current post-COVID era, as medical costs were calculated using 2018 data. Additionally, residual confounding may have biased multivariable models, despite attempts to adjust for other potential explanatory variables. As a result of the cross-sectional nature of the study, causal inference was not possible.