Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) encompasses three diseases: granulomatosis with polyangiitis (formerly Wegener's granulomatosis) (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (formerly Churg-Strauss syndrome) (EGPA). AAV mainly affects small blood vessels such as small arteries, arterioles, capillaries, and venules. The clinical presentation varies depending on the organs affected, with the lungs and kidneys being the most commonly involved.1 AAV is rare, with a global incidence and prevalence of 13 to 20 cases per million people and 46 to 184 cases per million people, respectively. In Peru, the incidence of AAV was 4.01/million for MPA, .50/million for GPA, and .14/million for EGPA.2,3 AAV had a female: male ratio of 2.1:1 and was 7.1 times more common in people over 50.3 However, there is variability in terms of race and geographical regions, with Caucasians being the most affected; likewise, European and Nordic countries have a higher number of cases.2

The prognosis for AAV varies depending on the subtype and response to treatment. Five-year survival rates for AAV range from 47% to 90%, depending on the subtype.4 Despite this improvement in survival rates, one-third of patients will experience irreversible damage.5 Due to the improved prognosis, patients with AAV are focusing on understanding the impact of their disease and/or treatment on their psychological wellbeing, family, and/or work life. Therefore, it is important to assess health-related quality of life (HRQoL) in patients with AAV, as this can be significantly impacted by the chronic nature of the disease and associated complications such as renal failure and infections, as well as by treatment and relapses.6,7 Various instruments have been developed to measure HRQoL, including the Short Form-36 Health Survey (SF-36) questionnaire. This questionnaire contains 36 questions across the domains: emotional role (ER), vitality (VT), social role (SR), bodily pain (BP), physical role (PR), physical functioning (PF), general health (GH), and mental health (MH).8

Although there are studies that have evaluated HRQoL in AAV patients, mainly in European and North American countries,9,10 there is little information on its associated factors. Therefore, the objective of this study is to determine the factors associated with HRQoL in patients with AAV treated at the Guillermo Almenara Irigoyen National Hospital.

Data were taken from the Almenara Vasculitis Cohort, which is a prevalent cohort of AAV patients that began in December 2022. Patients in the cohort attend quarterly visits during which laboratory tests and imaging are performed, and various questionnaires are completed by the patients (self-reported), including one on HRQoL. At each visit, the evaluating physician also completes the Birmingham Vasculitis Activity Score version 3 (BVASv3) and the Vasculitis Damage Index (VDI). This study was developed using an observational, analytical, cross-sectional design through the review of medical records. Patients over 18 years of age who met the American College of Rheumatology/European League Against Rheumatism (ACR/EULAR 2022) classification criteria for MPA, GPA, and EGPA11–13 were included. Patients who expressly refused to participate in the study and those who were illiterate were excluded.

Sociodemographic and clinical characteristics were evaluated. These included sex, age, marital status, race, employment status, socioeconomic status (as measured by the Graffar scale14), disease duration, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) levels. Disease activity was measured using the BVASv3 questionnaire.15 Cumulative damage was measured using the VDI questionnaire.16 AAV subtype was categorised as GPA, MPA, or EGPA. ANCA subtype was determined using either immunofluorescence (p-ANCA, c-ANCA, or negative) or ELISA (MPO, PR3, or negative). Disease status was categorised as active, relapse, or remission. Prednisone use and current prednisone dose were also considered, as was the use of immunosuppressants (IS) and the type of current IS (cyclophosphamide [CYP], rituximab [RTX] or others). Active disease was defined as BVASv3 score ≥1. Quality of life was assessed using the SF-36 questionnaire, across eight domains (PR, VT, PF, BP, ER, SR, GH, and MH) and two composite dimensions (physical component summary [PCS] and mental component summary [MCS]). Scores range from 0 to 100, with a cut-off point of 50; higher scores indicate better quality of life.8

A total of 55 patients were evaluated, and their sociodemographic and clinical characteristics are presented in Table 1. The majority were female (74.6%). The mean age was 58.8 years (SD 13.5), and the mean disease duration was 5.8 years (SD 5.2). The most common type of vasculitis was MPA (65.5%). The BVASv3 and VDI scores were 6.14 (9.1) and 2.3 (1.7), respectively. Twenty-seven patients (49.1%) had active disease.

The univariate and MV analyses are shown in Supplementary Tables 1 and 2, respectively. Regarding the MV analysis, it was observed that male sex was associated with better GH (B = 11.06; p = .012), PR (B = 22.92; p = .023), VT (B = 18.59; p ≤ .001), PF (B = 19,45; p = .005), MH (B = 15.44; p = .003), PCS (B = 14.58; p ≤ .001), and MCS (B = 12.23; p = .008). Similarly, treatment with IS other than RTX and CYP and patients who were employed were associated with better ER ([B = 23.94; p = .037] and [B = 22.58; p = .024], respectively). The EGPA subtype was associated with better VT (B = 28.60; p = .009). On the other hand, age and ESR level were associated with poorer PF ([B = −.68; p = .003] and [B = −.22; p = .029], respectively). Low socioeconomic status was associated with poorer GH and PCS ([B = −12.37; p = .021] and [B = −10.78; p = .038], respectively) and medium socioeconomic status was associated with poorer GH (B = −11.58; p = .012).

It is important to note that no relationship was observed between disease activity (measured by BVASv3) and HRQoL. Similarly, no relationship was found between cumulative damage (measured by VDI) and HRQoL.

The objective of this study was to determine the factors associated with HRQoL in adult patients with AAV. We found that the associated factors were male sex, employment, the EGPA subtype, a high socioeconomic status, the use of IS other than CYP and RTX, and ESR level.

HRQoL has been assessed in different autoimmune diseases; however, there are limited data on this in vasculitis, particularly in AAV.17 It is now known that patients with AAV have an impaired quality of life due to situations such as anxiety, depression, fatigue, and pain.9,18 It is also is very important to note that a poorer quality of life may be associated with mortality.19 For this reason, assessing HRQoL in patients with AAV is relevant, as we proposed in our study.

Among the findings obtained, a direct correlation was observed between male gender and various dimensions of the SF-36, such as GH, PR, PF, MH, and VT, including MCS and PCS. These findings have been reported in several studies on both vasculitis and other autoimmune diseases, such as rheumatoid arthritis.20 For example, Robson et al., in 2018, evaluated 626 patients with AAV using the ANCA-associated vasculitis patient-reported outcomes (AAV-PRO) questionnaire, revealing that women had higher scores in different domains, indicating poorer HRQoL.21 Similarly, Hurtado-Arias et al., in 2023, evaluated 70 patients with AAV using the AAV-PRO questionnaire and found that women had higher scores in the treatment side effects domain.22 On the other hand, in the study by Reinhold-Keller et al., conducted in 2002 in 60 patients with GPA, it was observed that although AAV impacts employment, this is more significant in women, who have an almost 3-fold risk higher risk of losing their jobs.18

Regarding PF, an inverse relationship with age was observed, which is consistent with findings from other studies. In a 2022 study by Nic an Riogh et al., which evaluated 374 patients with AAV using the EuroQol-5D questionnaire (which assesses HRQoL through five domains), it was found that for each additional year of life, the score on this questionnaire decreased by 2.7%, indicating poorer HRQoL.23 Similarly, Robson et al. (2018) evaluated 50 patients with AAV and found that 90% of them had physical limitations that impeded daily activities such as bathing or washing their hands. This was more significant with increasing age.10 Similarly, a 2011 study by Walsh et al. evaluated 346 patients with AAV and found that advanced age was associated with low PF.9 In a study by Faurschou et al. (2010) which included 68 patients diagnosed with GPA, it was found that those aged >58 years had significantly lower PCS and MCS scores.24

In terms of socioeconomic status, low and medium levels were found to be inversely related to GH. This finding is corroborated by other studies. For example, Floyd et al. found that patients with AAV experience significant economic losses due to unemployment and reduced income following diagnosis, which has a greater impact on socioeconomic status.17 Similarly, Franco-Aguirre et al. evaluated 112 patients with rheumatoid arthritis in 2015 and found social function to be impacted in patients with low socioeconomic status.25

Similarly, a direct association was found between ER and employment status. This is supported by the results of a study conducted by Reinhold-Keller et al., who found that unemployed patients experienced a significant reduction in HRQoL.18 Similarly, in 2017, Benarous et al. evaluated 189 patients diagnosed with AAV using the SF-36 and found that 33% of them were unemployed, and claimed this affected their mental health. This was reflected in lower scores in the ER domain. Furthermore, 50% of these patients associated their difficulty in finding work with their disease and/or sequelae.26

Our study also showed that patients who received treatment with IS other than CYP and RTX had better HRQoL in the ER domain. This may be because both RTX and CYP are usually indicated in cases of severe disease or relapses, meaning these patients may have had a lower baseline HRQoL due to disease activity. However, contrary to our findings, Parvova et al., in 2024, in 12 Bulgarian patients with GPA, found that treatment with RTX leads to qualitative and quantitative improvement in all components of physical, mental, and social health.27 Similarly, a 2016 study conducted by Pugnet et al., comparing the use of RTX and azathioprine in 115 patients with AAV, showed that the use of azathioprine was associated with a marked decrease in physical functioning according to the SF-36.28 Given the conflicting results between our study and those reported, further studies with larger populations are recommended to clarify this discrepancy.

An inverse relationship was also observed between ESR and PF. This may be because active disease elevates acute phase reactants and affects quality of life due to drug use and organ involvement. This has also been reported in a 2024 study by Ahn et al., who evaluated 189 AAV patients using the SF-36 questionnaire and found an inverse association between ESR and PCS.19 However, Sreih et al. (2013) evaluated 51 patients with various vasculitides, including AAV, and found no correlation between fatigue, pain, functional disability, BVAS, VDI, or ESR.29

Of the AAV subtypes, only EGPA was directly related to VT. One possible explanation for this is that patients with EGPA tend to experience fewer vasculitic complications and more allergic reactions. This implies that they use fewer corticosteroids and immunosuppressants, such as rituximab (RTX) and cyclosporine (CYP), than patients with other AAV subtypes. This would have a positive impact on HRQoL. Similarly, Basu et al. (2018) point out that GPA and MPA have a similar pathophysiology, resulting in comparable treatment responses and prognoses. These are significantly lower than those of patients with EGPA, who have a better prognosis and therefore better HRQoL.30

In our study, however, we found no relationship between disease activity, cumulative damage, and HRQoL. These findings are consistent with those of the systematic review by Floyd et al., which found that 86% of studies showed no significant correlation between SF-36 components, BVAS, and VDI.17

Our study has some limitations. Firstly, being a single-centre study with a predominantly mestizo population, the results cannot be generalised to other ethnic groups or regions. Secondly, the number of patients enrolled in the study was low (n = 55). Thirdly, the SF-36 questionnaire is generic and may not fully represent the impact of AAV on patients' HRQoL. However, the SF-36 has been used to assess HRQoL in other systemic autoimmune diseases and in the vast majority of studies on HRQoL in AAV. Although Robson et al. have developed a new questionnaire specific to patients with AAV (AAV-PRO), it has not yet been validated in the Peruvian population.21 Fourthly, as this was a non-randomised sample, our results probably cannot be generalised to public centres. Furthermore, due to our study design, we cannot infer causality from the findings. On the other hand, our study has several strengths. First, it addresses a topic of great clinical and social importance, given that vasculitis is a chronic disease that can significantly impact patients' physical and emotional well-being. Assessing the impact of these conditions on HRQoL improves our understanding of the needs and difficulties of this population and contributes to better care and management. Second, the research was conducted in a national referral hospital, ensuring that the sample included patients from different regions of the country and providing a broader, more representative view of the impact of vasculitis on patients' HRQoL in different geographical and socioeconomic contexts. Third, this study is one of the few to have been conducted on a Latin American population, as most studies focus on European patients.

In conclusion, this study showed that better HRQoL was associated with male sex, having EGPA, and being treated with IS other than RTX and CYP, while worse HRQoL was associated with older age, low socioeconomic status, and high ESR.

The Almenara Vasculitis Cohort was approved by the Ethics and Research Committee of the Guillermo Almenara Irigoyen National Hospital (161-CIEI-OlyD-GRPA-ESSALUD-2020).