|Ahead of print publication
Impaired mobility drives disability in psoriatic arthritis – An observational study from Karnataka Psoriatic Arthritis Cohort (KPsAC)
Vineeta Shobha1, Chanakya Kodishala1, S Chandrashekara2, Sharath Kumar3, Vikram Haridas4, Vijay Rao5, Ramesh Jois6, Manisha Daware7, Yogesh Preet Singh5, Shweta Singhai8, BG Dharmanad6, Pramod Chebbi9, R Subramanian10, Ashwini Kamath11, Uma Karjiigi12, Vikramraj K Jain13, Chethana Dharmapalaiah14, Shiva Prasad15, C Srinivas16, J Ramya1, Benzeeta Pinto1, Beenish Nazir2, Harshini17, Mahendranath18
1 Department of Clinical Immunology and Rheumatology, St. John's Medical College Hospital, Bengaluru, India
2 Chanre Rheumatology and Immunology Research Centre, Bengaluru, India
3 Columbia Asia Hospital, Bengaluru, India
4 Arthritis Specialty Clinic, Hubli, India
5 Department of Rheumatology, Manipal Hospitals, Bengaluru, India
6 Vikram Hospital, Bengaluru, India
7 Narayana Health City, Bengaluru, India
8 Sakra Hospital, Bengaluru, India
9 SDM Medical College, Dharwad, India
10 JSS Medical College, Mysore, India
11 Yenepoya Specialty Hospital, Managlore, India
12 Department of Rheumatology, Apollo Hospital, Bengaluru, India
13 Department of Clinical Immunology and Rheumatology, Mahaveer Jain Hospital, Bengaluru, India
14 Department of Rheumatology, Aster CMI Hospital, Bengaluru, India
15 Apollo BGS Hospital, Mysore, India
16 Fortis Hospital, Bengaluru, India
17 Sparsh Hospital, Bengaluru, India
18 Samarpan Health Centre, Bengaluru, India
|Date of Submission||23-Dec-2021|
|Date of Acceptance||19-Jun-2022|
|Date of Web Publication||18-Aug-2022|
Department of Clinical Immunology and Rheumatology, St John's Medical College Hospital, Sarjapur Road, Bengaluru - 560 034, Karnataka
Source of Support: None, Conflict of Interest: None
Introduction: Psoriatic arthritis (PsA) is a chronic inflammatory disease with significant functional impairment. Health Assessment Questionnaire-Disability Index (HAQ-DI) is a reliable and validated outcome measure for a variety of arthritides including PsA.
Objective: The objective of this study was to assess the disability as an outcome measure in PsA using the Indian version of HAQ (I-HAQ).
Methods: The I-HAQ was administered to PsA patients diagnosed as per the Classification Criteria for PsA. The I-HAQ comprises 12 questions (nine basic and three advanced activities of daily living (ADLs), on the standard HAQ format) relevant to the Indian population.
Results: In the 549 participants, the mean I-HAQ was 0.31 (0.45) and 48.2% had mild-to-moderate disability (I-HAQ>0–1). Female gender, older age, higher skin, joint scores, and Disease Activity Index for PsA were associated with some disability (I-HAQ>0). Symmetric polyarthritis (0.34) and spondyloarthritis (0.32) had a significantly higher disability compared to other subsets. Analyzing the individual questions of I-HAQ, squatting in the toilet or sitting cross-legged on the floor (r = 0.78), walking 3 km (r = 0.77), and climbing a flight of stairs (r = 0.74) correlated maximally to the total I-HAQ. ADL which was affected most frequently was “climbing a flight of stairs.” I-HAQ was significantly lower in patients who had been on disease-modifying antirheumatic drugs for 6 months or more (P = 0.0001).
Conclusions: The Indian version of HAQ-DI could be efficiently employed to assess outcomes in our cohort. Nearly half of the cohort had mild-to-moderate disability suggesting a high burden of inflammation. Higher joint activity scores are strongly associated with disability.
Keywords: Health Assessment Questionnaire-Disability Index, Health Assessment Questionnaire-Disability Index India, patient global assessment, patient-reported outcomes, physician global assessment, Visual Analog Score
|How to cite this URL:|
Shobha V, Kodishala C, Chandrashekara S, Kumar S, Haridas V, Rao V, Jois R, Daware M, Singh YP, Singhai S, Dharmanad B G, Chebbi P, Subramanian R, Kamath A, Karjiigi U, Jain VK, Dharmapalaiah C, Prasad S, Srinivas C, Ramya J, Pinto B, Nazir B, Harshini, Mahendranath. Impaired mobility drives disability in psoriatic arthritis – An observational study from Karnataka Psoriatic Arthritis Cohort (KPsAC). Indian J Rheumatol [Epub ahead of print] [cited 2023 Feb 7]. Available from: https://www.indianjrheumatol.com/preprintarticle.asp?id=353990
| Introduction|| |
Psoriatic arthritis (PsA) is a chronic inflammatory disease affecting approximately 30% of patients with skin psoriasis (PsO). The clinical manifestations are diverse including skin and nail PsO, peripheral arthritis, axial spondyloarthritis (SpA), enthesitis, and dactylitis. Symmetric polyarthritis (SP), asymmetric oligoarthritis, distal interphalangeal (DIP) joint predominant, SpA and arthritis mutilans are the five non-mutually exclusive patterns of joint involvement. Structural damage to the joints in PsA results in loss of physical function. The GRAPPA–Outcome Measures in Rheumatology PsA working group has endorsed two instruments for measurement of physical function: (1) the Health Assessment Questionnaire-Disability Index (HAQ-DI) and (2) the physical functioning domain in the Medical Outcomes Study 36-item Short-Form Survey.
Patients with PsA experience a substantial burden of physical impairment, consequent to not only joint involvement but also from enthesitis, dactylitis, axial disease, and PsO itself., Several patient-reported outcome measures (PROMs) have been used to assess the physical function in PsA., Even though these, especially PROMs, have been used in clinical trials in PsA, and several registries, most have not been developed specifically for PsA. The HAQ-DI is one of the commonly used PROMs to assess physical function. HAQ-DI was developed for use in patients with rheumatoid arthritis and is considered an arthritis-specific instrument.,, Subsequently, it has been adapted for use in PsA. There exists a knowledge gap in understanding the extent of functional disability in PsA in our country. It is well established that the disease characteristics vary in different geographic regions across the world. Therefore, we undertook the present study to understand the determinants of physical function in our cohort of PsA using the Indian version of HAQ-DI (I-HAQ) and to identify disease characteristics and outcome measures contributing to the functional limitation in PsA.
| Methods|| |
All patients of PsA participating in a multicenter, cross-sectional, noninterventional study from Karnataka PsA Cohort (KPsAC), India, were self-administered the Indian version of HAQ-DI.,,, Patients were classified as per the Classification Criteria for PsA criteria between November 2018 and July 2019 from 17 dedicated rheumatology centers across Karnataka. The Indian version of HAQ-DI has 12 items assessing various domains (nine basic and three advanced activities of daily living) such as dressing, rising, eating, walking, hygiene, reach, and grip. Subjects rate the degree of difficulty they have had in the past week on a 4-point scale, ranging from 0 (no difficulty) to 3 (unable to do). The highest scores in each category are summed and divided by the number of categories scored to yield a score from 0 to 3. Tender joint count (TJC-68), swollen joint count (SJC-66), patient global assessment (PtGA) and physician global assessment (PhGA) (measured on a Visual Analog Scale (VAS) 0–100 mm) were recorded. PsO Area and Severity Index (PASI), Disease Activity Index for PsA (DAPSA), Leeds Enthesitis Index (LEI) and dactylitis (present/absent, tender/nontender, and numerical count) were noted.,,,, Patient's perception of pain was recorded using the VAS consisting of a straight line 0–100, defining extreme limits such as “no pain at all” and “pain as bad as it could be.” Minimal disease activity (MDA-5) was calculated using PtGA, Pt pain VAS, HAQ-DI, TJC, SJC, PASI, and LEI as per recommendations., Current treatment (90 days prior) and past treatment information was recorded for all study participants. Written consent was obtained from all participating subjects and respective institutional ethical clearances were obtained (Institutional Ethics Committee, St. John's Medical College, IEC no. 10/2019 dated February 10, 2019).
I-HAQ was categorized into either a score of 0 as “no difficulty” or score >0 categorized as “some difficulty.” Continuous variables were reported as mean ± standard deviation (SD) and median with interquartile range and categorical variables as frequencies and percentages. Correlation coefficient was reported between I-HAQ value with DAPSA, VAS, PhGA, PtGA, TJC, and SJC scores. Concordance between PhGA and PtGA was done using correlation and paired t-test. Chi-square test was used to test the association between categorical variables. Unadjusted and adjusted odds ratio (OR) and 95% confidence interval (CI) were reported using univariate and multivariate logistic regression analysis. Variables with P = 0.20 in the univariate analysis were considered for multivariate analysis. P < 0.05 was considered statistically significant. All analysis was carried out using SPSS (Version 25, SPSS Inc. Chicago, USA).
| Results|| |
The KPsAC comprises 549 patients, the mean age (±SD) was 39.1 (±14) years, and 56.3% were males (M:F: 1.2:1). The median duration of articular illness was 36 months (12–92) while that of PsO was 84 months (36–144). The mean I-HAQ (SD) of this cohort was 0.31 (0.45); 42% had no disability (I-HAQ = 0) while mild-to-moderate disability (I-HAQ>0–1) was noted in 48.2% and moderate-to-severe disability (I-HAQ 1–3) in 10.3%. Those with 'some disability' (I-HAQ>0) were older (P=0.02), females (I-HAQ [F]: 0.35 [0.47], I-HAQ [M]: 0.27 [0.43], P = 0.02), had higher PASI, DAPSA (P<0.0001) and less likely to meet MDA-5 (P<0.0001 compared to those with 'no disability' (I-HAQ=0). Factors associated with “some disability” are depicted in [Table 1]. All components of DAPSA (SJC, TJC, C-reactive protein (CRP), pain VAS, and PtGA) had a significant association (P < 0.0001) with “some disability” independently. Individually, some disability on I-HAQ was maximally associated with patient pain VAS score (r = 0.568, P < 0.001) followed by PhGA (r = 0.504) and TJC and SJC (r = 0.43, 0.41), respectively. Duration of arthritis and BMI did not correlate with I-HAQ.
|Table 1: Factors associated with Health Assessment Questionnaire-Disability Index categories|
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A significantly higher proportion of patients in asymmetric oligoarthritis, DIP predominant arthritis, and arthritis mutilans subgroups had an I-HAQ of 0. It was observed that maximum disability was noted in the SP (0.34) and SpA (0.32) subgroups compared to asymmetric oligoarthritis (0.19, P = 0.0006), DIP predominant arthritis (0.12, P = 0.0001), and arthritis mutilans (0.12, P = 0.004) subgroups.
In the multivariate analysis modeling, in model 1, adjusted for age, sex, and PhGA, higher DAPSA score (OR = 1.07, 95% CI: 1.04–1.09) was more likely to be associated with “some disability” category and higher PhGA had higher odds (OR = 1.01, 95% CI: 1.001–1.02) of association. In model 2, considering age, sex, asymmetric oligoarthritis, DIP predominant, PtGA, PhGA, PASI, VAS, TJC, SJC, and CRP values, it was observed that higher PtGA (OR = 1.01, 95% CI: 1.001–1.02), higher VAS score (OR = 1.03, 95% CI: 1.01–1.04), and TJC (OR = 1.06. 95% CI: 1.01–1.09) were more likely to be associated with some disability (P < 0.001) after adjusting for other covariates.
[Table 2] describes the correlation between the individual I-HAQ questions, total I-HAQ score, and outcome measures. Correlation between each parameter of the I-HAQ questionnaire with the total I-HAQ ranged from 0.53 to 0.78. The questions which correlated highly with total I-HAQ were squatting in the toilet or sitting cross-legged on the floor (r = 0.78), walking three kilometers (r = 0.77), and climbing a flight of stairs (r = 0.74). Activity of daily living which was affected most frequently was “climbing a flight of stairs.” VAS score was maximally influenced by dress yourself (Q1), get in and get out of vehicles (Q9), and climbing up (Q12).
|Table 2: Correlation* between Health Assessment Questionnaire-Disability Index questions and outcome parameters|
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The concordance between PtGA and PhGA was assessed and a significant positive correlation (r = 0.70, P < 0.001) was noted. However, the mean PtGA was significantly higher compared to PhGA (40.77 ± 25.7 vs. 28.7 ± 24.1, P < 0.001).
About 60% (227/549) of this cohort were on continuous treatment with a rheumatologist for a minimum of 6 months. Overall, the majority were treated with disease-modifying antirheumatic drugs (DMARDs) (90.1%); methotrexate was prescribed in large majority (80.5%) either as monotherapy or in combination with other DMARDs, namely sulfasalazine (9.5%) or leflunomide (16.2%) or apremilast (10.7%). It was observed that I-HAQ was significantly lower in this group (DMARDs for 6 months or more) compared to those on lesser duration of DMARDs (0.21 [0.35], 0.38 [0.48]; P = 0.0001). Overall, those on treatment with methotrexate for >6 months were significantly associated with “no disability” on I-HAQ (P < 0.002).
| Discussion|| |
As shared decision-making is becoming a core factor in choosing therapeutic options, PROMs have become important tools to evaluate the effectiveness of therapeutic interventions., This is an observational study in a real-life setting in patients with PsA on treatment and follow-up with rheumatologists. HAQ was recorded during routine clinic visits prior to any intervention. This provided an opportunity to observe physical function in native/existing disease conditions without any expectations. However, there might be an exaggeration of HAQ in this scenario as patients frequently tend to schedule their regular visit when in pain or discomfort. I-HAQ (Indian version) which was originally modified from HAQ-DI and multidimensional health assessment questionnaire was chosen over CRD Pune HAQ due to its brevity, ease of administration, and familiarity with the questionnaire among investigators.,, CRD Pune HAQ has 23 questions in 8 domains, while HAQ-DI Indian version has 12 questions altogether. As PsA can affect many other spheres of patients' lives such as vocational and avocational activities, sleep, mood, and coping skills, EULAR has developed PsA Impact of Disease questionnaire in an attempt to capture all these aspects; however, this has not been validated for Indian context, and also, it may not be pertinent for our social setup.
Approximately half of our cohort had moderate-to-severe disability. This finding is in concordance with the disability reported in PsA cohorts from Western countries.,, Comparable to our study, Jones et al. also found that HAQ-DI was highest in the subset of PsA with SP. This is expected as this group tends to have maximum inflammatory burden in the peripheral joints. However, it is a well-recognized fact that HAQ-DI may fail to capture the disability due to axial disease in PsA. To address this, various modifications of HAQ have been proposed, but none stands entirely useful to date.
In some initial studies, HAQ-DI scores did not correlate strongly with DAPSA. However, subsequent observations have indicated that the HAQ-DI can distinguish well across different PsA disease severity. In our study, we found a strong association between I-HAQ and outcome measures, namely DAPSA, its components, MDA-5, and PhGA. However, a stand-alone analysis of inflammatory parameters such as CRP reveals that 43% had high CRP despite 0 I-HAQ while 29.6% had normal CRP value despite abnormal I-HAQ [Supplementary Figure 1].
We analyzed the influence of all questions in the I-HAQ on DAPSA and its individual components. PtGA, VAS, and TJC had a maximal impact on I-HAQ. Pain seems to be the primary driver of HAQ but surely not the only one; structural damage is a well-known promoter of physical disability in PsA. We observed that I-HAQ parameters which contribute to maximum disability in KPsAC were related to mobility or pertaining to questions related to lower-limb joints. The I-HAQ was designed to include our country/region-specific activities such as squatting in the toilet or sitting cross-legged on the floor which were not included in HAQ-DI. Our analysis also informs that these two activities along walking three kilometers and climbing a flight of stairs had a major impact on I-HAQ. This is in relative contrast to prior publications wherein HAQ-DI was driven by components related to dressing and grooming and to eating abilities.
As MDA-5 is a multidimensional tool, covering several domains of PsA including skin disease, HAQ-DI, patient pain VAS, and PtGA disease activity VAS, expectedly there is a good correlation between overall I-HAQ and MDA-5. There is an ongoing debate whether measures of inflammation and function/damage should be included in the same composite score such as MDA-5, as these represent different constructs. I-HAQ was lower in those who have been on methotrexate-based treatment for 6 months or more in our cohort. The proportion of patients on continuous biologic treatment was very small; therefore, this aspect could not be analyzed.
We also compared PtGA and PhGA of disease activity. Concordance between patients' and physicians' ratings of general health status was good; however, the mean PtGA score was significantly higher compared to PhGA score.,,, Even though the discordant viewpoint is minor, this suggests that there are pertinent factors which are not interpreted by physicians while they continue to hamper routine daily life for patients.
The HAQ-DI has several limitations for use in PsA, such as clustering toward lower values or floor effect, underestimation of physical impairment in those with predominant skin disease, and lack of responsiveness to treatment effects, especially in the late disease. In our study as well, we found floor effect, almost half of our cohort had a I-HAQ score of 0. In univariate analysis, PASI had a significant influence on I-HAQ, but this effect was lost in multivariate analysis. Additional health-related quality-of-life instruments, such as the Dermatology Life Quality Index, may need to be used in parallel to obtain a more complete picture of the disease burden. Furthermore, there are no PsA-specific instruments to assess physical function and health-related quality-of-life questionnaires validated in India.
Complete evaluation of the patients with a wide number of validated outcome instruments and the expertise of investigators in a real-life setting are major strengths of our study. Some of our limitations were that we used the English version of I-HAQ which resulted in restricting the participants, and we also performed a single-time-point evaluation which has to be considered while interpreting the results. The compliance to treatment was not evaluated using a structured format.
| Conclusions|| |
As we move toward patient-centered care, understanding gaps in delivery of care bears immense importance. Through our study, we report that the I-HAQ appears to be a valuable assessment tool that clinicians should use in clinical practice in PsA patients. It correlates with DAPSA and MDA-5 and subcomponents of DAPSA in our cohort. The I-HAQ was maximally influenced by patient pain VAS followed by PhGA, TJC, and SJC. Among the 12 questions included in HAQ-DI Indian version, the questions pertaining to lower-limb function maximally influenced the overall score.
We thank Ms. Sumithra Selvam, Department of Biostatistics, St. John's Research Institute for statistical support.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2]