Work ability in patients with polymyositis and dermatomyositis: An explorative and descriptive study

Epidemiology of the idiopathic inflammatory myopathies

The idiopathic inflammatory myopathies (IIMs) are a heterogeneous group of systemic autoimmune diseases that affect the skeletal muscles and can also involve the skin, joints, lungs and heart. The epidemiology of IIM is obscured by changing classification criteria and the inherent shortcomings of case identification using healthcare record diagnostic coding. The incidence of IIM is estimated to range from 0.2 to 2 per 100,000 person-years, with prevalence from 2 to 25 per 100,000 people. Although the effects of age and gender on incidence are known, there is only sparse understanding of ethnic differences, particularly in indigenous populations. The incidence of IIM has reportedly increased in the twenty-first century, but whether this is a genuine increase is not yet known. Understanding of the genetic risk factors for different IIM subtypes has advanced considerably. Infections, medications, malignancy and geography are also commonly identified risk factors. Potentially, the COVID-19 pandemic has altered IIM incidence, although evidence of this occurrence is limited to case reports and small case series. Consideration of the current understanding of the epidemiology of IIM can highlight important areas of interest for future research into these rare diseases.

Work situation, work ability and expectation of returning to work in patients with systemic autoimmune myopathies

OBJECTIVES

To document the work situation, the work ability and the expectation of returning to work among adult patients with systemic autoimmune myopathies (SAMs), and to identify the factors associated with each of these outcomes.

METHODS

Cross-sectional study. The work situation (performing paid work vs out of work) was ascertained via a structured questionnaire. For those who were working, we applied the Work Ability Index (WAI; scale 7-49); and for those who were out of work, we applied the Return-to-Work Self-Efficacy questionnaire (RTW-SE; scale 11-66).

RESULTS

Of the 75 patients with SAMs included, 33 (44%) were doing paid work and 42 (56%) were out of work. The work situation was independently associated with physical function, assessed by the Health Assessment Questionnaire-Disability Index (HAQ-DI). A 1-point increase in the HAQ-DI (scale 0-3) decreased the chance of doing paid work by 66% (95% CI: 0.16, 0.74; P = 0.007). Patients performing paid work had a mean WAI of 33.5 (6.9). The following variables were associated with a decrease in the WAI score in the regression model: female sex (-5.04), diabetes (-5.94), fibromyalgia (-6.40), fatigue (-4.51) and severe anxiety (-4.59). Among those out of work, the mean RTW-SE was 42.8 (12.4). Cutaneous manifestations and >12 years of education were associated with an average increase of 10.57 and 10.9 points, respectively, in the RTW-SE. A 1-point increase in the HAQ-DI decreased the RTW-SE by 4.69 points.

CONCLUSION

Our findings highlight the poor work participation in a well-characterized sample of working-age patients with SAMs. Strategies to improve work-related outcomes in these patients are urgently needed.

Distribution and trajectory of direct and indirect costs of idiopathic inflammatory myopathies

OBJECTIVES

To estimate the annual direct and indirect costs associated with Idiopathic Inflammatory Myopathies (IIM) over time, including the pre-diagnostic period.

METHODS

A cohort of incident adult IIM patients (n = 673) was identified from the Swedish National Patient Register from 2010 to 2016 and matched with general population comparators (n = 3343). Follow-up started at IIM diagnosis and corresponding date in the general population. International Classification of Diseases codes (ICD-10) were used for IIM case definition. Costs were calculated using national register data.

RESULTS

The costs related to IIM started to increase 2 years before diagnosis. In the year following diagnosis, the mean annual IIM cost was €21 639 compared to €4816 in the general population. Five years after diagnosis, the mean annual cost in the IIM cohort was €12 796. Outpatient visits, hospitalizations and productivity loss were the components driving the increment in overall annual disease-related expenditures. Indirect costs accounted for a significant portion of IIM long-term societal costs. The highest costs were found in individuals of working age with cancer-associated IIM.

CONCLUSIONS

The mean annual costs in IIM were 3 to 5 times higher than in the general population in the 5-year period following diagnosis. These costs started to increase long before diagnosis, were at their peak in the year post-diagnosis and remained elevated thereafter. Indirect costs contributed to a substantial portion of this increment. Early in the IIM disease course, clinicians and allied health professionals should aim to improve function, reduce damage and address barriers to return-to-work to mitigate these costs.

Costs of Workplace Productivity Loss in Patients with Connective Tissue Disease-associated Interstitial Lung Disease

Rationale: Interstitial lung disease (ILD) develops in a large percentage of patients with connective tissue disease (CTD) and is associated with increased morbidity and mortality. Patients with CTD-associated ILD (CTD-ILD) often present at a young age, suggesting that ILD likely impacts workplace productivity.Objectives: We aimed to determine the employment rate and workplace productivity loss, along with its associated factors and estimated costs, in patients with fibrotic CTD-ILD.Methods: Patients with fibrotic CTD-ILD from the six centers of the Canadian Registry for Pulmonary Fibrosis were eligible. Health-related productivity loss was assessed using the Work Productivity and Activity Impairment questionnaire. Proposed factors associated with low workplace productivity were forced into a multivariable regression model. Average productivity loss in hours/week was used to calculate the costs of productivity loss based on hourly wages obtained from national census data matched for age and sex. Workplace productivity loss outcomes were compared between patients with CTD-ILD and patients with a non-CTD fibrotic ILD.Results: Of 375 eligible patients with fibrotic CTD-ILD, 113 (30%) were employed. Productivity loss was reported by 59% of employed patients, with a mean loss of 9.4 ± 1.2 hours/week, including 3.9 ± 0.9 hours/week from absenteeism and 5.5 ± 0.7 hours/week from presenteeism. Employment among patients 25-54 years of age with fibrotic CTD-ILD was 27% lower than that in the matched general Canadian population (56% vs. 83%; P < 0.001). Employment among patients ≥55 years of age with CTD-ILD was 17% lower than that in the matched population (19% vs. 36%; P < 0.001). Workplace productivity loss was not associated with respiratory symptoms or lung physiology. Annual costs of productivity loss were calculated at 13,593 Canadian dollars per employee with fibrotic CTD-ILD. Workplace productivity loss was similar in patients with fibrotic CTD-ILD and those with non-CTD fibrotic ILD.Conclusions: Patients with fibrotic CTD-ILD frequently report workplace productivity loss, which is unexplained by respiratory symptoms or lung physiology and is associated with significant costs.

The effect of a 24-week training focused on activities of daily living, muscle strengthening, and stability in idiopathic inflammatory myopathies: a monocentric controlled study with follow-up

BACKGROUND

The structural and functional changes of the skeletal muscles in idiopathic inflammatory myopathies (IIM) caused by inflammation and immune changes can be severely disabling. The objective of this study was to assess the effect of a 24-week program combining a supervised training of activities of daily living (ADL), resistance, and stability with home exercise for improving muscle function, compared to a daily home-based exercise representing the regular outpatient care.

METHODS

Fifty-seven patients with IIM were consecutively and non-selectively enrolled in an intervention (IG, n = 30) or control (CG, n = 27) group. Both groups were provided a standard-of-care pharmacological treatment and follow-up. Only the IG underwent the supervised intervention twice a week for 1 h per session. At baseline, 12, 24, and 48 weeks, all patients were assessed by an assessor blinded to the intervention for primary outcomes: muscle strength (Manual Muscle Testing of eight muscle groups [MMT-8]) and endurance (Functional Index-2 [FI-2]), and secondary outcomes: stability and body composition. Secondary outcomes also included questionnaires evaluating disability (Health Assessment Questionnaire [HAQ]), quality of life (Short Form 36 [SF-36]), depression (Beck's Depression Inventory-II [BDI-II]), and fatigue (Fatigue Impact Scale [FIS]), and analysis of the systemic and local inflammatory response and perceived exertion to assess the safety of the intervention.

RESULTS

Twenty-seven patients in the IG and 23 in the CG completed the entire program and follow-up. At week 24, compared to deterioration in the CG, we found a significant improvement in the IG in muscle strength (mean % improvement compared to baseline by 26%), endurance (135%), disability (39%), depression (26%), stability (11%), and basal metabolism (2%) and a stabilization of fitness for physical exercise. The improvement was clinically meaningful (a 24-week change by >20%) in most outcomes in a substantial proportion of patients. Although the improvement was still present at 48 weeks, the effect was not sustained during follow-up. No significant increase in the systemic or local expression of inflammatory markers was found throughout the intervention.

CONCLUSIONS

This 24-week supervised intervention focused on ADL training proved to be safe and effective. It not only prevented the progressive deterioration, but also resulted in a significant improvement in muscle strength, endurance, stability, and disability, which was clinically meaningful in a substantial proportion of patients.

TRIAL REGISTRATION

ISRCTN35925199 (retrospectively registered on 22 May 2020).

Health-related quality of life and work impairment in idiopathic inflammatory myopathies in South Australia

AIM

The idiopathic inflammatory myopathies (IIM) are rare autoimmune diseases that are usually chronic and often present with skeletal muscle inflammation and weakness. We sought to examine the impact of IIM in a cohort of 50 South Australian patients on health-related quality of life (HRQOL) and work productivity (WP). We uniquely categorized patients across gender, IIM subtypes, employment status, and also whether there was extramuscular involvement from IIM.

METHODS

Multiple modalities were used, as recommended by the International Myositis Assessment and Clinical Studies Group (IMACS), to assess the impact of IIM, including manual muscle strength testing (MMT-8), the Physician and Patient Global Activity Assessments (PHGAA, PTGAA), Myositis Disease Activity Assessment Tool (MDAAT), and serum creatinine kinase (CK) levels. The impacts of IIM on HRQOL and WP were analyzed using the Medical Outcomes Study 36-items Short Form (SF-36) and Work Productivity and Activity Impairment (WPAI) questionnaires, respectively.

RESULTS

We found significantly lower HRQOL outcome scores in most of the SF-36 domains when compared to the most recent population norms (P ≤ .01). Physical health was predominantly affected with relative preservation of emotional health. There were also significant associations between MMT-8, PHGAA and PTGAA scores and HRQOL and WP.

CONCLUSIONS

Our findings highlight the significant impact of IIM on HRQOL and WP in a well-characterized cohort of patients with IIM within Australia, and therefore the importance of a holistic approach to the management of these patients.

Patient-reported dermatomyositis and polymyositis flare symptoms are associated with disability, productivity loss, and health care resource use

BACKGROUND: Flare activity or worsening symptoms are not well defined for myositis. OBJECTIVES: To (a) characterize dermatomyositis (DM) and polymyositis (PM) flares from the patient perspective and (b) report the corresponding disability and rate of unplanned medical encounters. METHODS: Online survey data were collected from volunteer patients from The Myositis Association and Johns Hopkins Myositis Center. Flare frequency; Health Assessment Questionnaire Disability Index (HAQ-DI), HAQ-Pain Index, Work Productivity and Activity Impairment (WPAI) scales; emergency department/urgent care (ED/UC) visits; and hospital admissions during the past year were examined. RESULTS: 564 individuals with selfreported diagnoses of DM/PM were surveyed between December 2017 and May 2018. Recall of symptom flares was reported by 524 respondents (78.1% were female, mean age of 55 years). Among the respondents, 378 (72.1%) reported ≥ 1 flare in the past year. The pattern of flare frequency was similar for DM and PM respondents. The most common symptoms were muscle weakness (83%), extreme fatigue (78%), and muscle pain/discomfort (64%). Increasing flare frequency was associated with significantly (P < 0.01) greater mean HAQ-DI and HAQ-Pain scores, myositis-related ED/UC visits, hospital admissions, WPAI work productivity loss (among those employed), and WPAI nonwork activity impairment. CONCLUSIONS: DM/PM-related flares are common with exacerbations of muscle weakness and fatigue being the most common flare symptoms. Flare frequency was associated with greater disability, pain, work productivity loss, nonwork activity impairment, and increased ED/UC utilization. Higher frequency of patient-reported flares may serve as a marker of worsening physical functioning and intensifying health care needs and, therefore, suggests their importance in the clinical assessment of patients with DM/PM. DISCLOSURES: This study was supported by Mallinckrodt Pharmaceuticals (Bedminster, NJ) via grants to Vedanta Research and The Myositis Association. Christopher-Stine has received compensation from previous Mallinckrodt Advisory Board meetings, unrelated to this subject matter. Wan is an employee of Mallinckrodt Pharmaceuticals and is a stockholder of the company. Reed and Bostic received grant support from Mallinckrodt Pharmaceuticals for data collection and analysis. McGowan is an employee of The Myositis Foundation, which received grant funding to support study data collection. Kelly has no conflicts to disclose. This study was presented, in part or full, at the 2019 Annual American College of Rheumatology and Association of Rheumatology Professional Meeting (November 8-13, 2018; Atlanta, GA) and at the Third Global Conference on Myositis (March 27, 2019; Berlin, Germany).

Productivity Losses and Costs in the Less-Common Systemic Autoimmune Rheumatic Diseases

PURPOSE OF REVIEW

We synthesised the literature on productivity losses and costs in the less-common systemic autoimmune rheumatic diseases: Sjogren's syndrome (SjS), systemic sclerosis (SSc), poly/dermatomyositis (PM/DM), and systemic vasculitides (SV).

RECENT FINDINGS

Of 29 studies located, 12 were published 2012 onwards (SSc = 6, SjS = 2, PM/DM = 2, SV = 2). In these, 25% of PM/DM, and 21-26% of SV, were work disabled, 22% of SSc stopped work within 3 years of diagnosis, and annual costs of absenteeism in SSc averaged $12,024 2017 USD. Very few studies reported on costs, presenteeism (working at reduced levels), or unpaid productivity loss. Across multiple systemic autoimmune rheumatic diseases (SARDs), major drivers of lost productivity were generalised items like pain, depression, and fatigue, rather than disease-specific factors. Evidence suggests that work disability is common in SSc and strikes quickly. However, in SSc and other SARDs, more comprehensive estimates are needed, which include absenteeism and presenteeism from paid and unpaid work, costs, and drivers of productivity loss.