Direct and indirect costs of idiopathic inflammatory myopathies in adults: A systematic review.

Idiopathic inflammatory myopathies (IIMs) are rare disorders characterized by inflammation of skeletal muscle, which can result in fatty replacement of muscle, muscle atrophy, and subsequent weakness. Therapeutic advancements have improved clinical outcomes but impose an economic impact on healthcare systems. We aimed to summarize the direct and indirect costs associated with IIMs in a systematic review (PROSPERO Registration #CRD42023443143). Electronic databases (MEDLINE, Embase, CINAHL, and Scopus) were systematically searched for full-length articles (excluding case reports) reporting costs specific to patients diagnosed with an IIM, published between database inception and April 19, 2023. Direct cost categories included inpatient, outpatient, medication, home/long-term care, and durable medical equipment such as mobility and respiratory aids. Indirect costs included lost productivity. Eligibility criteria were met by 21 of the 3,193 unique titles identified. Costs are expressed in 2023 United States of America dollars, with adjustments for differences in purchasing power applied to currency conversions. As no study reported on all cost categories, annualized cost of IIM per patient was estimated by calculating the mean cost per category, and then adding the means of the different cost categories. By this method, IIM was estimated to cost $52,210 per patient per year. Proportional contributions by category were lost productivity (0.278), outpatient care (0.214), medications (0.171), inpatient care (0.161), home/long-term care (0.122), and durable medical equipment (0.053). Newer findings with intravenous immunoglobulin considered first line therapy for IIM demonstrated markedly higher annual medication costs per patient, upwards of $33,900 compared to an average of $3,908 ± $1,042 in older studies. Future cost-effectiveness studies require updated cost-of-illness studies reflecting the evolving sub-classification and treatment options for IIM, and should consider the impact of IIM on patients and their families.

Real-world implications of IMACS malignancy screening guidelines for idiopathic inflammatory myopathies: An evaluation of compliance and economic impact at a tertiary referral center.

AIM: An inaugural set of consensus guidelines for malignancy screening in idiopathic inflammatory myopathy (IIM) were recently published by an international working group. These guidelines propose different investigation strategies based on "high", "intermediate" or "standard" malignancy risk groups. This study compares current malignancy screening practices at an Australian tertiary referral center with the recommendations outlined in these guidelines. METHODS: We conducted a retrospective analysis of newly diagnosed IIM patients. Relevant demographic and clinical data regarding malignancy screening were recorded. Existing practice was compared with the guidelines using descriptive statistics; costs were calculated using the Australian Medicare Benefit Schedule. RESULTS: Of the 47 patients identified (66% female, median age: 63 years [IQR: 55.5-70], median disease duration: 4 years [IQR: 3-6]), only one had a screening-detected malignancy. Twenty patients (43%) were at high risk, while 20 (43%) were at intermediate risk; the remaining seven (15%) had IBM, for which the proposed guidelines do not recommend screening. Only three (6%) patients underwent screening fully compatible with International Myositis Assessment and Clinical Studies recommendations. The majority (N = 39, 83%) were under-screened; the remaining five (11%) overscreened patients had IBM. The main reason for guideline non-compliance was the lack of repeated annual screening in the 3 years post-diagnosis for high-risk individuals (0% compliance). The mean cost of screening was substantially lower than those projected by following the guidelines ($481.52 [SD 423.53] vs $1341 [SD 935.67] per patient), with the highest disparity observed in high-risk female patients ($2314.29/patient). CONCLUSION: Implementation of the proposed guidelines will significantly impact clinical practice and result in a potentially substantial additional economic burden.

Diagnosing and characterizing inflammatory myopathies at an Australian tertiary public hospital: Resource utilization and direct healthcare costs.

AIM: To determine the direct health service costs and resource utilization associated with diagnosing and characterizing idiopathic inflammatory myopathies (IIMs), and to assess for limitations and diagnostic delay in current practice. METHODS: A retrospective, single-center cohort analysis of all patients diagnosed with IIMs between January 2012 and December 2021 in a large tertiary public hospital was conducted. Demographics, resource utilization and costs associated with diagnosing IIM and characterizing disease manifestations were identified using the hospital's electronic medical record and Health Intelligence Unit, and the Medicare Benefits Schedule. RESULTS: Thirty-eight IIM patients were identified. IIM subtypes included dermatomyositis (34.2%), inclusion body myositis (18.4%), immune-mediated necrotizing myopathy (18.4%), polymyositis (15.8%), and anti-synthetase syndrome (13.2%). The median time from symptom onset to diagnosis was 212 days (IQR: 118-722), while the median time from hospital presentation to diagnosis was 30 days (8-120). Seventy-six percent of patients required emergent hospitalization during their diagnosis, with a median length of stay of 8 days (4-15). The average total cost of diagnosing IIM was $15 618 AUD (STD: 11331) per patient. Fifty percent of patients underwent both MRI and EMG to identify affected muscles, 10% underwent both pan-CT and PET-CT for malignancy detection, and 5% underwent both open surgical and percutaneous muscle biopsies. Autoimmune serology was unnecessarily repeated in 37% of patients. CONCLUSION: The diagnosis of IIMs requires substantial and costly resource use; however, our study has identified potential limitations in current practice and highlighted the need for streamlined diagnostic algorithms to improve patient outcomes and reduce healthcare-related economic burden.

Medical costs and health-care resource use in patients with inflammatory myopathies in an insured population.

INTRODUCTION: In this study we determined the health-care costs and resource utilization associated with idiopathic inflammatory myopathies (IIMs) in a large managed care plan in the USA. METHODS: Myositis subjects ≥18 years of age with claims-based evidence of IIMs were identified from a health plan database. Subjects were matched with unaffected controls, and costs and resource use were determined during a 12-month period. RESULTS: A total of 1781 newly diagnosed IIM subjects were matched to 5343 controls, and 2697 subjects with existing disease were matched to 8091 controls. Mean overall annual medical costs were higher among newly diagnosed subjects ($16,319 vs. $4926, P < 0.001) and subjects with an existing IIM ($15,539 vs. $5210, P < 0.001) in comparison to controls. IIM subjects had significantly higher mean counts of ambulatory visits, specialist visits, and inpatient hospital stays compared with controls (all P < 0.001). CONCLUSION: Our analysis suggests that IIMs have increased medical costs and resource use.

Healthcare costs of inflammatory myopathies.

OBJECTIVE: Little information exists regarding the economic burden related to inflammatory myopathies. Our objective was to estimate health services costs in a large, unselected, population-based sample of patients with inflammatory myopathies. METHODS: We identified subjects with polymyositis and dermatomyositis from administrative healthcare databases (covering all beneficiaries, about 7.5 million) in Quebec province, Canada. Average estimates of health services costs (physician visits, diagnostic tests and procedures, outpatient surgeries and procedures, acute care hospitalizations) for 2003 were calculated by multiplying health service use levels by the appropriate unit prices, determined from government fee schedules and other sources. Multiple linear regression analyses were performed to establish whether specific factors (age, sex, disease duration, region of residence, socioeconomic status, type of myositis, disease severity) were associated with cost. RESULTS: We identified 1102 subjects with inflammatory myopathy from January 1, 1989, to January 1, 2003. About two-thirds were women (68.9%); average age at case ascertainment was 57.4 years (SD 18.4). The average cost of all reimbursed health services, in 2008 Canadian dollars, was $4099 per patient (SD $9639). Costs increased with age, and were highest early in the disease course. Greater disease severity (defined as the need for prior hospitalization for myositis) was also a strong predictor of both physician costs and total costs. CONCLUSION: These results indicate significant economic burden related to inflammatory myopathies, with important demographic predictors. Our estimates suggest that the health services costs in inflammatory myopathies may equal, or exceed, those of other serious diseases, such as rheumatoid arthritis and systemic sclerosis.