True difference or something else? Problems in cost of osteoarthritis studies

Distribution and Drivers of Average Direct Cost of Osteoarthritis in Canada From 2003 to 2010

OBJECTIVE

To estimate the distribution and drivers of the average direct cost of osteoarthritis (OA) in Canada using a population-based health microsimulation model of OA from 2003 to 2010.

METHODS

We used a previously published microsimulation model to estimate the distribution of average cost of OA across different cost components and OA stages. OA stages were defined according to the patient flow within the health care system. Cost components associated with pharmacologic and nonpharmacologic treatments, physician visits, and hospitalization were included. Scenario analysis was performed to evaluate average cost drivers from 2003 to 2010.

RESULTS

During the study period, the OA population size grew from 2.9 to 3.6 million, while the average cost increased from $577 to $811 (Canadian) per patient per year. The highest increase in share of cost components was for total joint replacement (TJR) surgery (24% to 32%). The highest average cost was incurred by patients in stage 4 (during and after revision surgery), while around 80% of OA patients were in stage 1 (OA diagnosed but has not visited an orthopedic surgeon). Increase in the proportion of OA patients receiving TJR surgeries (34%) and price inflation (29%) were the most significant drivers of average cost.

CONCLUSION

The average cost of OA has been increasing during the study period mostly due to an increase in the proportion of patients receiving TJR surgeries and price inflation. The distribution of average cost of OA across disease stages needs to be considered when designing policies targeting specific aspects of OA care.

Economic and Humanistic Burden of Osteoarthritis: A Systematic Review of Large Sample Studies

BACKGROUND

Osteoarthritis (OA) consumes a significant amount of healthcare resources, and impairs the health-related quality of life (HRQoL) of patients. Previous reviews have consistently found substantial variations in the costs of OA across studies and countries. The comparability between studies was poor and limited the detection of the true differences between these studies.

OBJECTIVE

To review large sample studies on measuring the economic and/or humanistic burden of OA published since May 2006.

METHODS

We searched MEDLINE and EMBASE databases using comprehensive search strategies to identify studies reporting economic burden and HRQoL of OA. We included large sample studies if they had a sample size ≥1000 and measured the cost and/or HRQoL of OA. Reviewers worked independently and in duplicate, performing a cross-check between groups to verify agreement. Within- and between-group consolidation was performed to resolve discrepancies, with outstanding discrepancies being resolved by an arbitrator. The Kappa statistic was reported to assess the agreement between the reviewers. All costs were adjusted in their original currency to year 2015 using published inflation rates for the country where the study was conducted, and then converted to 2015 US dollars.

RESULTS

A total of 651 articles were screened by title and abstract, 94 were reviewed in full text, and 28 were included in the final review. The Kappa value was 0.794. Twenty studies reported direct costs and nine reported indirect costs. The total annual average direct costs varied from US$1442 to US$21,335, both in USA. The annual average indirect costs ranged from US$238 to US$29,935. Twelve studies measured HRQoL using various instruments. The Short Form 12 version 2 scores ranged from 35.0 to 51.3 for the physical component, and from 43.5 to 55.0 for the mental component. Health utilities varied from 0.30 for severe OA to 0.77 for mild OA.

CONCLUSION

Per-patient OA costs are considerable and a patient's quality of life remains poor. Variations in costing methods are a barrier to understanding the true differences in the costs of OA between studies. Standardizing healthcare resource items, the definition of OA-relevant costs, and productivity loss measures would facilitate the comparison.

Projecting the direct cost burden of osteoarthritis in Canada using a microsimulation model

OBJECTIVES

To estimate the future direct cost of OA in Canada using a population-based health microsimulation model of osteoarthritis (POHEM-OA).

METHODS

We used administrative health data from the province of British Columbia (BC), Canada, a survey of a random sample of BC residents diagnosed with OA (Ministry of Health of BC data), Canadian Institute of Health Information (CIHI) cost data and literature estimates to populate a microsimulation model. Cost components associated with pharmacological and non-pharmacological treatments, total joint replacement (TJR) surgery, as well as use of hospital resources and management of complications arising from the treatment of osteoarthritis (OA) were included. Future costs were then simulated using the POHEM-OA model to construct profiles for each adult Canadian.

RESULTS

From 2010 to 2031, as the prevalence of OA is projected to increase from 13.8% to 18.6%, the total direct cost of OA is projected to increase from $2.9 billion to $7.6 billion, an almost 2.6-fold increase (in 2010 $CAD). From the highest to the lowest, the cost components that will constitute the total direct cost of OA in 2031 are hospitalization cost ($2.9 billion), outpatient services ($1.2 billion), alternative care and out-of-pocket cost categories ($1.2 billion), drugs ($1 billion), rehabilitation ($0.7 billion) and side-effect of drugs ($0.6 billion).

CONCLUSIONS

Projecting the future trends in the cost of OA enables policy makers to anticipate the significant shifts in its distribution of burden in the future.

How much do rheumatologists and orthopaedists doctors' modalities impact the cost of arthritis in Cyprus?

BACKGROUND

Osteoarthritis is one of the primary causes of long-term functional disability. With an estimated 13.5% prevalence in the general population contributes to a significant financial burden both for patients and healthcare systems. The purpose of this research is to highlight the direct annual cost of the disease to the private healthcare sector of Nicosia.

METHODS

A questionnaire based on Greek and international research was completed between 10/1/2012 and 11/30/2012, with a sample of 20 doctors specialists in orthopaedics and rheumatology (50% of practising physicians in the private sector). An assessment of the annual cost of medical procedures and tests, pharmacologic therapies (modalities) and supplies per patient followed, based on current costs. Direct costs were assessed through the micro-costing "bottom-up" approach. We isolated and separately priced the original diagnosis, followed by each stage of the disease.

RESULTS

The cost for the six predominant medical tests to establish a diagnosis and exclude mainly RA such as ESR, CPR, and X-ray as well as a physician's office visit was 150€ per patient. The average direct cost per patient during stages 1, 2 and 3 of the disease was 280.54€, 1,834.64€ and 5,641.72€ annually, respectively, with an annual average of 2,573€ per patient.

CONCLUSIONS

Even though during the period of the study, the country had not yet established clinical guidelines, the participating physicians followed international practices. Significant rise in the cost in each stage of the disease was found, with additional increases in the following years as a result of the expected increased prevalence of the disease. It is noted here that uninsured patients, as well as those who qualified for free medical care, they seek these services in the private sector, and had to pay out of pocket money for examination and treatment. These patients, thus, contended with a serious financial burden. Therefore, it is important to inform them very extensively regarding evidence-based management of the disease to aid them in coping with this chronic illness.

Lifetime medical costs of knee osteoarthritis management in the United States: impact of extending indications for total knee arthroplasty

OBJECTIVE

The impact of increasing utilization of total knee arthroplasty (TKA) on lifetime costs in persons with knee osteoarthritis (OA) is understudied.

METHODS

We used the Osteoarthritis Policy Model to estimate total lifetime costs and TKA utilization under a range of TKA eligibility criteria among US persons with symptomatic knee OA. Current TKA utilization was estimated from the Multicenter Osteoarthritis Study and calibrated to Health Care Cost and Utilization Project data. OA treatment efficacy and toxicity were drawn from published literature. Costs in 2013 dollars were derived from Medicare reimbursement schedules and Red Book Online. Time costs were derived from published literature and the US Bureau of Labor Statistics.

RESULTS

Estimated average discounted (3% per year) lifetime costs for persons diagnosed with knee OA were $140,300. Direct medical costs were $129,600, with $12,400 (10%) attributable to knee OA over 28 years. OA patients spent a mean ± SD of 13 ± 10 years waiting for TKA after failing nonsurgical regimens. Under current TKA eligibility criteria, 54% of knee OA patients underwent TKA over their lifetimes. Estimated OA-related discounted lifetime direct medical costs ranged from $12,400 (54% TKA uptake) when TKA eligibility was limited to Kellgren/Lawrence grades 3 or 4 to $16,000 (70% TKA uptake) when eligibility was expanded to include symptomatic OA with a lesser degree of structural damage.

CONCLUSION

Because of low efficacy of nonsurgical regimens, knee OA treatment-attributable costs are low, representing a small portion of all costs for OA patients. Expanding TKA eligibility increases OA-related costs substantially for the population, underscoring the need for more effective nonoperative therapies.

Socio-economic costs of osteoarthritis: a systematic review of cost-of-illness studies

OBJECTIVE

The burden of illness that can be attributed to osteoarthritis is considerable and ever increasing. The aim of this systematic review is to analyze currently available data derived from cost-of-illness studies on the healthcare and non-healthcare costs of osteoarthritis.

METHODS

PubMed, Index Medicus Español (IME), and the Spanish Database of Health Sciences [Índice Bibliográfico Español en Ciencias de la Salud (IBECS)] were searched up to the end of April 2013. This study adhered to the PRISMA guidelines. Articles were reviewed and the study quality assessed by two independent investigators with consensus resolution of discrepancies.

RESULTS

We identified 39 studies that investigated the socio-economic cost of osteoarthritis. Only nine studies took a social perspective. Rather than estimating the incremental cost of osteoarthritis, nine studies estimated the total cost of treating patients with osteoarthritis without a control for comorbidity. The other 30 studies determined the incremental cost with or without a control group. Only nine studies assessed a comprehensive list of healthcare resources. The annual incremental healthcare costs of generalized osteoarthritis ranged from €705 to €19,715. The annual incremental non-healthcare-related costs of generalized osteoarthritis ranged from €432 to €11,956.

CONCLUSIONS

The study concludes that the social cost of osteoarthritis could be between 0.25% and 0.50% of a country׳s GDP. This should be considered in order to foster studies that take into account both healthcare and non-healthcare costs.

Transferability of indirect cost of chronic disease: a systematic review and meta-analysis

BACKGROUND

Indirect cost is an important component in economic evaluations. The variation in the magnitude of indirect costs across studies and countries is substantial and affects the transferability of results across jurisdictions.

OBJECTIVE

This study explored the factors involved in the variation of reported indirect cost and investigated the feasibility of transferring indirect costs across settings.

METHODS

A systematic literature review was conducted to identify studies estimating indirect costs for four selected chronic diseases, namely, asthma (AS), diabetes (DI), rheumatoid arthritis (RA) and schizophrenia (SC). A multiple linear regression analysis was run to identify the factors that potentially explain the variation in reported indirect costs. Parametric (fixed- and random-effect models) and non-parametric (bootstrapping method) meta-analyses were applied to local gross domestic product (GDP)/capita-adjusted indirect costs for each disease. Results from the three different analytical methods were compared to ascertain the robustness of estimation.

RESULTS

The systematic literature review identified 77 articles that reported indirect costs of AS (n = 18), DI (n = 20), RA (n = 25) and SC (n = 14) for literature synthesis. Substantial inter- and intra-disease variations among the indirect cost studies were observed with respect to geographic distribution, methodology and magnitude of cost estimation. Regression analysis showed that disease categories and local GDP/capita significantly (p < 0.001) contributed to the variance of indirect cost. The range of intra-disease variation in indirect costs was substantially reduced after adjusting by and expressing values as local GDP/capita. The GDP-adjusted indirect cost in terms of percentage of local GDP/capita of AS was the lowest and that of SC was the highest. Bootstrapping estimation was relatively conservative, with slightly wider confidence intervals (CIs) than the parametric method, with a mean (95 % CI) of 2.12 % (1.4089-2.9332) for AS, 10.65 % (7.215-14.7438) for DI, 21.98 % (17.4360-27.0631) for RA, and 79.19 % (52.4243-117.833) for SC.

CONCLUSION

It would be convenient and feasible to construct a universal reference range of indirect cost for a specific disease based on existing data and present this as a percentage of local GDP to assist local decision making in jurisdictions where indirect cost data are not available.

Cost of rheumatic disorders in the Netherlands

Rheumatic disorders concern a broad spectrum of painful disorders affecting the musculoskeletal system, and are responsible for a considerable amount of disease burden and also a substantial economic burden. This economic burden consists of direct and indirect costs, but also the so-called intangible costs. In this study, we estimated the societal cost of rheumatic disorders in the Netherlands, including intangible costs. Data from the National Monitor on Musculoskeletal System 2010 were used to assess resource used, multiplied with standard prices for the Netherlands to obtain total costs for the 1.8 million people suffering from rheumatic disorders. These estimates were supplemented with data from secondary sources. Total societal costs of rheumatic disorders in the Netherlands amount to €4.7 million a year, that is, €2665 per person with rheumatic disorders. Rheumatic disorders have considerable costs, which justify more attention in discussing investments in facing the challenges in our ageing Western societies.

The Global Economic Cost of Osteoarthritis: How the UK Compares

Aims. To examine all relevant literature on the economic costs of osteoarthritis in the UK, and to compare such costs globally. Methods. A search of MEDLINE was performed. The search was expanded beyond peer-reviewed journals into publications by the department of health, national orthopaedic associations, national authorities and registries, and arthritis charities. Results. No UK studies were identified in the literature search. 3 European, 6 North American, and 2 Asian studies were reviewed. Significant variation in direct and indirect costs were seen in these studies. Costs for topical and oral NSAIDs were estimated to be £19.2 million and £25.65 million, respectively. Cost of hip and knee replacements was estimated to exceed £850 million, arthroscopic surgery for osteoarthritis was estimated to be £1.34 million. Indirect costs from OA caused a loss of economic production over £3.2 billion, £43 million was spent on community services and £215 million on social services for osteoarthritis. Conclusions. While estimates of economic costs can be made using information from non-published data, there remains a lack of original research looking at the direct or indirect costs of osteoarthritis in the UK. Differing methodology in calculating costs from overseas studies makes direct comparison with the UK difficult.

Magnetic resonance imaging of ferumoxide-labeled mesenchymal stem cells in cartilage defects: in vitro and in vivo investigations

The purpose of this study was to (1) compare three different techniques for ferumoxide labeling of mesenchymal stem cells (MSCs), (2) evaluate if ferumoxide labeling allows in vivo tracking of matrix-associated stem cell implants (MASIs) in an animal model, and (3) compare the magnetic resonance imaging (MRI) characteristics of ferumoxide-labeled viable and apoptotic MSCs. MSCs labeled with ferumoxide by simple incubation, protamine transfection, or Lipofectin transfection were evaluated with MRI and histopathology. Ferumoxide-labeled and unlabeled viable and apoptotic MSCs in osteochondral defects of rat knee joints were evaluated over 12 weeks with MRI. Signal to noise ratios (SNRs) of viable and apoptotic labeled MASIs were tested for significant differences using t-tests. A simple incubation labeling protocol demonstrated the best compromise between significant magnetic resonance signal effects and preserved cell viability and potential for immediate clinical translation. Labeled viable and apoptotic MASIs did not show significant differences in SNR. Labeled viable but not apoptotic MSCs demonstrated an increasing area of T2 signal loss over time, which correlated to stem cell proliferation at the transplantation site. Histopathology confirmed successful engraftment of viable MSCs. The engraftment of iron oxide-labeled MASIs by simple incubation can be monitored over several weeks with MRI. Viable and apoptotic MASIs can be distinguished via imaging signs of cell proliferation at the transplantation site.

Health care costs in US patients with and without a diagnosis of osteoarthritis

Background

Osteoarthritis is a chronic and costly condition affecting 14% of adults in the US, and has a significant impact on patient quality of life. This retrospective cohort study compared direct health care utilization and costs between patients with osteoarthritis and a matched control group without osteoarthritis.

Methods

MarketScan^® databases were used to identify adult patients with an osteoarthritis claim (ICD-9-CM, 715.xx) in 2007, and the date of first diagnosis served as the index. Patients were excluded if they did not have 12 months of continuous health care benefit prior to and following the index date, were aged <18 years, or lacked a second diagnosis code for osteoarthritis between 15 and 365 days pre-index or post-index. Osteoarthritis patients were matched 1:1 to patients without osteoarthritis for age group, gender, geographic region, health plan type, and Medicare eligibility. Multivariate analyses were conducted to assess for differences in utilization and costs, controlling for differences between cohorts.

Results

The study sample included 258,237 patients with osteoarthritis and 258,237 matched controls without osteoarthritis. Most patients were women and over 55 years of age. Patients with osteoarthritis had significantly higher pre-index rates of comorbidity than controls. Mean total adjusted direct costs for osteoarthritis patients were more than double those for the control group at US$18,435 (95% confidence interval [CI]: US$18,318–US$18,560) versus US$7494 (95% CI: US$7425–US$7557). Osteoarthritis patients incurred significantly higher inpatient costs at US$6668 (95% CI: US$6587–US$6744) versus US$1756 (95% CI: US$1717–US$1794), outpatient costs at US$7840 (95% CI: US$7786–US$7902) versus US$3675 (95% CI: US$3637–US$3711), and prescription drug costs at US$3213 (95% CI: US$3195–US$3233) versus US$2245 (95% CI: US$2229–US$2262) compared with the controls.

Conclusion

The direct health care costs of osteoarthritis patients were over two times higher than those of similar patients without the condition. The primary drivers of the cost difference were comorbidities and inpatient costs.

An overview of OA research in two urban APLAR populations

Osteoarthritis (OA), the most prevalent type of arthritis in the elderly, is also among the first five leading causes of disability in developed countries. With the 'Westernized' living environment and lifestyle among Southeast Asian urbanized cities, where obesity is on the rise and the populations are ageing, the incidence of OA is expected to rise in the next decades. There is need to summarize research work within these places. This article summarizes some of the research aspects of OA in Southeast Asian cities. These data may form a useful basis for future planning of medical resource and needs.

Osteoarthritis and absenteeism costs: evidence from US National Survey Data

OBJECTIVE

This study seeks to quantify the effects of osteoarthritis on the cost of absenteeism from work.

METHODS

This study performs multivariable analyses to examine the relationships between osteoarthritis and annual cost to employers that is associated with absenteeism. The cost is measured as the probability of absenteeism, days missed from work, and their dollar values, all indirect costs.

RESULTS

Osteoarthritis leads to a significantly higher probability of absenteeism and more days missed from work. Osteoarthritis increases annual per capita absenteeism costs by $469 for female workers and by $520 for male workers. This is equivalent to approximately 3 lost workdays. Aggregate annual absenteeism costs are $10.3 billion (women = $5.5 billion; men = $4.8 billion).

CONCLUSIONS

Aggregate annual absenteeism costs of osteoarthritis are quite substantial as measured by the probability of absenteeism, days missed from work, and their dollar values, compared with other major chronic diseases.