The Global Economic Cost of Osteoarthritis: How the UK Compares

Abstract

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.

Full text

Hindawi Publishing Corporation
Arthritis
Volume 2012, Article ID 698709, 6pages
doi:10.1155/2012/698709
Review Article
The Global Economic Cost of Osteoarthritis:
How the UK Compares
A.Chen,C.Gupte,K.Akhtar,P.Smith,andJ.Cobb
MSKLab,ImperialCollege,LondonW68RF,UK
Correspondence should be addressed to A. Chen, alvinm.chen@gmail.com
Received 30 May 2012; Accepted 30 August 2012
Academic Editor: Charles J. Malemud
Copyright © 2012 A. Chen et al. This is an open access article distributed under the Creative Commons Attribution License, which
permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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.
1. Introduction
Musculoskeletal diseases remain one of the most common
causes for severe long-term pain and disability. The increas-
ing significance of musculoskeletal disorders has prompted
the United Nations, the World Health Organization, and 37
countries to spearhead a campaign to recognise and address
the burden of musculoskeletal disorders such as arthritis,
proclaiming it to be the Bone and Joint Decade (2000–2010)
[1], and to advance understanding and treatment of mus-
culoskeletal disorders through prevention, education, and
research.
Within the envelope of musculoskeletal disorders, Oste-
oarthritis represents a complex musculoskeletal disorder
with multiple genetic, constitutional, and biomechanical risk
factors. It represents the most common form of joint disease
and disability in older people and ranks amongst the top 5
causes of disability [2].
The economic costs of osteoarthritis can be broken down
into direct costs and indirect costs. Direct costs represent the
pharmacological/nonpharmacological treatments, including
surgery, as well as use of hospital resources and management
of complications arising from the treatment of osteoarthritis.
Indirect costs represent loss of time from work, decreased
productivity because of pain, care-giver time, premature
mortality, and disability compensation/benefits. These costs
are summarised in Tabl e 1,below.
A third category sometimes considered is that of intan-
gible costs. These are defined as the pain and suffering
experienced by the patient as a result of the disease; the
reduction in the patient’s quality of life. They remain an area
of controversy, with only a few studies making the attempt to
estimate them [3].
2. Aims
The aim of this paper is to examine all relevant literature on
the economic costs of Osteoarthritis in the UK, and to see
what comparisons can be made regarding such costs in the
UK and other countries in North America, Europe, and Asia.

2Arthritis
Tab le 1
Direct costs Indirect costs Intangible costs
Costs of surgery Loss of productivity Pain and suffering
Hospital resources Absenteeism Decreased quality of life
Caregiver time Premature mortality Potential depression/anxiety
Pharmacological and nonpharmacological treatment Disability payments/benefits
Costs of side effects from treatments
Research
3. Methods
A comprehensive review of the literature was performed
using a computerised bibliographical search of MEDLINE
databases from 1946 to 31st Dec 2011. English language
articles were reviewed that contained the words “economic
cost,” “direct cost,” or “indirect cost” in combination with
“osteoarthritis” in either their title or abstract.
To expand the review beyond only published studies,
an internet search was made for publications from the UK
Department of Health, the National Institute for Clinical
Excellence, the UK National Joint Registry, Hospital Episode
Statistics, and charities Arthritis Research (UK) and Arthritis
Care, and all publications were reviewed for information
on costs for osteoarthritis. Further internet searches were
made for publications from the British Orthopaedic Asso-
ciation, the Royal College of Surgeons, the Royal College of
Physicians, and the Royal College of General Practitioners.
Publications from American Association of Orthopaedic
Surgeons and other regional orthopaedic associations in
Europe and Asia were also reviewed.
4. Results
4.1. What Do We Know about OA Costs in North America?
Studies on prevalence of osteoarthritis in the United States
have shown that osteoarthritis affects 13.9% of adults aged
25 and older, and 33.6% of those over the age of 65, with an
approximate 27 million Americans of all ages suffering from
disease [4].
Much of the data available on osteoarthritis in the
United States is derived from studies conducted in the
1960s and 1970s. The Framingham study [5]represented
one of the early studies to associate increasing age with
worsening knee arthritis. This study, which began in 1948,
was initially designed to look at cardiovascular risk factors in
a representative sample of people in the adult population of
Framingham, MA. The study’s patients were examined every
2 years since inception. This same cohort of patients was used
by Felson et al. to look at the prevalence of knee osteoarthritis
approximately 36 years after the start of the study. The age
of the patients in the study ranged from 63 to 94, and a
total of 1805 patients were studied. The study confirmed
that radiographic evidence of OA increased with age, with
a higher prevalence of OA changes in women, as well as a
significantly higher proportion of women with symptomatic
OA.
Lethbridge-c¸ejku et al. [6] examined discharge data
from the National Hospital Discharge Survey and concluded
that Osteoarthritis accounts for 55% of all arthritis related
hospital admissions, with 409 000 such admissions in 1997.
The annual cost of knee and hip replacements in 1997 was
estimated at $7.9 billion (£4.7 billion) [6]. Less than 10 years
later in 2004, the number of hospital admissions had risen to
632 000 and the annual total cost of joint replacements rose
to $22.6 billion (£13.8 billion) [7].
Buckwalter et al. [8] used data drawn from national
data sets collected by the U.S. Bureau of Labor Statistics,
the U.S. National Center for Health Statistics, as well as
existing cost estimates for arthritis in the literature, used
proportional attributable risk models and the human capital
method to break down costs into direct and indirect costs.
From this study, an estimated $3.4–$13.2 billion (£2 billion–
£8 billion) is spent annually on job-related OA costs in the
USA. Meanwhile, Kotlarz et al., in 2010, using evidence from
the national health survey data from 1996–2005, looked at
absenteeism as a result of osteoarthritis. This study, estimated
the indirect cost of the absenteeism to be approximately
US$10.3 billion [9]. The study also confirmed that the costs
for women were larger (US$ 5.5 billion compared to US$4.8
billion), and that absenteeism was less in subjects with lower
education and those in minority groups.
A survey done by Gupta et al, in ON, Canada in 2005,
estimated that the indirect costs incurred by a patient aged
over 55 with hip or knee arthritis may be much higher than
previously estimated when compared to direct costs ($12 990
or £8183 annually for the former, and $2300 or £1449 for the
latter) [10]. Indirect costs were incurred mostly for time lost
from employment and for unpaid informal caregivers, with
caregiver time accounting for 40% of indirect costs. It should
be noted that the authors in this study based the costs on the
monthly wage for a professional homemaker or housekeeper
as caregiver occupation was unknown. This averaged at US$
1278 (£824) per month, which may explain the relatively
higher costs reported.
March and Bachmeier (1997) looked at the global cost of
osteoarthritis and found the cost of osteoarthritis in the USA,
Canada, UK, France, and Australia to account for between 1–
2.5% of the gross national product (GNP) for those countries
[11].
4.2. How Do Recent Studies in Europe Compare? Loza et al.,
in their Spanish study, assessed the burden of knee and
hip osteoarthritis by examining 1071 patients across all the

Arthritis 3
provinces of Spain [12]. The average annual cost for OA
per patient was estimated at C1502 (£1260), with direct
costs representing 86% (£1084) of the total cost. Indirect
costs were much lower (14% or £176) and mainly involved
domestic help.
In contrast to this, the COART study [13]inFrance
attempted to estimate the overall financial cost of osteoar-
thritis to the country. The study concluded that osteoarthritis
remained a major public burden, with direct costs in 2002
exceeding 1.6 billion Euros, about 1.7% of the expenses
of the French Health system. Over 13 million visits were
made to physicians for osteoarthritis. Medication costs were
570 million euros and inpatient treatment amounted to 820
million Euros. During the period of the study, 80 000 total
hip replacements and 38 000 total knee replacements were
performed per year, at a cost of C5600 per THR and C4500
per TKR. The study compared the costs to a previous study
by Levy et al. [14] in 1993 and found that the prevalence of
the disease had risen by 54%, and the direct medical costs by
156%.
In Italy, Leardini et al. examined the economics of
osteoarthritis of the knee in 2004. They used a bottom-
up method, utilising data collected from each patient,
and reviewed patients across 29 medical institutes. They
concluded that the direct costs came to C934 (£785) and
indirect costs C1236 (£1039) per patient per year [15].
4.3. Is the Situation DifferentinAsia? There have been fewer
studies with regard to economic costs of osteoarthritis in
India, China or Southeast Asia compared with countries in
the western hemisphere.
In contrast to the Western literature, Woo et al., in
their Hong Kong [16] study estimated that the cost of
osteoarthritis accounted for 0.28% of the GNP of Hong
Kong, between HK $3.2–$3.9 billion (£253 million–£308
million). The direct costs ranged from HK $4860–$11180
(£384–£883) and indirect costs HK$3300–$6640 (£261–
£525) per person annually.
Xie et al. assessed indirect costs in Singapore for OA
and noted that there were estimated at between US$1000–
1200 (£610–£730), around 2.8% and 3.3% of the annual
household income [3]. The authors here acknowledged that
these costs likely represented the lower end of the scale,
as costs such as loss of productivity of caregivers were
not estimated. The study was also one of the few that
attempted to address and estimate intangible costs using the
willingness to pay (WTP) method. In economics, this model
represents the maximum amount a person would be willing
to pay, sacrifice, or exchange in order to avoid something
undesired, in this case, the pain and suffering associated
with osteoarthritis. The authors here estimated the intangible
costs at US$ 1200 (£775) per year.
4.4. What Do We Know about the Economic Cost of
OA in the UK?
4.4.1. The Prevalence of OA. The Arthritis Research Council
(UK) estimated in 2002 that at least 4.4 million patients
in the UK have X-ray evidence of moderate-to-severe
osteoarthritis in their hands, while 550 000 have similar
evidence of osteoarthritis in their knees, and 210 000 have
evidence of this in their hips [17].
Pye et al., in 2004, showed that almost 8.5 million people
in the UK have X-ray evidence of osteoarthritis in their
spine, with back pain being the most frequent symptom [18].
While predominantly a disease of the elderly, an estimated
6% of adults aged 30 and above have both knee pain and
radiographic changes of osteoarthritis [18].
The Royal College of General Practitioners estimated in
2006 that in the UK over 1 million adults consult their GP
each year with symptoms of osteoarthritis [19]. Another
study in 2007 showed that consultations for osteoarthritis
account for 15% of all musculoskeletal consultations in those
aged 45 and over, rising to 25% in those aged 75 and over
[20]. The cost per consultation is estimated at £36 for a 12-
minute consultation [21].
During the year from 1999-2000, there were 114,500
hospital admissions related to osteoarthritis in the UK
[17]. The latest Hospital Episode Statistics (HES) data
(2010-2011) have shown a significant increase in hospital
admissions, for hip and knee arthritis alone, the combined
figure was 181,350 admissions [20]. When the diagnoses
for polyarthritis and “other arthritis”–but not rheumatoid
conditions or crystal arthropathy are included, the total
number of admissions in 2010/11 was 207,041, representing
an 80% increase compared with figures of 10 years ago.
Surprisingly, there are no published studies in the liter-
ature with regard to direct or indirect costs of osteoarthritis
in the UK. Data, however, is instead only available from a
variety of other sources.
4.5. What Information Is Available from Other Sources about
Costs in the UK?
4.5.1. Direct Costs. The National Institute of Clinical Excel-
lence (NICE) recently published a costing report in 2008
with regard to implementing the guidelines for treatment
of osteoarthritis [22]. In the report, NICE estimated the
prevalence of osteoarthritis in the UK to be a total of 2.8
million patients, based on symptomatic diagnosis in patients
aged over 45. The analysis covered the management of
osteoarthritis in all such patients.
The cost of topical and oral nonsteroidal anti-
inflammatories (NSAIDs) was estimated using prescribing
data from 2005/06 [22]. An estimated 167 000 people
who had a diagnosis of osteoarthritis were found to have
been prescribed topical NSAIDs, and it was estimated that
50% (1.4 million patients) of patients with osteoarthritis
were prescribed oral NSAIDs. The annual cost in 2005/06
of prescribing topical NSAIDs was £8.5 million and £25
million for oral NSAIDs. The cost for topical NSAID
prescriptions was anticipated to double, and the cost of
oral treatment reduced by 10%, if the new guidelines are
followed. Adjusting for inflation, in 2010 prices, this would
equate to £19.2 million and £25.65 million, respectively.
The cost of iatrogenic events related to NSAID use is
also substantial. NSAID-related iatrogenic events have been

4Arthritis
estimated to be between £32–£70 per patient prescribed an
NSAID in the UK. This equates to a total cost of £44.8–£98
million per year (£56.9–£124.4 million at 2010 prices) [23].
The cost of proton pump inhibitor (PPIs) prescription
for use with NSAID treatment was £26 000 in 2005/06 but
expected to rise significantly to £10.5 million (£11.6 million
in 2010) with implementation of the new guidance.
The 2005/06 Hospital Episode statistics stated that the
total number of people aged 45 and over who received
arthroscopic lavage and debridement for knee osteoarthritis
was approximately 20 000. The national tarifffor arthro-
scopies set by the Health Resource Group in 2008/09 was
£1264, resulting in a cost £25 million for such treatment.
It should be noted that NICE expected the cost of this
to fall dramatically (by 19000 patients), with guidelines
restricting the use of arthroscopic treatment to patients
with “mechanical” symptoms such as locking or giving way.
The new cost for arthroscopic treatment of osteoarthritis is
calculated (£1264 ×1000 patients) at £1.26 million (£1.3
million in 2010).
4.5.2. Economics of Joint Replacement. According to the 8th
annual report of the NJR, published September 2011 [22],
a 76 759 primary total hip replacements were performed
in 2010, a 6% increase from 2009. The revision “burden”
was approximately 11% with 7852 hips revised in 2010.
A total of 81979 knee replacements were done in 2010,
representing an increase of 5.7% when compared with 2009.
The revision “burden” here was less, at just over 6% requiring
revision in 2010. The proportion of total knee replacements
to unicondylar knee replacements and patella-femoral knee
replacements have remained largely the same for the last few
years.
While there are other causes for joint replacement
surgery, osteoarthritis remains the most frequent cause for
hip replacement (93% of primary hip replacements in 2010)
and knee replacement (97% of primary knee replacements in
2010).
The costs of hip and knee replacements vary considerably
from trust to trust in the UK with no set national price
for implants, and the cost also being significantly dependant
on length of hospital stay. The tariffreimbursement paid
to the trust in one study [24] in 2005/06 was £6000 for
a primary total hip replacement and £6800 for a primary
total knee replacement. The national tarifffor 2010 was set
at £5552 for an uncomplicated total hip replacement and
£5198 for a similar total knee replacement. This leads to an
estimated cost of £426 million for total hip replacements and
£426 million for primary total knee replacements, giving a
combined total cost for primary hip and knee replacements
of £852 million in 2010. This represents a substantial increase
in costs over the last 10 years, when compared to the
expenditure of £405 million in 2000 for 44 000 hip and 35
000 knee replacements [17]. Even adjusting for inflation, this
cost would only be £514 million in 2010, representing a 66%
increase in the last 10 years. Figure 1 summarises the UK
direct costs.
0
100
200
300
400
500
600
700
800
900
Millions £
NSAIDs
PPIs
Arthroscopy
NSAIDs
PPIs
NSAIDs iatrogenic
Arthroscopy
Joint replacement
NSAIDs
iatrogenic
Joint
replacement
Cost of OA in the UK
44.8 11.6 98 1.3
852
Figure 1
4.5.3. Indirect Costs. Osteoarthritis has a significant negative
impact on the UK economy with an estimated total cost of
1% of GNP [25]. The Department of Work and Pensions
estimates that 36 million work days were lost because
of osteoarthritis in 2002, resulting in a loss of economic
production over £3.2 billion; while at the same time, £43
million was spent on community services and £215 million
spent on social services for osteoarthritis [26].
Arthritis remains the most common condition for people
to receive the Disability Living Allowance (DLA), with £2.41
billion paid to people claiming incapacity benefit due to
arthritis and related conditions in 2001 [26]. More than half
a million people receive the DLA because of arthritis, more
than the total for heart disease, stroke, chest disease, and
cancer combined [16]. Only around 1 in 200 of those on
benefit later returns to work [27].
The most recent review of disability costs in the UK
was done by Dame Carol Black [28] in her review of the
health of the working age population. Unfortunately, the
review did not offer a breakdown of the components in
musculoskeletal disability costs, and so, despite the report,
the exact contribution of OA to such costs in the UK remains
unknown.
5. Discussion
The review demonstrates that osteoarthritis represents an
increasing economic burden to all countries, both from
direct costs and indirect costs. Economic data on osteoarthri-
tis has been made difficult because of problems defining the
prevalence and incidence of the disease. There is only sparse
literature available regarding economic costs in the east, but
what is more surprising is the lack of clear costing studies in
the west, especially in the UK.
Direct costs may vary from country to country, which is
to be expected given their different health systems, and even
between institutions in a country. Significant variability is
seen from these studies, making direct comparison difficult.
Compounding the problem is the fact that the methodology

Arthritis 5
Tab le 2
Author Year of study Country Cost studied
Individual cost per
annum (2010 £) per
OA patient
Population
cost per annum
(2010 £)
McClean et al. 1993 USA Direct costs £1526 US $548 million
Lanes et al. 1994 USA Direct costs £496 N/A
Buckwater et al. 2000 USA Indirect costs N/A £2 billion–£8 billion
Kotlartz et al. 2005 USA Indirect costs £355 £7.25 billion
Maetzel et al. 2000 Canada Direct costs
Indirect costs
£3162
£1407
N/A
N/A
Gupta et al. 2002 Canada Direct costs
Indirect costs
£1768
£9986
N/A
N/A
Loza et al. 2003 Spain Direct costs
Indirect costs
£1292
£209
£4.04 billion
£654 million
Le Pen et al. 2003 France Direct costs £316 £1.58 billion
Leardini et al. 2001 Italy Direct costs
Indirect costs
£ 981
£1299
N/A
N/A
Woo et al. 2001 Hong Kong Direct costs
Indirect costs
£6561
£620
£323 million
(combined cost)
Xie et al. 2005 Singapore Indirect costs £610–£730 N/A
used in estimating these costs can vary from study to study,
and not all studies give a clear breakdown of the calculation
of the direct costs involved [29].
Furthermore, in the studies that provide a breakdown of
the direct costs, few include the cost of alternative therapies
in the treatment of osteoarthritis. There is evidence that
nearly half (47%) of older patients in one American study
[30] used an alternative type of therapy, and these costs are
considerable (US$ 1127 or £723 per annum). Hence, the true
economic burden of direct costs in osteoarthritis is likely to
be significantly higher than most of these studies indicate.
The significant variability in indirect costs from these
studies is also a concern. This is likely to be due to the
lack of a standardized method to estimate indirect costs–
unfortunately, there remains at present no good evidence to
support one preferred method over the others [29]. Most
studies conclude that indirect costs, however, represent a
largely underestimated economic burden to country, and as
such, these estimates may just be the tip of the iceberg.
6. Conclusion
Our review of the literature suggests that while there are a
large number of studies on economic costs of osteoarthritis,
from multiple countries, the information available in the
literature remains patchy and difficult to interpret. Some
studies focus on the macroeconomic angle, looking at costs
at a national scale or costs per capita while others focus on
costs from the view of the individual patient with OA. Other
studies are only specific for arthritis of a single joint. Even
with studies compatible from this point of view, the varied
methodology and lack of standardization of costing make it
impossible to accurately compare economic costs, whether
direct or indirect. These studies are summarized in Tabl e 2.
Despite such difficulties, one conclusion does seem clear
from these studies: that such costs are very substantial and
are continuing to rise.
The continuing lack of published data regarding direct
and indirect OA costs in the UK, especially from the patient
perspective, shows that more research into this area is vital.
This will allow us to fully appreciate the healthcare burden of
OAintheUK,aswellastomakemoreaccuratefinancial
planning for the provision for healthcare services for the
treatment of OA in the subsequent decade to come.
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