Osteoarthritis (OA) has become a major public health problem not only because of increasing prevalence worldwide (about 21 million people affected in the United States) but also frequent association with cardiovascular diseases-the leading cause of death in the industrialized countries.

1. Metabolic Abnormalities observed in Osteoarthritis
of Knee: A single center experience

2. a p o l l o m e d i c i n e x x x ( 2 0 1 3 ) 1 e3
Available online at www.sciencedirect.com
journal homepage: www.elsevier.com/locate/apme
Original Article
Metabolic abnormalities observed in osteoarthritis
of knee: A single center experience
Alakes Kumar Kole a,*, Rammohan Roy b, Dalia Chanda Kole c
a
Associate Professor, Department of Medicine, North Bengal Medical College & Hospital, Darjeeling, West Bengal,
India
b
Clinical Tutor, Department of Medicine, Infectious Diseases Hospital, 57 Beliaghata Main Road, Kolkata 10, India
c
Senior Consultant, B P Poddar Medical Research & Hospital, New Alipore, Kolkata, India
article info
abstract
Article history:
Background: Osteoarthritis is the most common type of joint disease and nowadays obesity-
Received 27 June 2013
metabolic syndrome is one of the major risk factors.
Accepted 24 September 2013
Aims and objectives: To observe the different metabolic abnormalities in patients with knee
Available online xxx
osteoarthritis.
Patients & methods: A total of 336 patients suffering from knee osteoarthritis were evaluated
Keywords:
with special reference to different metabolic abnormalities.
Osteoarthritis of knee
Results: The mean age was 45.8 Æ 14.4 years with male: female ratio was 1:1.2. The meta-
Metabolic abnormalities
bolic abnormalities observed were e hyperuricemia in 50 (14.9%), metabolic syndrome in
Risk factors
43 (12.8%), obesity with dyslipidemia in 28 (8.3%), diabetes with dyslipidemia in 25 (7.4%),
obesity in 21 (6.3%), hypothyroidism in 14 (4.2%), diabetes in 13 (3.9%) and dyslipidemia in
10 patients (3%). It had been observed that clustering of metabolic abnormalities were
present in younger patients.
Conclusion: Osteoarthritis is not only a source of discomfort or misery but also may be
associated with various metabolic abnormalities, which are the future predictors of cardiovascular events.
Copyright ª 2013, Indraprastha Medical Corporation Ltd. All rights reserved.
1.
Introduction
Osteoarthritis (OA) has become a major public health problem
not only because of increasing prevalence worldwide (about
21 million people affected in the United States) but also
frequent association with cardiovascular diseases-the leading
cause of death in the industrialized countries.1 Osteoarthritis
changes is seen in almost all people above 75 years of age
whereas at the age of 18e24 years about 7% of men and 2% of
women usually show signs of osteoarthritis changes.2 Recent
concept is that OA is not merely a disease related to aging or
mechanical stress of joints, rather a metabolic disorder sharing
similar biochemical as well as inflammatory profile contributing to both the initiation and progression of the disease
process.1,3 Hence ‘metabolic osteoarthritis’ may be considered
as a subtype of OA and also the fifth component of metabolic
* Corresponding author. Resident address: Victoria Greens, Flat-A3/204, 385 Garia Main Road, Kolkata 700084, West Bengal, India.
Tel.: þ91 (0) 9830056291.
E-mail addresses: dralakeskole72@gmail.com, dralakeskole@yahoo.co.in (A.K. Kole), royrammohan@yahoo.com (R. Roy), drdaliachanda77@yahoo.co.in (D.C. Kole).
0976-0016/$ e see front matter Copyright ª 2013, Indraprastha Medical Corporation Ltd. All rights reserved.
http://dx.doi.org/10.1016/j.apme.2013.09.001
Please cite this article in press as: Kole AK, et al., Metabolic abnormalities observed in osteoarthritis of knee: A single center
experience, Apollo Medicine (2013), http://dx.doi.org/10.1016/j.apme.2013.09.001

3. 2
a p o l l o m e d i c i n e x x x ( 2 0 1 3 ) 1 e3
syndrome.4 It had been reported that obesity is one of the
major modifiable risk factors attributing to the development of
knee osteoarthritis (elevated adipokines) by inducing the
expression of proinflammatory factors as well as degradative
enzymes leading to the inhibition of cartilage matrix synthesis
and stimulation of subchondral bone remodeling.5 Hyperglycemia (advanced glycation end-products), by oxidative stress
and also by inducing low-grade systemic inflammation, is
responsible for cartilage damage, whereas dyslipidemia may
initiate development of OA due to abnormal lipid metabolism
(ectopic lipid deposition). Moreover, hypertension can cause
subchondral ischemia compromising nutrient exchange and
triggering bone remodeling leading to osteoarthritis. Metabolic
syndrome was reported to be more prevalent in younger
individuals suffering from knee osteoarthritis regardless of
sex or race and the development of osteoarthritis at the age
of 44 years was associated with a five fold increased risk of
metabolic syndrome.6 Moreover, presence of more than one
metabolic risk factors was associated with more chances of
development and also progression of knee osteoarthritis.7
A recent study showed that patients suffering from knee OA
had twofold increased risk of availing sick leave and also
40e50% increased risk of disability pension benefit compared
to the general population.8 Moreover osteoarthritis, particularly in the younger individuals, is really a source of discomfort
and misery, often due to the fact that it prevents and hinders
an otherwise healthy individual taking part in activities they
might usually enjoy due to its significant impact on quality
of life.9
The objective of this study was to observe different
metabolic abnormalities in patients suffering from knee
osteoarthritis.
Table 1 e Different metabolic abnormalities in patients
with knee OA.
Risk factors
Hyperuricemia
Metabolic syndrome
Obesity þ dyslipidemia
Diabetes þ dyslipidemia
Obesity
Hypothyroidism
Diabetes
Dyslipidemia
Patients and methods
This was a cross sectional observational study done in North
Bengal Medical College & Hospital, Darjeeling, India from
January ’2009 to January ’2011. A total number of 342 patients
suffering from knee osteoarthritis (diagnosed as per the ACR
criteria) were randomly selected from rheumatology clinic and
six of them were excluded because of recent history of trauma
to knee joint. The enrolled patients were evaluated in respect
to their complaints, occupation, food habits, body mass index
(BMI), waist hip ratio, blood pressure, and any history of
operation or injury involving knee joints in past or any
congenital bony abnormality. Blood biochemistry including
fasting blood glucose, serum uric acid, lipid profile and thyroid
function tests were done. Consent for this study was taken
from each patient and ethical approval done. Data were
collected and analyzed in respect to different metabolic abnormalities and metabolic syndrome was diagnosed as per
National Cholesterol Education Program (NCEP-ATPIII) criteria.
3.
Results
In this study the mean age was 45.8 Æ 14.4 years with the male:
female ratio was 1:1.2 and the mean BMI was 24.34 Æ 4.45 kg/
m2. The occupation of these patients were office workers -112
50
43
28
25
21
14
13
10
(14.9%)
(12.8%)
(8.3%)
(7.4%)
(6.3%)
(4.2%)
(3.9%)
(3%)
(33.3%), shopkeepers -95 (28.2%), labors -39 (11.6%), retired
persons -33 (9.8%), farmers -27 (8%), house wives -21 (6.2%)
and students -9 (2.7%). Majority of these patients were
observed to have history of consumption of high calorie diet
and less physical activity. The different metabolic abnormalities observed were e metabolic syndrome in 43 (12.8%),
obesity and dyslipidemia in 28 (8.3%), diabetes and dyslipidemia in 25 (7.4%), obesity in 21 (6.3%), hypothyroidism in
14 (4.2%), diabetes in 13 (3.9%) and dyslipidemia in 10 patients (3%) [Table 1]. The mean triglyceride level was
221.24 Æ 58.56 mg/dl, HDL was 32 Æ 4.2 mg/dl, LDL level was
112 Æ 24.56 mg/dl and mean uric acid was 6.8 ± 1.3 mg/dl. The
other co morbidities/ inflammatory diseases /events observed
were e hypertension in 36 (10.7%), past history of knee joint
injury/operation in 19 (5.6%), inflammatory joint diseases in 12
cases (3.6%) [rheumatoid arthritis in 8, ankylosing spondylitis
in 3 and mixed connective tissue disease in one].
4.
2.
No of patients (%)
Discussion
In this study it had been observed that metabolic abnormalities were present in different combinations in a total of 46% of
patients suffering from knee OA and importantly clustering of
these metabolic abnormalities were present below 50 years of
age group (26%) which was epidemiologically significant. Hyperuricemia was the most common metabolic abnormality
observed in this study and it had been reported that high
serum uric acid was associated with metabolic syndrome and
its components.10 Metabolic syndrome was detected in 12.8%
patients and they were mainly office workers or shopkeepers
with sedentary lifestyle. Moreover, it had been also observed
that majority of these patients had suffered much from pain,
stiffness and restricted movement of knees requiring
repeated outpatient visit, long absence from works particularly in younger patients and also hampering social activities.
Diabetes and primary hypothyroidism were the two major
endocrine disorders observed in 3.9% and 4.2% cases of knee
OA in this study and strict control of these abnormalities are
essential to control OA. Though in this present study metabolic abnormalities were not so uncommon but more population based studies are needed to establish whether these are
merely associated or as risk factors for knee OA.
Hence, maintaining ideal body weight along with regular
exercise and consumption of low calorie/high fiber diet are
all may be considered as primordial prevention for development of metabolic abnormalities. Moreover continuous
Please cite this article in press as: Kole AK, et al., Metabolic abnormalities observed in osteoarthritis of knee: A single center
experience, Apollo Medicine (2013), http://dx.doi.org/10.1016/j.apme.2013.09.001

4. a p o l l o m e d i c i n e x x x ( 2 0 1 3 ) 1 e3
counseling with reinforcement for weight loss in already
obese individuals along with regular metabolic screening and
appropriate management of already developed metabolic
abnormalities are all the essential steps in patients suffering
from osteoarthritis of knee to decrease future cardiovascular
events and also possibly the development and/or progression
of osteoarthritis.
Conflicts of interest
All authors have none to declare.
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Please cite this article in press as: Kole AK, et al., Metabolic abnormalities observed in osteoarthritis of knee: A single center
experience, Apollo Medicine (2013), http://dx.doi.org/10.1016/j.apme.2013.09.001

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