Osteoporosis and Osteoarthritis 2011 Conference

OSTEOARTHRITIS AND MALE OSTEOPOROSIS: ARE THEY

INVERSELY RELATED?

By

Samia Zaki, Mamdouh Mahfouz, Ahmed Mortagy, Hanan K Abdallah and Hala El

Badawy

Osteoporosis and osteoarthritis are two common age-related skeletal disorders responsible for major health expenses in the elderly.

Lane and Nevett , Arthritis Rheum; 2002

Osteoarthritis

Degeneration of articular cartilage

Osteophytes

Bone wideningSubchondral plate sclerosis

Osteoporosis

Microarchitectural deterioration of bony

tissue

Low bone mass

Bone fragility

Susceptibility to fractures

There is a growing awareness that osteoporosis in men is not a rare problem. Men loose bone mineral density at a rate of about 1% per year with advance in age.

Their morbidity and mortality rates from this disease are higher than in other patients.

Hannan et al., J Bone Miner Res, 2000

The current lifetime risk for a fragility fracture is approximately 27% in men aged 50 years or more, and will increase further over the next 20 years.

A twofold to threefold increased risk for death was demonstrated in men with a history of a major osteoporotic fracture versus men without a history of fractures

Ebeling; Treat Endocrinol, 2004

Ebeling; N Engl J Med, 2008

Osteoporosis is undetectable until the onset of fractures, just as hypertension may remain undetected until a serious consequence of untreated hypertension occurs.

Both hypertension and osteoporosis are asymptomatic, but, if left untreated and undetected may lead to their perspective clinical consequences.

Therefore detection of the disease is paramount before the manifestations manifest clinically.

Rochira et al., Eur J Endocrinol, 2006

Secondary causes for osteoporosis are more common in men than women, and require rigorous exclusion and treatment.

Undiagnosed clinical hypogonadism is a common cause of osteoporosis in men, and is readily treatable.

Ebeling; Treat Endocrinol, 2004

Osteoarthritis and osteoporosis are both common conditions in the elderly.

It would be anticipated that the conditions frequently coexist due to their high prevalence, but some studies have suggested that there is an inverse association between the occurrence of OA and osteoporosis.

Lane and Nevett; Arthritis Rheum, 2002

Several epidemiological studies have shown a lower prevalence of osteoporotic hip fractures in patients with osteoarthritis.

Other studies have demonstrated elevated bone mineral density in patients with osteoarthritis.

The prevailing view is that there may be an inverse relationship between osteoarthritis and osteoporosis

The purpose of the present study was to examine the hypothesis that OA and osteoporosis are inversely related in male patients and to assess the testosterone level in all subjects and its relation to osteoporosis in males.

Objective

The study included 40 knee OA male patients and 40 age matched healthy male controls.

Patients with risk factors for secondary osteoporosis were excluded.

All patients and controls had a full history taking and physical examination.

Patients and Methods

Hyperparathyroidism, thyroid disease, intestinal disorders, malignancies, glucocorticoids therapy, immobilization, chronic diseases, drug therapy, or adverse lifestyle practices that increase bone loss

Hyperparathyroidism, thyroid disease, intestinal disorders, malignancies, glucocorticoids therapy, immobilization, chronic diseases, drug therapy, or adverse lifestyle practices that increase bone loss

Bilateral knee examination of all subjects for tenderness, swelling, hard bony tissue enlargement and deformity using the ACR clinical criteria for classification of OA of the knee.

Patients and Methods

Altman et al., Arthritis Rheum, 1986

AP weight bearing knee radiographs, that were scored for: global severity of OA (K&L, range 0-4) presence of osteophytes (range 0-3) joint space narrowing (range 0-3).

Patients and Methods

Spector and Hart; Ann Rheum Dis, 1992

Bone Mineral Density (g/cm2) was measured at the hip, anteroposterior and lateral lumbar spine (L1-L4 spinal region) using DXA.

Osteoporosis was defined by BMD levels, according to the WHO criteria, as 2.5 standard deviations below young adult mean; according to the T-score, and severe osteoporosis when osteoporotic fractures were present.

Patients and Methods

Serum testosterone measurement was done for all patients using an Enzyme Immunoassay, which used a sensitive and specific rabbit anti-human testosterone antibody.

Patients and Methods

In this case-control study the mean age of OA patients was 49.5 ± 13.6 (range: 39-60 yrs) and of the 40 healthy male controls 48.3 ± 9.8 (range: 40-60), they were age matched p>0.05.

OA was bilateral in 16 cases (40%) and unilateral in 24 cases (60%).

Results

Distribution of OA cases and Controls by Body Mass Index

BMIOA Cases, n=40 Controls, n=40

No % No %

Normal 16 43.2 24 66.7

Overweight 16 43.2 8 22.2

Obese 5 13.5 4 11.1

Total 37 100.0 36 100.0

The BMI was not significantly different between the osteoarthritis cases and the control group; p>0.05.

There was no significant difference between OA cases and controls as regards smoking (p>0.05) and life style level of activity (p>0.05).

There was no significant difference between the osteoarthritis cases and the control group as regards incidence of hypertension (p>0.05), or diabetes (p>0.05).

Results

Distribution of Hypertension, diabetes and Thyroid disease among OA cases and Controls

OA Cases Controls Total pHypertension No % No % No %

Present 10 25.6 8 20.0 18 22.8>0.05

Absent 29 74.4 32 80.0 61 77.2

Total 39 100.0 40 100.0 79 100 NS

DiabetesPresent 8 20.0 9 22.5 17 78.8

>0.05Absent 32 80.0 31 77.5 63 21.3

Total 40 100.0 40 100.0 80 100 NS

Thyroid diseasePresent 4 10.0 4 10.0 8 10

>0.05Absent 36 90.0 36 90.0 72 90

Total 40 100.0 40 100.0 80 100 NS

Spine T Score among OA cases and Controls

The difference was non significant; p=<0.05

Hip T Score among OA cases and Controls

The difference was non significant; p=<0.05

Results

Mean BMD ± SDPOA Cases;

n=40Controls;

n=40Spine 0.926 ± 0.164 0.968 ± 0.160 0.251Hip 1.002 ± 0.117 1.00 ± 0.136 0.292

Bone Mineral Density among OA Cases and Controls

The mean bone mineral density in the spine and the femur was not significantly different between the osteoarthritis group and the controls

To ensure that none of the men had undiagnosed clinical hypogonadism, serum testosterone was assessed for all patients and control group.

ResultsMean level of testosterone in OA Cases and Controls

Type Mean ± SD (Mean ± SD) t-test POA

casesn=40

14.35 ± 10.4 1.07 ± 0.232.68 0.007

Controlsn=40

19.65 ± 10.4 1.23 ± 0.25

The mean testosterone level in the osteoarthritis patients was statistically lower than among the control cases (p=0.007)

ResultsMean level of testosterone in Cases with Osteoporosis and Without

Type Mean ± SD POsteoporosis Spine (n=30) 17.11 ± 10.04

>0.05NS

Hip (n=6) 15.76 ± 7.81No

OsteoporosiSpine (n=50) 16.95 ± 10.99

Hip (n=74) 17.09 ± 10.89

The mean testosterone level was not statistically different between cases with osteoporosis and those without osteoporosis

There was no significant difference between OA cases and controls in the frequency of osteoporosis of the spine or hip.

The mean BMD was not statistically different among both groups.

We did not find an association between BMD as measured by DXA and clinical or radiographic features of OA in the knee.

There was no correlation between level of testosterone and osteoporosis.

Results

With multiple logistic regression analysis, knee osteoarthritis was a risk factor for spine osteoporosis; patients with radiological findings diagnostic of osteoarthritis could be 3.5 times at risk of developing spinal osteoporosis.

Smoking and presence of knee OA were risk factors for occurrence of hip osteoporosis.

Results

Almost 40 years have passed since Foss and Byers published their report confirming observations made by orthopedic surgeons on the relative absence of osteoarthritic changes in excised femoral heads from patients who had had hip fracture.

Association between these conditions is still controversial

Foss MVL, Byers PD. Bone density, osteoarthrosis of the hip and fracture of the upper end of the femur. Ann Rheum Dis 1972;31:259-64.

Many studies have been conducted examining the effect of OA on bone density at different sites and with different techniques.

Most of them showed a significant increase in bone mass or bone mineral density in OA cases compared to age-sex matched controls .

Lane and Nevett, Arthritis Rheum, 2002

The Framingham Study (1993)

Examined the BMD of the proximal femur and radius in 932 men and women over 63 yrs of age in relation to knee OA.

The mean femoral BMD, was 5-9% higher in grade 1 and 2 knee OA compared with no knee OA.

The higher BMD was associated with osteophytes, but not joint space narrowing

Hannan MT, Anderson JJ, Zhang Y, Levy D, Felson DT: BMD and knee OA in elderly men and women. The Framingham Study. Arthritis Rheum; 1993

Speculation has been that weight-bearing activities, which are beneficial to the attainment and preservation of peak bone mass, also increase the risk of damage to articular cartilage leading to OA in lower extremity joints.

Another explanation has been that high BMI, which is associated with higher BMD, confers a detrimental biomechanical load to weight-bearing joints, thus leading to OA

The subchondral bone may play an important role in the pathogenesis of OA.

The sclerotic subchondral bone is considered to weaken the articular cartilage by impairing its ability to absorb mechanical shock, thereby influencing the progression of OA.

Li B, Aspden RM: Composition and mechanical properties of cancellous bone from the femoral head of patients with osteoporosis or osteoarthritis. J Bone Mine Res 1997

The Rancho Bernardo Study in 2002

Examined the relation between hand OA and BMD levels (as measured by DXA) among 1779 community-dwelling, ambulatory white adults aged 50-96 years.

OA was not associated with increased BMD levels in men or women. The only significant difference was that women with hand OA had lower hip BMD

Schneider et al. BMD and clinical hand osteoarthritis in elderly men and women: The Rancho Bernardo study. J Rheumatol;, 2002.

In some others, however, no increase was found and in others, bone mass was reduced.

Much of this controversy can be attributed to differences in subject selection, different anatomical sites measured and different methods used in evaluation and expression of the results.

We could not find a relation between osteoarthritis and osteoporosis, but owing to the small number of patients we cautiously conclude that osteoarthritis and osteoporosis are not inversely related.

Conclusion

Conclusion Even though many have shown an

inverse relation between OA and osteoporosis, it does not mean that the 2 conditions are mutually exclusive.

The presence of OA in a joint should not exclude the diagnosis of osteoporosis in a patient.

Thank You

Thank You