RESEARCH - Antiresorptives for osteoporosis may also benefit OA

[Guest guest]

Antiresorptives for osteoporosis may also benefit osteoarthritis

Rheumawire

November 23, 2004

Memphis, TN - The changes in periarticular bone that accompany

cartilage degradation in knee osteoarthritis (OA) were slowed or

prevented by antiresorptive therapy with estrogen or alendronate

(Fosamax, Merck), and, in the case of alendronate, this improvement was

accompanied by a reduction in knee pain, Dr D Carbone and

colleagues report in the November 2004 issue of Arthritis & Rheumatism

[1].

" [O]lder women who were receiving estrogen or alendronate had

significantly fewer OA-related subchondral bone abnormalities in the

knee, including bone attrition and bone-marrow-edema-like abnormalities,

compared with women who were not taking any bone antiresorptive drugs.

Those receiving alendronate also had less knee pain, " they write.

Carbone tells rheumawire: " As a practicing rheumatologist, I think

the take-home message is that the use of antiresorptive agents may also

have applications in arthritis, although further studies, with

longitudinal designs, are needed before any definite statements in this

area can be made. "

" There are insufficient data to prescribe alendronate or any other

antiresorptive agent for the treatment of OA, " she adds. " If, however, a

person is taking alendronate for an accepted indication, ie,

osteoporosis, it is theoretically possible that over the long run, there

may be benefits on OA of the knee, but this awaits confirmation. "

This study was conducted in postmenopausal women participating in

the Health, Aging and Body Composition study and focused on 818 subjects

who reported symptoms of knee OA. These women underwent MRI and

radiography of the knee and were compared with control subjects who did

not have significant knee symptoms.

In the knee-OA subgroup, 214 women (26.2%) were taking

antiresorptive drugs, ie, they reported using estrogen, raloxifene, or

any bisphosphonate during the 2 weeks before study enrollment.

Previous studies have shown that knee MRI evidence of increased

bone turnover, subchondral bone-marrow-edema-like lesions, and bone

attrition are predictors of the worsening of knee OA [2]. The purpose of

this cross-sectional study was to examine the association between

antiresorptive therapy and knee symptoms, radiographic changes, and MRI

changes, the authors explain. Pain was assessed using the Western

Ontario and McMaster Universities Osteoarthritis (WOMAC) Index.

Regression analyses were adjusted for age, race, study site, body mass

index (BMI), use of nonsteroidal anti-inflammatory drugs (NSAIDS), use

of thiazide diuretics, calcium supplementation, bone mineral density

(BMD) of the hip, current smoking status, knee extensor strength,

self-report of osteoarthritis, self-report of fracture since age 45, and

use of a walking device.

There was no association between overall antiresorptive use and

the presence or absence of knee symptoms or with the presence or absence

of radiographic OA, the authors report. Antiresorptive use was

associated with decreased likelihood of subchondral bone attrition and

subchondral bone-marrow abnormalities, and alendronate use was

associated with significantly lower WOMAC pain scores (p=0.02).

Carbone commented to rheumawire that if the sample size had been

larger, the other agents may have also shown an effect on pain.

" In this cross-sectional analysis of elderly African American and

white female participants from the Health ABC Study, use of bone

antiresorptive agents was associated with significantly fewer

subchondral bone attrition and bone-marrow abnormalities of the knee as

assessed by MRI, suggesting a potential beneficial effect on knee OA, "

the researchers concluded. The biological mechanisms behind this effect

might include decreasing subchondral bone resorption and/or decreasing

inflammation.

" These data need to be subjected to a longitudinal study, " Carbone

tells rheumawire. One interesting study to carry out in the future would

be a clinical trial of alendronate use vs no use, with MRI parameters

and WOMAC scores as end points in patients without advanced OA to begin

with, but " I can think of several others as well, " she says.

Janis

Sources

1. Carbone LD, Nevitt MC, Wildy K, et al. The

relationship of antiresorptive drug use to structural findings and

symptoms of knee osteoarthritis. Arthritis Rheum 2004; 50:3516-3525.

2. Felson DT, McLaughlin S, Goggins J, et al. Bone

marrow edema and its relation to progressive knee osteoarthritis. Ann

Intern Med 2003; 139:330-336.

I'll tell you where to go!

Mayo Clinic in Rochester

http://www.mayoclinic.org/rochester

s Hopkins Medicine

http://www.hopkinsmedicine.org