Osteoporosis in rheumatoid arthritis. A monozygotic co-twin control study.
OBJECTIVE
To quantify the magnitude and distribution of osteoporosis in rheumatoid arthritis (RA).


METHODS
Bone mineral density (BMD) was measured by dual x-ray absorptiometry, in a monozygotic co-twin control study.


RESULTS
BMD was reduced at most skeletal sites in the twin with RA compared with the co-twin (lumbar spine 4.6%, femoral neck 9.7%, total body 5.7%). Differences in lean soft tissue (5.6% for total body) correlated with differences in BMD between twins at multiple sites.


CONCLUSIONS
Osteoporosis in RA is generalized and may be related to loss of mobility or muscle mass associated with the disease.
Sambrook
P N
PN
Garvan Institute of Medical Research, St. Vincent's Hospital, Sydney, Australia.
Spector
T D
TD
Seeman
E
E
Bellamy
N
N
Buchanan
R R
RR
Duffy
D L
DL
Martin
N G
NG
Prince
R
R
Owen
E
E
Silman
A J
AJ
D001172:Arthritis, Rheumatoid / Q000150:complications / Q000453:epidemiology* / Q000235:genetics; D015519:Bone Density / Q000502:physiology; D004200:Diseases in Twins / Q000453:epidemiology* / Q000235:genetics; D005260:Female; D005272:Femur Neck / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D008159:Lumbar Vertebrae / Q000473:pathology / Q000503:physiopathology; D008297:Male; D010024:Osteoporosis / Q000150:complications / Q000453:epidemiology* / Q000235:genetics; D012042:Registries; D012044:Regression Analysis; D011795:Surveys and Questionnaires; D014430:Twins, Monozygotic; D006113:United Kingdom / Q000453:epidemiology