Prevalence and associated factors of reduced bone mineral density in patients with idiopathic inflammatory myopathies.
OBJECTIVE
To determine the prevalence and identify the associated factors of reduced bone mineral density (BMD) in patients with idiopathic inflammatory myopathies (IIMs).


METHODS
Existing patients diagnosed to have IIMs were recruited for measurement of BMD by dual energy X-ray absorptiometry. Demographic, clinical and treatment variables of these patients were recorded. The prevalence of osteopenia and osteoporosis were calculated. Using multivariate analysis, the independent associated factors for reduced BMD were evaluated.


RESULTS
Thirty-eight patients with IIMs completed the study with 32 (84.2%) being female. The mean age of the patients was 52.8 ± 13.0 years. Nine (23.7%) patients had osteoporosis and 18 (47.4%) had osteopenia. Multivariate analysis revealed female gender and low serum albumin levels at onset were associated with lower spinal BMD. For femoral neck, the factors associated with lower BMD were high Myositis Disease Activity Assessment Visual Analogue Scales (MYOACT) score and high cumulative prednisolone dose.


CONCLUSIONS
Reduced BMD is prevalent in patients with IIMs. Female gender, low serum albumin level at onset, high disease activity and high cumulative corticosteroid dose appeared to be the independent associated factors. Regular assessment of BMD is advisable. The use of anti-osteoporotic and steroid-sparing agents should be encouraged.
Department of Medicine and Geriatrics, Kwong Wah Hospital, Kowloon, Hong Kong.
Ho
H
So
Department of Medicine and Geriatrics, Kwong Wah Hospital, Kowloon, Hong Kong.
Man Lung
ML
Yip
Department of Medicine and Geriatrics, Kwong Wah Hospital, Kowloon, Hong Kong.
Andrew Kui Man
AK
Wong
D015502:Absorptiometry, Photon; D000305:Adrenal Cortex Hormones / Q000009:adverse effects; D000328:Adult; D000368:Aged; D015519:Bone Density; D001851:Bone Diseases, Metabolic / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D003430:Cross-Sectional Studies; D005260:Female; D006723:Hong Kong / Q000453:epidemiology; D006801:Humans; D034141:Hypoalbuminemia / Q000453:epidemiology; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009220:Myositis / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology*; D010024:Osteoporosis / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D015995:Prevalence; D012307:Risk Factors; D012737:Sex Factors
D000305:Adrenal Cortex Hormones
idiopathic inflammatory myopathies; osteopenia; osteoporosis; reduced bone mineral density