Inhaled corticosteroid use and bone-mineral density in patients with asthma.
BACKGROUND
Inhaled corticosteroids are absorbed into the systemic circulation, but the extent to which they have adverse effects on bone is uncertain. The question is important since 3% of the European population take an inhaled corticosteroid regularly and may do so for many years.


METHODS
We studied the dose-response relation between cumulative inhaled corticosteroid dose and bone-mineral density at the lumbar spine and proximal femur in 196 adults (119 women) with asthma aged 20-40 years. Patients had taken an inhaled corticosteroid regularly for at least 6 months, and had had limited exposure to systemic steroids. Cumulative dose of inhaled corticosteroid was calculated from questionnaires and computerised and written general-practice records, and its effect on bone-mineral density was estimated by multiple regression analysis.


RESULTS
Median duration of inhaled corticosteroid treatment was 6 years (range 0.5-24), and median cumulative dose was 876 mg (87-4380). There was a negative association between cumulative dose of inhaled corticosteroid and bone-mineral density at the lumbar spine (L2-L4), femoral neck, Ward's triangle, and trochanter, both before and after adjustment for the effects of age and sex. A doubling in dose of inhaled corticosteroid was associated with a decrease in bone-mineral density at the lumbar spine of 0.16 SD (95% CI 0.04-0.28). Similar decreases were found at the femoral neck, Ward's triangle, and trochanter. Adjustment for potential confounding factors including physical activity and past oral, nasal, dermal, and parenteral corticosteroids did not weaken the associations.


CONCLUSIONS
This study provides evidence of a negative relation between total cumulative dose of inhaled corticosteroid and bone-mineral density in patients with asthma.
Wong
C A
CA
Division of Respiratory Medicine, City Hospital, Nottingham, UK. czwong@middlemore.co.nz
Walsh
L J
LJ
Smith
C J
CJ
Wisniewski
A F
AF
Lewis
S A
SA
Hubbard
R
R
Cawte
S
S
Green
D J
DJ
Pringle
M
M
Tattersfield
A E
AE
D015502:Absorptiometry, Photon; D000280:Administration, Inhalation; D000328:Adult; D000704:Analysis of Variance; D000893:Anti-Inflammatory Agents / Q000009:adverse effects*; D001249:Asthma / Q000188:drug therapy*; D015519:Bone Density / Q000187:drug effects*; D015986:Confounding Factors, Epidemiologic; D003430:Cross-Sectional Studies; D004305:Dose-Response Relationship, Drug; D005260:Female; D005269:Femur / Q000187:drug effects* / Q000473:pathology; D006801:Humans; D008159:Lumbar Vertebrae / Q000187:drug effects* / Q000473:pathology; D008297:Male; D010024:Osteoporosis / Q000139:chemically induced* / Q000000981:diagnostic imaging / Q000473:pathology; D011877:Radionuclide Imaging; D012044:Regression Analysis; D013256:Steroids; D011795:Surveys and Questionnaires
D000893:Anti-Inflammatory Agents; D013256:Steroids