RT Journal Article
SR Electronic
T1 A prospective study of change in bone mineral density over one year in adults with cystic fibrosis
JF Thorax
JO Thorax
FD BMJ Publishing Group Ltd and British Thoracic Society
SP 719
OP 723
DO 10.1136/thorax.57.8.719
VO 57
IS 8
A1 C S Haworth
A1 P L Selby
A1 A W Horrocks
A1 E B Mawer
A1 J E Adams
A1 A K Webb
YR 2002
UL http://thorax.bmj.com/content/57/8/719.abstract
AB Background: Low bone mineral density (BMD) is prevalent in adults with cystic fibrosis. To identify appropriate therapeutic strategies and the optimal time for intervention, it is necessary to document the natural history of cystic fibrosis related low BMD. Methods: 114 adults with cystic fibrosis underwent bone densitometry a median (25–75% interquartile range) of 12 (12–13) months after initial assessment of bone density. BMD was measured in the lumbar spine, femoral neck, total hip, and distal forearm on recruitment to the trial and at follow up. Results: In patients ≤24 years of age (n=55, mean (SD) age 19.5 (2.6) years) in whom an annual increase in BMD would normally be expected, BMD increased by a mean (95% CI) 2.9% (1.6 to 4.2) per year in the distal forearm (p<0.001), but decreased by 2.5% (95% CI –3.8 to –1.2) per year in the femoral neck (p<0.001) and by 2.2% (95% CI –3.3 to –1.0) per year in the total hip (p<0.001). In patients ≥25 years of age (n=59, mean (SD) age 30.3 (5.4) years) in whom no annual change in BMD would normally be expected, BMD decreased by 1.9% (95% CI –2.9 to –0.8) per year in the femoral neck (p<0.001), by 1.5% (95% CI –2.4 to –0.6) per year in the total hip (p=0.001), and by 0.8% (95% CI –1.5 to –0.1) per year in the distal forearm (p=0.026). There was no significant annual change in lumbar spine BMD in either patient cohort. Conclusions: Reduced rates of bone accretion and accelerated rates of bone loss explain the high prevalence of low BMD in adults with cystic fibrosis.