RT Journal Article SR Electronic T1 Reduced bone density in cystic fibrosis: ΔF508 mutation is an independent risk factor JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP 54 OP 61 DO 10.1183/09031936.04.00050204 VO 25 IS 1 A1 S. J. King A1 D. J. Topliss A1 T. Kotsimbos A1 I. B. Nyulasi A1 M. Bailey A1 P. R. Ebeling A1 J. W. Wilson YR 2005 UL http://erj.ersjournals.com/content/25/1/54.abstract AB The aim of this cross-sectional study was to determine the prevalence and identify determinants of reduced bone mineral density (BMD) in adults with cystic fibrosis (CF). Adults (88) with CF (mean±sd age 29.9±7.7 yrs; forced expiratory volume in one second (FEV1) 58.2±21.5% of the predicted value) were studied. BMD at the lumbar spine (LS) and femoral neck (FN) and body composition were measured using dual-energy X-ray absorptiometry. Blood and urine were analysed for hormones, bone turnover markers, and the cytokines tumour necrosis factor-α, and interleukin-6 and -1β. FEV1 (% pred); CF genotype; malnutrition; history of growth, development or weight gain delays; and corticosteroid use were analysed. BMD Z-scores were −0.58±1.30 (mean±sd) at the LS and −0.24±1.19 at the FN. Z-scores of <−2.0 were found in 17% of subjects. Subjects who were homozygous or heterozygous for the ΔF508 mutation exhibited significantly lower Z-scores than those with no ΔF508 allele. Multiple linear regression showed that the ΔF508 genotype and male sex were independently associated with lower BMD at both sites. Other factors also independently associated with lower BMD included malnutrition, lower 25-hydroxyvitamin D level, lower fat-free mass and lower FEV1 (% pred). In conclusion, reduced bone mineral density in cystic fibrosis is associated with a number of factors, including ΔF508 genotype, male sex, greater lung disease severity and malnutrition.