O41 Percentage body fat as a predictor for fragility fracture: an observational study

Abstract

Abstract Background A body mass index (BMI) of less than 19 is a known risk factor for the development of osteoporosis and thus increases the propensity of one having a fragility fracture. Bone mineral density (BMD) referrals are aided by the FRAX™ tool, which contains BMI in order to calculate the ten-year fracture risk. We aimed to investigate the effect of percentage body fat on risk of fracture referred for BMD estimation. Methods Between June 2004 and October 2015, patients were referred for bone mineral density (BMD) estimation in a scanner in the North West of England. All patients were referred with all FRAX™ indications including rheumatoid arthritis, excess alcohol, steroids, family history of fracture and secondary osteoporosis. The cohort was divided into quintiles of ascending body mass percentage. Logistical regression was then applied before adjusting for age at scan, gender and total left BMD comparing patients with a fracture and those that had not. Results 35,759 patients were referred for scanning during the period. 22,765 (63.66%) were referred for BMD estimation and had body fat percentage measured. Mean age at scan was 63.16 (SD 12.86) and 18,961 (88.29%) of the cohort were females. 8,072 (35.46%) had a fracture. More fractures were seen in higher quintiles of percentage body fat, 1,693 (20.97%) compared to 1,580 (19.57%) in females (p = <0.05). Predictors shown in the Table 1 below adjusted for age at scan, gender and total left BMD. Logistical regression of the quintiles after adjustment shows statistical significance in quintiles 3, 4 and 5 as well as for age at scan and total left BMD. Other predictors did not shows statistical significance p > 0.05. Conclusion Our study of 22,765 patients referred for BMD estimations opposes current literature on the effect of BMI on fragility fractures. The data shows that increasing percentage body fat in associated with an increased propensity of fragility fractures in those with BMI as a FRAX™ indicator. Currently percentage body fact is not featured in the FRAX™ tool and further work needs to be done to show the relationship between fracture risk and percentage body fat. Disclosures D.T. Beith: None. M. Bukhari: None.