Predictors of fragility fracture and low bone mineral density in patients with a history of parental fracture

OBJECTIVES: Bone mineral density (BMD) and fragility fracture (FF) have high heritability, but few data exist on impact of other factors on families with fracture history. We aimed to evaluate predictors of FF and low BMD, in patients with family history of FF. METHODS: This was a retrospective study on patients undergoing dual energy X-ray absorptiometry at a district general hospital (DGH), 2004–2016. Parameters recorded (in addition to standard dual energy X-ray absorptiometry parameters): age, smoking, alcohol, corticosteroids, aromatase inhibitors, Depo-Provera, hormone replacement therapy, rheumatoid arthritis, polymyalgia rheumatica, breast or prostate cancer, coeliac disease, and fracture site. Logistic regression was used to model fracture risk and site, and linear regression for impact of factors on L1–4 and femoral BMD. Factor analyses with polychoric correlation matrices and calculation of Eigenvalues were applied to determine association between fracture sites and associated risk factors. RESULTS: A total of 6053 patients were included, 91.1% female. 2094 had sustained at least one FF. Smoking, alcoholism, increased age, height, and fat mass increased FF risk. Sites analysed: femur, tibia/fibula, humerus, forearm, ribs, and vertebrae. Alcoholism, and increasing tissue thickness and fat mass significantly increased FF risk. Decreased right femoral and vertebral BMD increased overall FF risk. CONCLUSIONS: Our study confirms the effect of certain factors on vertebral BMD, but suggests a differential effect on the upper and lower spine, as well as in the dominant and nondominant hip. Different sites of fracture are associated with different risk factors, the most common sites of fracture being the peripheral long bones and vertebrae.