Background Women with breast cáncer (BC) are at risk for the development of bone loss and osteoporosis (OP) mainly due to adjuvant therapies, as aromatase inhibitors (AI). Thus, it would be of special interest in this group of patientes, to know at baseline wich factors can predispose to develope fragility fractures (FF) during follow-up, in order to optmize vigilance and treatment.
Objectives The purpose of this study is to analyze wich risk factors at baseline that can predict the appereance of a new FF in women with BC and OP.
Methods Retrospective analysis of consecutive female patients with recent breast cancer (BC) and low bone mineral density (BMD) referred to the osteoporosis outpatient clinic for assessment, as agreed with oncologists. Fort he purpose of this anaylisis, only patients with follow-up data (at least six months after baseline visit) were selected. FRAX tool -derived risk factors (age, BMI, DEXA, previous fracture, parent fractured hip, smoking, alcohol, glucocorticoids, rheumatoid arthritis, secondary OP) were taken as explicative variables. Student's t and chi-2 tests were used to perform comparisons base don the appereance of new FF in the study period.
Results A total number of 156 female patients have been assessed up to January 2017. Of the 107 patients in follow-up (68.5%; median time in follow-up 2.1 years p25–75 1.2–3.2). Median age was 62.07 years old (SD±10,35), being 89% of them postmenopausal. 73 (68,2%) were on AI therapy (10 anastrozole, 59 letrozole and 4 exemestane). At baseline, 29 patients (27.1%) showed a FF (15 vertebral; 10 non vertebral; 2 hip; 2 multiple fracture). Antiosteoporotic treatment was recommended in 95 patients (88.7%). During follow-up, 13 FF were seen (12,1%; CI95% 6–19); being 8 of them vertebral, 4 not vertebral, and one multiple fracture; no new hip FF was seen.
After comparison of the different risk factors according to the development of a new FF, no significant association was found (see table).
Conclusions In this study no relationship between FRAX-based risk factors and the development of new FF in women with OP and BC was found. As new FF occurred in 12% of cases, it highlights the need for special attention to this singular, secondary form of OP.
Kanis JA, Johnell O, Oden A, Jonsson B, Dawson A, Dere W. Risk of hip fracture derived from relative risks: an analysis applied to the population of Sweden. Osteoporosis International 2000; 11: 120–127.
Disclosure of Interest None declared