Background A high prevalence of densitometric osteoporosis (OP) and fractures have been reported in postmenopausal women with breast cancer (BC). Although a multifactorial origin has been proposed, in recent years this has been associated almost exclusively with the use of aromatase inhibitors (AI).
Objectives To determine the prevalence of morphometric vertebral deformities (MVD), and describe and analyse the clinical features and bone mineral density (BMD) in postmenopausal women with BC treated with AI at a tertiary hospital in Spain.
Methods We performed a cross-sectional study including 104 postmenopausal women seen consecutively at the monographic consultation of osteoporosis of our centre, during the period of 2012-2014. Collected data included demographics, neoplastic disease and risk factors for osteoporosis. Dual-energy X-ray absorptiometry of lumbar spine (LS) and femoral neck (FN), and plain X-rays of lumbar and thoracic spine were performed in all patients. Data were analysed using SPSS version 20 software.
Results The mean age of the patients was 66.8±8.02 years and most of them were diagnosed with stages I and II of BC (84%) and less frequently stage III (15.3%); 63.5% received previously chemotherapy. The most commonly used AI were letrozole, anastrozole and exemestane (69.2%, 26% and 4.8% respectively); the mean time of exposure to AI was 24.62±11.9 months (≤24 months 61.2%, >24 months of 38.8%). The global prevalence of MVD was 10.8%. Using WHO 1994 definition for OP, 14 patients (13.6%) had OP in the FN and 34 patients (33.3%) in LS. The distribution of OP at FN according to age range was from 50-59 years: 14.28%, 60-69 years - 4.25%, and 70-80 years: 21.87%; the distribution of OP at LS was from 50- 59 years: 33.3%, 60-69 years: 25.5%, and 70-80 years: 41.9%. The frequency of OP at FN 12.6% in patients with AI ≤24 months and 15% in those with AI >24 months. There was no association between the time of exposure to AI and T-score at FN (p=0.4). The use of proton pump inhibitors (PPI) and statins in our study population was 33.7% and 26.9%, respectively. There was no association between BMD and the use of these drugs; the mean value of BMD at CF was 0.617 g/cm2 in the group with PPI and 0.688 g/cm2 without PPI (p=0.42), and 0.666 g/cm2 and 0.688 g/cm2 in the groups with and without statins, respectively (p=0.33).
Conclusions The prevalence of MVD in this study was 10.8%, similar to the European prevalence in healthy women >50 years old. The frequency of OP in patients with AI treatment in the age group 50-59 years is greater than the population of Spanish healthy women in the same age range (14.28% vs 1.3% at FN, and 33.3% vs 9.09% at LS). Lower BMD in the age group 70-80 years was evident, but it was similar to the Spanish healthy population of the same age group. No significant association was found between lower BMD and time of exposure to AI, or the concomitant use of statins and PPI.
Disclosure of Interest None declared