[Prevalence of low bone mineral density in postmenopausal breast cancer survivors]

To evaluate the prevalence of low bone mineral density (BMD) in postmenopausal breast cancer survivors.

In this cross-sectional study, 115 breast cancer survivors, seeking healthcare at a University Hospital in Brazil, were evaluated. Eligibility criteria included women with amenorrhea ≥ 12 months and age ≥ 45 years, treated for breast cancer and metastasis-free for at least five years. BMD was measured by DEXA at the lumbar spine (L1-L4) and femoral neck. Low BMD was considered when total-spine and/or femoral-neck T-score values were <-1.0 Delphi Score (DP) (osteopenia and osteoporosis). The risk factors for low BMD were assessed by interview. Data were analyzed statistically by the χ(2) test and Fisher's exact test.

The mean age of breast cancer survivors was 61.6 ± 10.1 years and time since menopause was 14.2 ± 5.6 years, with a mean follow-up of 10.1 ± 3.9 years. Considering spine and femoral neck, 60% of breast cancer survivors had low BMD. By evaluating the risk factors for low BMD, a significant difference was found in the percent distribution for age (higher % of women >50 years with low BMD), personal history of previous fracture (11.6% with low BMD versus 0% with normal BMD) and BMI. A higher frequency of obesity was observed among women with normal BMD (63%) compared to those with low BMD (26.1%) (p<0.05).

Postmenopausal breast cancer survivors had a high prevalence of osteopenia and osteoporosis.