Background
Low-trauma fractures are the important complications of systemic osteoporosis, which lead to reduced quality of life, increased morbidity, disability and mortality. Nowadays, bone mineral density (BMD) and trabecular bone score (TBS) measured by dual energy X-ray absorptiometry are two major parameters of bone strength. They are widely used when establishing the osteoporosis diagnosis. The purpose was to study the frequency and localization of different osteoporotic fractures in postmenopausal women depending on the age, BMD and TBS.
Materials and methods
We have performed cross-sectional study and have examined 1,369 postmenopausal women aged 45–89 years. Patients were divided into groups depending on BMD according to the WHO criteria: normal bone (T-score > –1.0 standard deviation (SD)), osteopenia (≤ –1.0 T-score £ –2.5 SD), osteoporosis (T-score ≤ –2.5 SD), and depending on TBS (L1-L4) quartiles (groups): QI — the lowest quartile (0.36–1.08); QII — the lower quartile (1.08–1.20); QIII — the upper quartile (1.20–1.32); QIV — the highest quartile (1.32–1.79). BMD and TBS in lumbar spine (L1-L4) were measured using Prodigy densitometer (GE Medical systems, Lunar, model 8743, 2005). TBS was determined using the software TBS Insight (Med-Imaps, Bordeaux, France, 2006).
Results
Our study found that risk of all types of osteoporotic fractures in females reliably increases with age (for vertebral fractures — by 1.97–4.26 times, non-vertebral — 1.96–5.45 times, combined fractures — 1.54–3.14 times). Additionally, we have revealed that osteoporotic fractures are present in all groups of females with different BMD: osteoporosis (45.5 %), osteopenia (26.9 %) and normal bone (18.1 %). The highest frequency of osteoporotic fractures was detected in osteoporosis (46.5 %), and, predominantly, in women with vertebral and combined fractures. Only 25.5 % of patients with non-vertebral fractures have osteoporosis. Low TBS was observed in 50.8 % of females with vertebral, 43.7 % — non-vertebral and 32.8 % — with combined (vertebral and non-vertebral) osteoporotic fractures.
Conclusions
Osteoporotic fractures are partly associated with age, BMD and TBS. However, there are other significant factors, which influence the risk of fractures, and their combination requires further study.
