Association between bone mineral density and clinical consequences: cross-sectional study of Korean postmenopausal women in an orthopaedic outpatient clinic

Abstract

This study is to identify the characteristics of BMD and the related clinical consequences through a nationwide, consecutive, cross-sectional study. A total of 1,281 postmenopausal women was enrolled nationwide and underwent measurement for BMD using dual energy x-ray absorptiometry. Following the T-spine and L-spine plane radiography, they were evaluated for vertebral fracture by a semi-quantitative method using the Genant's method. Relationship between BMD and osteoporotic fracture and a degree of deformity in vertebral fracture, treatment history in osteoporosis and the EQ-5D was analyzed. The distribution of the normal, osteopenia and osteoporosis group was 25.9%, 37.0%, and 37.2% in lumbar spine, and 31.4%, 45.3%, and 23.3% in femur neck, respectively. BMD in subjects with symptomatic or asymptomatic vertebral fracture was significantly lower than those without fracture. The femur neck and total hip BMDs were significantly lower in hip fracture group (0.646 g/cm(2) and 0.643 g/cm(2), respectively) and wrist fracture group (0.661 g/cm(2) and 0.712 g/cm(2), respectively) than in subjects without fracture (0.721 g/cm(2) and 0.712 g/cm(2), respectively). The BMD was significantly lower with more severe degree of deformity in vertebral fracture and lower scores in mobility, usual activities and pain/discomfort of the EQ-5D. In Korean postmenopausal women, the prevalence of osteoporosis and vertebral, hip and wrist fracture increase and quality of life decreases with lower BMD.

Keywords: Bone Density; EQ-5D; Osteoporotic Fractures; Postmenopause; Women.

Fig. 1

T-scores by age group: Box plot. (A) T-score of L-spine. (B) T-score of femur neck. (C) T-score of total hip. With increasing age, the L-spine, femur neck and total hip BMD values significantly decrease.

Fig. 2

The incidence of osteoporotic vertebral compression fracture by T-score. With decreasing T-score, the prevalence of vertebral compression fracture increase.

Fig. 3

Bone mineral density and fracture. (A) The mean BMD values in the L-spine, femur neck and total hip was significantly lower in subjects with osteoporotic vertebral fracture than those without fracture (P < 0.001 for all three). (B) T-scores in the L-spine, femur neck and total hip was also significantly lower in subjects with osteoporotic vertebral fracture than those without fracture (P < 0.001 for all three).

Fig. 4

Bone mineral density and osteoporotic vertebral compression fracture with or without pain. The L-spine and total hip BMD values was significantly lower in vertebral fracture patients with pain than in asymptomatic fracture patients (P < 0.01 for all), and BMD values in the L-spine, femur neck and total hip was significantly lower in asymptomatic fracture patients than those without vertebral fracture (P < 0.01 for all) by analysis of variance.

Fig. 5

Bone mineral density by vertebral deformity grade. The L-spine, femur neck and total hip BMD are significantly higher in the normal group than that in the Genant SQ Grade 1 and the Genant SQ Grade 2 and 3 group (P < 0.01). The femur neck and total hip BMD are significantly higher in Genant SQ Grade 1 than the Genant SQ Grade 2 and 3 (P < 0.01) by analysis of variance (ANOVA).

Fig. 6

Correlation between the EQ-5D index and VAS. The EQ-5D index shows a weak correlation coefficient of r = 0.445 with VAS (P < 0.001).