Sarcopenic obesity defined by visceral adiposity was associated with osteoporotic vertebral fracture

Previous studies have reported that the fracture risk related to sarcopenic obesity (SO) may be influenced by the distribution of fat mass. Therefore, it is useful to explore a body component suitable for defining obesity when predicting fracture risk. This study was an attempt to explore the contribution of SO defined by visceral adiposity on the incidence of osteoporotic fracture.

We enrolled 736 Chinese patients aged > 60 years in this prospective study. Sarcopenia was defined as low skeletal muscle index (SMI) with muscle strength or low SMI with low physical performance. Obesity was categorized as follows: (1) android to gynoid ratio (A/G ratio, men > 0.82, women > 0.65) as an indicator of visceral adiposity; (2) body fat percentage (men > 27.8%; women > 34.5%); and (3) body mass index (≥ 25 kg/m²). A Cox proportional hazard model was used to determine the association between SO and the risk of osteoporotic fracture.

The incidence of SO was 8.7%; 9.0% in females and 8.1% in males. Of 223 (30.2%) patients with self-reported fractures. SO classified by A/G was associated with an increased risk of osteoporotic vertebral fracture (HR: 1.71, 95% CI: 1.07-2.72). High SMI was associated with a reduced risk of osteoporotic vertebral fracture (HR: 0.82, 95% CI: 0.72-0.93), higher BMI was associated with a higher risk vertebral fracture (HR: 1.12, 95% CI: 0.94-1.63), and higher A/G ratio was associated with a higher risk of any fracture (HR: 1.28, 95% CI: 1.14-1.43) and osteoporotic vertebral fracture (HR: 1.19, 95% CI: 1.05-1.36).

Our findings suggest that SO, defined by visceral adiposity, was associated with the risk of osteoporotic vertebral fracture. Moreover, low SMI, low muscle strength and visceral adiposity were independently associated with osteoporotic fracture.