Role of Underweight and Overweight in the Development of Vertebral Pain Syndrome in Systemic Osteoporosis

Abstract

A well-known risk factor for osteoporosis and fractures is weight, so its derivative — body mass index (BMI) — has been added to FRAX model. Numerous studies have shown a correlation between body mass index and risk of fractures. However, correlation and peculiarities of vertebral pain syndrome course in women of older age groups with systemic osteoporosis weren’t studied, that was the purpose of this work. Object of the study: 1028 postmenopausal women over 50 years old, divided into groups depending on bone mineral density (BMD) and body mass index. Methods of the Study. The presence and severity of pain syndrome were assessed in the thoracic and lumbar spine using a visual analogue scale (VAS). BMI is calculated by the standard method based on measurements of body weight and height. BMD at the lumbar spine level was determined using dual-energy X-ray densitometer Prodigy (GE Medicalsystems, Lunar, model 8743, 2005). Statistical analysis was performed using parametric and nonparametric methods. The critical level of significance when testing statistical hypotheses considered p < 0.05. Results of the Study. The level of pain in the thoracic region in patients with systemic osteoporosis and osteopenia system against the background of underweight was significantly higher compared with the corresponding parameter in women with normal BMD. In women with systemic osteoporosis, BMI significantly negatively correlates with the level of pain in the thoracic spine and increases twice the risk of pain in this region compared with patients with normal BMD (risk ration (RR) = 2.00; 95% confidence interval (CI) 1.23–3.27; p = 0.005). The presence of obesity on the background of systemic osteoporosis does not change the risk of pain in the thoracic region (RR = 0.95; 95% CI 0.67–1.32; p = 0.75). In women with osteoporosis we have found significantly higher level of pain in the lumbar spine in a group of obese women compared with the group with normal body weight. Patients with osteoporosis and pre-obesity had significantly higher level of pain in the lumbar spine compared with group of women, corresponding by BMI, with normal BMD. BMI in women with systemic osteoporosis does not correlate with the severity of pain in the lumbar spine and does not alter the risk of its occurrence (RR = 1.03; 95% CI 0.96–1.12; p = 0.39). Conclusion. Underweight in women of older age groups with systemic osteoporosis is associated with an increased risk and severity of pain syndrome in the thoracic region. Overweight promotes pain in the back, but did not affect the course of pain syndrome in this region of the spine in systemic osteoporosis.

Keywords

• osteoporosis
• body mass index
• pain
• women
• postmenopause