Date Published: July 7, 2017
Publisher: Public Library of Science
Author(s): Ping Zhou, Jian Hu, Ping Xi, Ning Zhang, Bo Yang, Jie Zheng, Xiaoqin Wang, Andrzej T. Slominski.
It has been accepted that vitamin D (VD) plays an important role in bone metabolism. However, the levels of VD in people of different regions are quite different and there is still no final conclusion on the significant correlation between VD and osteoporosis. 245 cases of peri-menopausal women were collected to study the relationship between VD and osteoporosis in western China. The mean value of 25-hydroxyvitamin D for the participants was 14.39 ng/mL. The average values of parathyroid hormone (PTH), calcium (Ca) and phosphorus (P) were 47.62 pg/mL, 2.26 mmol/L and 1.18 mmol/L, respectively. The average value of bone mineral density (BMD) in lumbar vertebrae was -1.20 SD and that in femoral neck was -0.04 SD. Compared with normal group, PTH of VD deficiency group was significantly increased (P < 0.05), Ca was remarkably decreased (P < 0.01) while the BMD between these two groups showed no significant difference (P > 0.05). VD was in positive correlation with the age (P < 0.01) and Ca (< 0.01) of the participants, negative correlation with PTH (P < 0.01) while no significant correlation with the BMD of lumbar vertebrae and femoral neck (P > 0.05). The risk factors resulting in the occurrence of osteoporosis in the lumbar vertebrae of the participants covered Ca increase (OR = 66.247, P<0.05), age growth (OR = 1.194, P<0.01) and menopause (OR = 2.285, P<0.05). This study has found that the status of VD deficiency showed no significant correlation with the level of BMD, which hinted that independent measurement of the bone metabolic markers, including Ca, P, VD and PTH, was difficult to accurately reflect the status of BMD in peri-menopausal women of this region. It’s necessary to combine multi-site bone scanning to diagnose the patients’ status of osteoporosis so as to provide reasonable guidance for early clinical prevention and treatment.
In recent years, researchers have conducted intensive investigations and discussions on the important role of vitamin D in bone metabolism. VD deficiency may lead to rickets in children and chondromalacia in adults, and VD deficiency in elder people and menopausal women will result in bone loss and even the occurrence of osteoporosis and bone fractures [1,2]. Along with the increasing degree of aged phenomenon, the number of people may suffer the prevalence risk of osteoporosis is growing year by year. Timely discovery of VD deficiency or insufficiency and appropriate VD supplement are important means for the prevention and treatment of osteoporosis [3,4]. However, the levels of VD in people from different regions of the world differ greatly due to the influence of these factors, including race, gender, age, lifestyle, eating habits and sunlight exposure of residential region . Recent studies have showed that the levels of VD in people of some regions show no significant correlation with osteoporosis [6–8]. Moreover, meta-analysis has indicated that independent VD supplement presents no therapeutic effect on people with osteoporosis , which hints that the effect of VD in bone metabolism and the incidence of osteoporosis in different regions and ethnic groups may exist differences. In addition, influenced by menopausal factors, perimenopausal women’ endocrine environments are undergoing significant changes and they are easy to suffer from osteoporosis . Therefore, this study is expected to analyze the relation between the indexes, including VD, in perimenopausal women of this region and osteoporosis, and define the risk factors resulting in the occurrence of osteoporosis to perimenopausal women of this region so as to provide clinical guidance for effective prevention and treatment of osteoporosis by investigating the incidence of osteoporosis in perimenopausal women at the age of 40–60 in Xi’an region of Shaanxi province, and the distribution of calcium-phosphorus metabolic indexes including VD, PTH, Ca and P.
Vitamin D is a fat-soluble vitamin, belongs to the sterol compounds. Among all the VD derivatives, activity of vitamin D2 and D3 is the highest. In organisms, vitamin D has no biological activity before the formation of 25(OH)D and 1,25(OH)2D after hydroxylation in certain cells of the liver, kidney and other organs. Moreover, previous study reported that, in addition to animal liver and kidney, novel VD pathways were also found in skin and adrenal gland. VD derivatives generated through these pathways might act as hormones in the regulation of variety of endocrine activities in human body [11, 12, 13]. 25(OH)D, a precursor of 1,25(OH)2D, is the main storage form of vitamin D in the human body and is capable for detecting the VD in the laboratory. Namely, 25(OH)D can be used to determine total VD in human body.