Serum iron deficiency and 25-hydroxyvitamin D deficiency as an independent risk factor for osteoporosis in postmenopausal Arab women

Abstract

Background: Iron deficiency and 25-hydroxyvitamin D (25(OH)D) deficiency are among the most common nutrient deficiencies in the world. Osteoporosis, a major bone disorder, is prevalent globally as well as in Saudi Arabia. The relationship between these micronutrient deficiencies with osteoporosis is less investigated. Hence, the current study aimed to determine the relationship between iron and 25(OH)D deficiencies among postmenopausal Saudi women with osteoporosis and their associations with bone biomarkers. Methodology: A total of 184 postmenopausal Saudi women ≥ 45 years old [N = 75 osteoporosis group; N = 109 without osteoporosis or control group] were enrolled in this cross-sectional study. Anthropometrics and bone mineral density were measured. Serum iron indices, 25(OH)D and bone biomarkers [β-carboxyterminal telopeptide of type 1 collagen (β-crosslap), osteocalcin (OC), osteoprotegerin (OPG), osteopontin (OPN) and bone-specific alkaline phosphatase (BsALP) were determined. Results: In all subjects, significant associations were observed between serum iron and OC (r = 0.19; p = 0.02) as well as OPN (r = 0.17; p = 0.05). Also, serum 25(OH)D was inversely associated with BsALP (r = −0.25; p = 0.02), and positively with β-crosslap (r = 0.38; p = 0.01). An inverse significant association was observed between 25(OH)D and OPG (r = −0.25; p = 0.01) in the control group and BsALP (r = −0.31; p = 0.02) in the osteoporosis group. Conclusion: Significant associations between circulating iron and 25(OH)D with select bone biomarkers were observed in postmenopausal Arab women with osteoporosis, suggesting that these micronutrients may affect bone metabolism.

Keywords

• Iron deficiency
• Vitamin D deficiency
• Osteoporosis
• Postmenopausal
• Arab women