Supplementary Material for: Anaemia Is Associated with an Increased Risk of Fractures, a Systematic Review, and Meta-Analysis

Background: Anaemia and osteoporotic fractures are both major health problems among older adults worldwide. Objectives: Previous studies suggest that anaemia may be associated with elevated fracture risk among older adults; however, the exact relationship between them is unknown. We aimed to investigate the association between anaemia and fracture risk. Methods: A comprehensive literature search was performed in four medical databases. We included articles that were published from inception to February 18, 2021. Odds ratios (ORs), hazard ratios (HRs) with 95% confidence intervals (CIs), and original raw incidences from studies comparing fracture rates in anaemic versus non-anaemic patients were extracted and pooled with the random-effects model. I2 test was used to assess heterogeneity. Risk of bias assessment was performed using the Quality of Prognostic Studies tool. PROSPERO: CRD42021241109. Results: A total of 13 studies were identified; 8 of them were included in the quantitative synthesis. Anaemia was found to be a risk factor for fracture compared to non-anaemia. Anaemia increased hip fracture risk in both older men (HR = 1.71; CI: 1.46–2.00, pI2 = 83.2%) and women (HR = 1.31; CI: 1.13–1.52, ppI2 = 61.1%). Anaemia was also associated with increased vertebral (HR = 1.21; CI: 1.04–1.40, p = 0.012) and all-type (HR = 1.49; CI: 1.19–1.86, pConclusion: Our results suggest that there is a significant relationship between anaemia and fracture risk in older adults. This association is stronger among older men than women and differs in the different types of fractures.