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, p< 0.001, I2 = 83.2%) and women (HR = 1.31; CI: 1.13-1.52, p< 0.001), but the fracture risk was more increased among men. There was also an increased chance of hip fracture in the presence of anaemia in populations, including both older men and women (OR = 1.64; CI: 1.35-2.01, p< 0.001, I2 = 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, p< 0.001) fracture risk in older men. CONCLUSION: 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.