Significant results were observed already at the early stages of anemia (for nadir Hb 11.0–11.5 g/dL and the risk of cerebral infarcts [odds ratio (OR) 2.13, 95% CI 1.04–4.34, p = 0.04, I2 = 65%] and poor long-term outcome [OR 3.30, 95% CI 2.55–4.28, p < 0.0001, I2 = 0%]). This evidence concerns the gene GSTM1 and anemia (phenotype).