GSTM1 and anemia (phenotype): By studying the independent association between Hb levels and the abovementioned domains, we found that, by considering the <12 g/dL cut-off level, age, comorbidities, and gender were independently associated with anemia, while, by considering the <13 g/dL cut-off level, also worse functional capacities (POMA) and nutritional status were independently associated with anemia.