Secondly, hypertension often coexists with subclinical renal impairment—even before overt chronic kidney disease develops, hypertensive patients may have decreased renal erythropoietin production.[40–43] This blunted erythropoietin response leads to an anemia of chronic disease, as evidenced by studies finding hypertensives with reduced glomerular filtration (eGFR < 90 ml/min) are nearly 3 times as likely to have anemia due to inadequate erythropoiesis. Here, EPO is linked to anemia (phenotype).