Mean platelet volume/platelet count ratio in anemia

Iron deficiency anemia (IDA) is the most prevalent micronutrient deficiency in the world, and the leading cause of anemia [1, 2]. IDA is due to a defect in hemoglobin (Hb) synthesis that results in microcytic red blood cells (RBC) and decreased amount of Hb [3]. In addition to changes in RBC indices, IDA is also known to cause mild to moderate thrombocytosis. While reactive thrombocytosis soon resolves after iron supplement, previous studies have suggested that thrombosis in IDA may occasionally results in clinical manifestation such as thrombotic events [4]. Although increased endogenous erythropoietin may play a role in thrombocytosis, mechanism of platelet production in irondeficiency induced thrombocytosis is yet to be fully understood and relevant platelet indices are not fully evaluated [5]. Recently, mean platelet volume (MPV) has been suggested as a useful platelet index for platelet function and activation [5–10]. Also, MPV/platelet count ratio has been proposed as a new parameter for the prediction of long-term mortality in patients with myocardial infarction [9]. In this context, we planned to investigate MPV and MPV/platelet count ratio according to serum iron status in patients with anemia. The study group included 330 specimens of which Hb levels were below 11.0 g/dL from patients group at Kyung Hee University Hospital, a tertiary teaching hospital, between January and December 2011. Because the standard biochemical markers of iron metabolism have been traditionally serum or plasma iron, total iron binding capacity (TIBC), and transferrin saturation (TfS), patients group was defined as shown in Figure 1. For the control group, 311 subjects for medical check-ups were enrolled from the same hospital, which had been used as control group in our previous reports [11, 12]. Mean age of patients group was 52.75, and male to female ratio was 153 : 177. Blood sample was obtained through venepuncture into ethylenediaminetetraacetic acid (EDTA)containing tubes and complete blood count (CBC) parameters were measured using Advia 2120 (Siemens Healthcare Diagnostics Inc., Tarrytown, NY, USA) within 2 hours. Serum iron and unbound-iron binding capacity was measured in Toshiba chemical analyzer (Toshiba, Nasushiobara, Japan), from which TIBC and TfS was calculated. ANOVA followed by post-hoc analysis were used to compare means and receiver operating characteristic (ROC) curve analysis was done to evaluate the diagnostic performance. A value of p< 0.05 was considered statistically significant. These statistical analyses were performed with MedCalc v11.6 (MedCalc Software, Mariakerke, Belgium) and Excel 2007 (Microsoft Corporation, Redmond, WA, USA). Mean of platelet count, MPV levels and MPV/platelet count ratio were significantly different among three groups, respectively. Platelet count was markedly increased in IDA patients group (mean 335.78 10/L) compared to a significantly lower level in non-IDA-anemia patients group (mean 198.71 10/L, p< 0.001). MPV displayed statistically significant differences in all three groups (Figure 2a). It was significantly higher in patients group of anemia other than IDA (mean 8.60 fL) than other two groups (mean of control group 8.02 fL, mean of IDA patients group 8.34 fL, respectively, p< 0.001) broadening the difference of MPV/ platelet count ratio between groups which showed to be more