Haematocrit and risk of development of Type 2 diabetes mellitus in middle‐aged Japanese men

Abstract

These results indicate that haematocrit contributes to the risk of developing Type 2 diabetes.

Hematological Parameters and Prediabetes and Diabetes in Adults from the General Population: A Cross-Sectional Study

“…In this context, one's attention was particularly turned on lifestyle risk factors, inflammatory parameters, metabolic abnormalities, and genetic risk factors, many of which have been found to be independently associated with type 2 diabetes [2]. Among those risk factors, routinely measured hematological parameters, such as White Blood Cell (WBC) count and hematocrit (HCT) level were associated with insulin resistance and incident type 2 diabetes [3][4][5][6][7][8]. Hematocrit is positively correlated with hyperinsulinemia and risk factors associated with insulin resistance, e.g.…”

“…Furthermore, hematocrit is a major determinant of blood viscosity. Increased blood viscosity also contributes to the development of insulin resistance [3][4][5][6][7][8]. In addition, chronic inflammation is involved in the pathogenesis of type 2 diabetes and evidence from epidemiological studies suggests an association between total WBC or leukocyte count, a non-specific marker of inflammation, and diabetes risk [2].…”

Elevated 1-h post-challenge plasma glucose levels in subjects with normal glucose tolerance or impaired glucose tolerance are associated with whole blood viscosity

“…Notably, our data suggest that, even within the normal glucose tolerance category, individuals having 1-h post-challenge plasma glucose [155 mg/dl exhibit an increase in whole blood viscosity comparable with that observed in subjects with IGT. Significant associations of selected hemorheological parameters, mainly hematocrit, with future type 2 diabetes have been observed in previous clinical studies [21][22][23][24][25]. Elevated blood viscosity has been also observed in subjects with high-normal fasting glucose and IFG [6,27].…”

“…1-h plasma glucose levels have been found to be predictive of the risk of myocardial infarction and coronary heart disease [44] in subjects affected by type 2 diabetes and total mortality in nondiabetic population [45]. Elevated blood viscosity may represent one of the physio-pathologic mechanisms underlying the link of 1-h hyperglycemia to both type 2 diabetes [20][21][22][23][24][25][28][29][30] and cardiovascular diseases [7-15, 35-37, 44, 45]. Since IGT and IFG have already been recognised as dysglycemic conditions which require specific attention to halt the progression toward type 2 diabetes and decrease the associated cardiovascular risk, employing the 1-h OGTT plasma glucose criterion to screen NGT individuals may be useful to identify a subgroup that would otherwise be regarded as normal who may benefit from life style modifications and/or pharmacologic intervention in order to avoid or slow adverse clinical outcomes.…”

“…Indeed, several crosssectional studies have shown a connection between increased blood viscosity, impaired insulin sensitivity, and type 2 diabetes [16][17][18][19][20]. More importantly, longitudinal studies have demonstrated that hematocrit, a crucial parameter of blood viscosity, and blood viscosity itself are associated with incident type 2 diabetes [21][22][23][24][25]. These evidences suggest that elevated blood viscosity may occur early in the natural history of type 2 diabetes, but only limited data are available, since the studies carried out on subjects with normal glucose tolerance (NGT) or impaired glucose homeostasis were of small size or employed suboptimal definitions of dysglycemic states such as impaired glucose tolerance (IGT) [6,26,27].…”