Association of hematological parameters with insulin resistance, insulin sensitivity, and asymptomatic cerebrovascular damage: the J-SHIP and Toon Health Study

Yasuharu Tabara, Michiya Igase, Isao Saito, Wataru Nishida, Katsuhiko Kohara, Susumu Sakurai, Ryoichi Kawamura, Yoko Okada, Shinichi Hitsumoto, Hiroshi Onuma, Tokihisa Nagai, Yasunori Takata (+7 others)
2013 Clinical Hemorheology and Microcirculation  
Elevated hematocrit levels have been suggested to be an independent determinant of insulin resistance and type 2 diabetes. To clarify the diagnostic significance of hematocrit level, we investigated the association with hemodynamic profiles, insulin resistance and insulin sensitivity, arterial properties, and asymptomatic cerebrovascular damage in a general Japanese population. This study included 1,978 participants from two independent cohorts. Insulin sensitivity was assessed by the oral 75 g
more » ... ed by the oral 75 g glucose tolerance test. Carotid ultrasonography was performed to evaluate atherosclerosis and wall shear stress. Periventricular hyperintensity and lacunar infarction were assessed by brain magnetic resonance imaging. Hematocrit quartile showed a stepwise association with insulin sensitivity (Q1: 2.2±0.7, Q2: 2.0±0.7, Q3: 1.9±0.7, Q4: 1.8±0.6, p<0.001) and insulin resistance (1.0±0.6, 1.2±0.7, 1.3±0.8, 1.5±1.0, p<0.001). Multiple linear regression analysis adjusted for possible covariates identified hematocrit as an independent determinant of insulin sensitivity (β=-0.074, p=0.019) and insulin resistance (β=0.115, p<0.001). However, this association was lost after further adjustment for visceral fat area and plasma alanine aminotransferase level. Further, no significant association was observed between hematocrit and carotid intima-media thickness (p=0.306) where as wall shear stress was inversely associated with the carotid atherosclerosis (r=-0.250, p<0.001). In contrast, a low hematocrit level was independently associated with periventricular hyperintensity (odds ratio 0.87 (95% CI 0.80-0.95), p=0.001). Hematocrit was positively associated with insulin resistance and insulin sensitivity. This association was epiphenomenon of visceral and hepatic adiposity. Conversely, low hematocrit was a significant risk factor for periventricular hyperintensity independent of insulin resistance.
doi:10.3233/ch-2012-1634 pmid:23109550 fatcat:6yuzxho7xngqpbesopq5qhjevm