Age and Gender Differences in Blood Viscosity: Clinical Laboratory Insights for Diabetes Management

Introduction: Blood viscosity is elevated in diabetes and is inversely related to blood flow. The pathology evidence base associated with blood stasis, namely hematocrit and serum total protein levels, is negatively correlated with age, but affordable pathology tests for blood stasis remain underutilized in clinical medicine practice. This study is intended to evaluate changes in estimated whole blood viscosity (eWBV) with age and gender, as an index of blood stasis and its associated indices of hematocrit and serum total protein levels. Method: This was a clinical laboratory observational retrospective study involving 10 years of pathology data. Three clinical medicine parameters, including eWBV, hematocrit and proteinemia, were compared in stratified age groups. Data were those monitored for HbA1c (N = 21,021). Statistical analysis included univariate (ANOVA) and multivariate (MANOVA) as well as correlation. Results: Average levels of proteinemia, hematocrit and eWBV were different in stratified age groups, and lower in females compared to males. MANOVA analysis shows a significant difference in the three clinical medicine parameters between the younger adults and the elderly (p < 0.001). Age and eWBV are inversely correlated, but this may be negligible with diabetes (r = −0.17). Discussion: There are age-related and gender differences in the pathology evidence base that underpins blood viscosity. The implication of lower blood viscosity in women and the elderly is a higher risk of bleeding. The potentially higher risk of bleeding with increasing age is contrary to the concern for thrombosis, which means that antiplatelet prophylaxis among the elderly may be confounded.