Correlation of whole blood viscosity and HbA1c with age in diabetes patients: implications for diabetes research and management in low-mid income countries

Abstract

Background: There is a concept of association between whole blood viscosity (WBV) and glycated hemoglobin (HbA1 c), but the odds that both biomarkers increase with age are yet to be exhaustively investigated. The aim of this Health records-based study was to determine the correlation of age with HbA1c as well as age and WBV in diabetes patients. Methods: The setting of this work was a medical General Practice in a regional Australia. Deidentified pathology data of diabetes patients, which included HbA1c, routine biochemistry and hematology results were mined. WBV was derived from hematocrit and serum total protein levels. Statistical analyses included comparison of biomarkers between stratified aged-groups, the correlations with age, and the odds ratio of the variables to increase with age. Results: Age showed a weak negative correlation with HbA1c (r = -0.25), there were odds that HbA1c can increase by 1% in 2-years (p<0.04). There was weak positive correlation of WBV with age in oldest aged-group (r = 0.27), but a confounding effect of anemia causing the odds to decrease 1 % in 3-years. HbA 1 c and WBV were moderately positively correlated in patients with good glycemic control (r = 0.39). Conclusion: The notion that HbA1c and WBV increase with age requires rethinking, especially for individuals living with diabetes and undergoing treatment. Implications for interpreting the results of these two tests in diabetes research and clinical management is discussed in the context of limitations in low- and middle-income countries.