J Appl Biomed 18:136-142, 2020 | DOI: 10.32725/jab.2020.018

Alterations of glycaemia, insulin resistance and body mass index within the C-peptide optimal range in non-diabetic patients

Vladimír Kron^1,6,*, Miroslav Verner^2,5, Pavel Smetana¹, Jana Janoutová³, Vladimír Janout⁴, Karel Martiník⁶

¹ University of South Bohemia, Faculty of Agriculture, Department of Food Biotechnologies and Agricultural Products Quality, České Budějovice, Czech Republic

² Hospital of České Budějovice, a. s., Central Laboratories, České Budějovice, Czech Republic

³ Palacký University Olomouc, Faculty of Health Sciences, Department of Healthcare Management, Olomouc, Czech Republic

⁴ Palacký University Olomouc, Faculty of Health Sciences, Center for Research and Science, Olomouc, Czech Republic

⁵ University of South Bohemia, Faculty of Health and Social Sciences, Institute of Laboratory Diagnostics, České Budějovice, Czech Republic

⁶ Center for Metabolic Assessment of prof. MUDr. Karel Martiník, DrSc., s.r.o., Hradec Králové, Czech Republic

The study focused on changes or cut-offs of glycaemia, insulin resistance and body mass index within the C-peptide reference range (260-1730 pmol/l). The metabolic profile of individuals in the Czech Republic without diabetes (n = 3186) was classified by whiskers and quartiles of C-peptide into four groups with the following ranges: 290-510 (n = 694), 511-710 (n = 780), 711-950 (n = 720) and 951-1560 pmol/l (n = 673). Fasting levels of glucose, insulin, HOMA IR (Homeostasis Model Assessment for Insulin Resistance) and BMI (body mass index) were compared by a relevant C-peptide range. Participants taking medication to control glycaemia were excluded. The evaluation involved correlations between C-peptides and the above parameters, F-test and t-test. Changes in glucose levels (from 5.3 to 5.6 mmol/l) between the groups were lower in comparison to insulin, which reached relatively greater changes (from 4.0 to 14.2 mIU/l). HOMA IR increased considerably with growing C-peptide concentrations (0.9, 1.5, 2.2 and 3.5) and BMI values showed a similar trend (28.3, 31.0, 33.6 and 37.4). Considerable changes were observed for insulin (5.2 mIU/l, 57.8%) and HOMA IR (1.3, 61.3%) between groups with C-peptide ranges of 711-950 and 951-1560 pmol/l. Although correlations involving C-peptide, insulin, glucose and BMI seemed to be non-significant (up to rxy = 0.25), the mean values of insulin, HOMA IR and BMI showed statistically significant changes between all groups with various C-peptide concentrations (p ≤ 0.001). Generally, most important differences appeared in glucose metabolism and body mass index between C-peptide ranges of 711-950 and 951-1560 pmol/l. Absolute and relative changes of C-peptide concentrations are possible to use for the assessment of glucose regulatory mechanism. The spectrum of investigated parameters could be a useful tool to prevent the risks linked with the alterations of glycaemia.

Keywords: Body mass index; C-peptide; Glucose; Insulin resistance

Grants and funding:

Funding source: This work was supported by Ministry of Agriculture of the Czech Republic NAZV QK1910174.

Conflicts of interest:

The authors have no conflict of interests to declare.

Received: July 17, 2020; Revised: November 22, 2020; Accepted: November 28, 2020; Prepublished online: December 8, 2020; Published: December 14, 2020  Show citation