Collecting and handling of specimens
Venous blood sample was taken from all participants following an overnight fasting (12–14 h). Sera recovered from clotted samples following centrifugation at 800 g at room temperature were aliquoted in several fresh microtubes. One aliquot was used for serum glucose and lipid profile determination on the same day of sampling whereas the other microtubes were kept at −80° C until the day of analysis.