Fasting plasma glucose and glycosylated haemoglobin levels in the assessment of diabetic control in non-insulin-dependent diabetes in the young

Response to diet and drug therapy was assessed in a group of 85 Indian patients with non-insulin-dependent diabetes in the young (NIDDY). There was a significant decrease in fasting plasma glucose (FPG) values on therapy (pretreatment 13.3 ± 0.5 mmol/l; post-treatment 9.7 ± 0.4 mmol/l) (P<0.001). Prior to therapy the majority of patients had either moderate (40%) or severe (59%) diabetes; on therapy, the majority had either mild (21%) or moderate (62%) diabetes. Estimation of glycosylated haemoglobin (Hb A₁) levels revealed that control was excellent (Hb A₁<10%) in 47% of patients and excellent or adequate (Hb A₁≤12%) in 78%. Hb A₁ levels correlated significantly with the FPG value (r = 0.78; P<0.001). In 8 patients with iron deficiency anaemia the Hb A₁ level did not fall within the correlation norms between Hb A₁ and FPG. Treatment of the anaemia restored the correlative norms. Hb A₁ levels were significantly higher in patients with microvascular complications (12.1 ± 0.8%) than in those without any vascular complications (10.3 ± 0.3%) (P<0.01).