Lower HbA1c prolongs hypoglycaemia duration in type 2 diabetics
In type 2 diabetes patients taking sulfonylureas, hypoglycaemia duration is longer at night and is inversely correlated with the level of glycated haemoglobin (HbA1c), a new study reports.
Using a professional-grade continuous glucose monitoring sensor, researchers measured the glucose levels of 300 type 2 diabetes patients (mean age, 69.0±10.7 years; 182 males) who were being treated with sulfonylureas but not insulin. The primary outcome was the duration in hypoglycaemia compared across different categories of HbA1c concentrations, and between night time and daytime.
Participants were categorized according to HbA1c concentrations: ≤6.4 percent, 6.5–6.9 percent, 7.0–7.4 percent, 7.5–7.9 percent and ≥8.0 percent. Hypoglycaemia (glucose <54 mg/dL) duration was longer in the lower categories and decreased progressively as HbA1c levels increased (1.6±2.2, 0.6±2.3, 0.4±1.3, 0.5±1.5 and 0.1±0.2 min/h, respectively).
The difference in duration between the ≤6.4-percent and ≥8.0-percent group was statistically significant (p<0.0125).
The trend remained true even when the threshold for hypoglycaemia was moved to <70 mg/dL. The durations for the corresponding HbA1c categories were 6.8±5.6, 2.6±4.1, 1.8±3.2, 1.6±3.3 and 0.4±0.9 min/h. The difference between the bottom and top categories was significant (p<0.0125).
Moreover, researchers found that among those with HbA1c ≤6.4 percent, 6.5–6.9 percent and 7.0–7.4 percent, hypoglycaemia (glucose <54 mg/dL) duration was significantly longer at night vs day (p<0.05). Duration of hypoglycaemia with glucose <70 mg/dL was also significantly longer during the night across all HbA1c categories.