Use of Lispro Insulin Reduces Nocturnal Hypoglycemia
The danger of hypoglycemia, while ever present, is greater at night while people are sleeping. Many people do not awaken when low, and severe hypoglycemia in young children is thought to cause memory impairment. For everyone who worries about nocturnal hypoglycemia, a recent study offers some good news: use of lispro insulin (Humalog) reduces the risk of hypoglycemia at night, at least in adults.
The U.K. study included 165 adults with Type 1 diabetes who used a basal bolus regimen, in which participants injected short-acting insulin (either Regular or Humalog) before each meal and long acting NPH before bed. Participants spent two months in a pre-study run-in period, then spent four months using either Humalog and NPH or Regular and NPH, then switched to the other regimen. The study tracked the number of hypoglycemic episodes, both mild (individuals could help themselves) and severe (outside help was needed).
During period 1, there were 8 periods of severe hypoglycemia in two patients using Humalog and 12 episodes of severe hypoglycemia in six patients using Regular. This is not statistically different. However, there was a three-fold reduction in nocturnal hypoglycemia (12:00 to 6:00 a.m.): 181 episodes among patients using Regular, but only 52 in patients using Humalog (p = 0.001).
From Effect of the Fast-Acting Insulin Analog Lispro on the Risk of Nocturnal Hypoglycemia During Intensified Insulin Therapy (Diabetes Care 22:1607-1611, 1999).