Changes in Lung Function with Inhaled Insulin

In previous short-term studies, inhaled insulin caused small declines in lung function. In this industry-sponsored trial, researchers assessed longer-term respiratory effects of inhaled insulin.

Nearly 600 adults with type 1 diabetes were randomized to receive premeal inhaled insulin (Exubera) or premeal subcutaneous short-acting insulin; both groups also received long-acting basal insulin. At 3 months, mean FEV₁ had declined by 0.05 liters in the inhaled insulin group and 0.03 liters in the subcutaneous insulin group, a small but statistically significant difference. However, after 3 months (and through 24 months), FEV₁ declined at the same rate in both groups. For diffusing capacity, the same pattern was noted — a small initial decline, bu…