Relationship between diabetes control and pulmonary function in insulin-dependent diabetes mellitus

purpose: To evaluate the effect of different levels of glycemic control on the pulmonary function of subjects with type I insulin-dependent diabetes mellitus. patients and methods: Eighteen subjects with type I insulin-dependent diabetes mellitus with no history or physical findings of respiratory disease. Patients were given insulin therapy with a standard twice-daily insulin injection regimen (standard treatment group) or a subcutaneous insulin infusion device (insulin pump) (intensive treatment group). Glycosylated hemoglobin (HbA_1c) levels were determined at quarterly intervals in both groups of patients (standard treatment group, n = 10; intensive treatment group, n = 8). Pulmonary function and diffusing capacity for carbon monoxide (DL_CO) were measured after 6 years of continuous follow-up. results: The average HbA_1c in the standard treatment group was significantly higher than that of the intensive treatment group throughout the 6 years of follow-up (p <0.001). The forced vital capacity of the standard treatment group was 85 ± 3% of predicted as compared with 106 ± 4% of predicted in the intensive treatment group (p <0.001). The DL_CO was also significantly diminished in the standard treatment group as compared with that in the intensive treatment group (65 ± 2% versus 87 ± 4% of predicted) (p <0.001). conclusion: These data confirm previous reports of abnormal respiratory function in subjects with insulin-dependent diabetes mellitus and suggest that long-term near-normoglycemia may be beneficial in preventing the deterioration of pulmonary function associated with diabetes mellitus.