Diabetes mellitus (DM) is common in lung transplant (LTx) recipients and is associated with increased mortality. We conducted an observational study of all patients receiving LTx between 1/8/2010-1/4/2013 inclusive to determine current management of DM and insulin requirements over time. DM status was determined by oral glucose tolerance test performed pre-, 3 months, then annually after LTx. DM management was determined from medical records.
Of 174 patients in total, 37 (21%) had DM before and after LTx, and 40 (23%) developed DM post-transplant, which persisted throughout follow-up. A further 18 (10%) had transient DM, which subsequently resolved. Of those with diabetes both pre- and post-LTx, 19 (51%) used insulin pre-transplant. By 3 months, 33 (92%) required insulin and 24 of the surviving 28 (86%) remained on insulin at 2 years. In patients taking insulin pre-LTx, there was no significant change in mean insulin dose from pre- to 3 months post-LTx (34 (SD 21)–44 (19) units, p=0.12), even when adjusted for weight. There was also no difference in insulin dose between 3 months and 2 years, despite a significant fall in prednisolone dose over this time.
Most patients with new onset DM (32/40, 80%) were diagnosed by 3 months and 27/32 (84%) were on insulin at this time. Overall, 31/40 (78%) patients with new-onset diabetes required insulin. Two patients were managed solely with oral hypoglycaemic agents. Seven patients (18%) had dietary management.
Of the 18 patients with transient DM, 6 were treated with insulin. The remainder were diet controlled. Insulin was commenced by 3 months in all 6 patients at a mean dose of 15 units (0.22 units/kg) per day.
Insulin is the mainstay of DM management following LTx. There was no significant change in insulin dose before and after LTx despite changes in prednisolone dose and clinical status.