Diabetes Mellitus (DM) is common in lung transplant recipients and is a major risk factor for mortality. We undertook a prospective study to determine whether glycaemic control was associated with survival following lung transplantation (LTx). We collated all available fasting and random glucose and HbA1c results of the 195 consecutive patients who underwent LTx from 1/8/2010 – 1/8/2013. Patients were followed until 15/5/2015. Eighty-six patients with DM (pre-and post-LTx or new onset DM post-LTx) were included in analyses to avoid bias. Cox regression analyses were performed to determine the effect of glycaemic control on survival.
Patients had a mean of 1.3, 57.7 and 1.5 fasting glucose, random glucose and HbA1c tests in the first 3 months after LTx and a mean of 5.5, 21.4 and 5.6 tests throughout follow up. Of the 86 patients with DM, 28 (33%) died. Estimated mean survival in these patients was 3.6 (95%CI 3.3 – 4.4) years.
Mean glucose and HbA1c over the first 3 months following LTx were not associated with survival. However random glucose from 3 months until end of follow up was associated with reduced survival HR 1.31 (95% CI 1.13 – 1.52, p<0.001). Fasting glucose and HbA1c from 3 months until end of follow up were not associated with survival, although the sample size and relatively small number of tests performed may have influenced this result.
Our findings suggest that glycaemic control in the first 3 months following LTx is not associated with survival. However the 31% increase in mortality risk for each 1mM increase in mean random glucose over the longer term is significant. Tighter glycaemic control following lung transplantation may result in improved survival.