OBJECTIVES:

To determine the risk of diabetes mellitus (DM) in patients with myasthenia gravis (MG) in a large cohort representing 99% of the Taiwan population.

METHODS:

Data from the Taiwan National Health Insurance Database were used to conduct retrospective cohort analyses. The study cohort comprised 1520 patients with MG who were four-fold frequency matched to those without MG by age and sex, and assigned the same index year. Cox proportional hazard regression analysis was conducted to estimate the risk of DM.

RESULTS:

The MG cohort had a 1.26-fold increased risk of developing DM compared with the comparison cohort (HR=1.26, 95% CI=1.04-1.53). MG patients without corticosteroids use had no increased risk of developing DM (HR=1.05, 95% CI=0.79-1.40), and MG patients with corticosteroids use had a 1.46-fold increased risk of developing DM (HR=1.46, 95%=1.15-1.86). In addition, patients with MG received aggressive treatment, associated thyroid diseases, and male patients had higher risk of DM.

CONCLUSION:

This population-based retrospective cohort study demonstrates that MG is associated with a high risk of DM, which might be related to the adverse effect of corticosteroid and aggressive therapy.