Diabetes in Individuals With Tuberous Sclerosis Complex Treated With mTOR Inhibitors

Tuberous sclerosis complex (TSC) is a genetic disorder that is manifested in multiple body systems. A mammalian target of rapamycin (mTOR) inhibitor (mTORi), either everolimus or sirolimus, is now routinely prescribed for multiple clinical manifestations of TSC, including subependymal giant cell astrocytoma and epilepsy. These medications are generally well tolerated. Side effects previously identified in well-designed clinical trials tend to be mild and readily manageable. Regulatory approvals for the treatment of TSC have expanded the use of everolimus and sirolimus clinically, enlarging clinician experience and enabling identification of potential treatment-related effects that are rarer than could be identified or recognized in previous clinical trials.

The medical records of clinical patients from our TSC center who were treated with an mTORi and later developed diabetes mellitus (DM) were analyzed and compared with those who were not treated with an mTORi. Eight individuals received detailed analysis, including laboratory results, concomitant medications, and body mass indices.

Among the 1576 individuals with TSC, 4% taking an mTORi developed diabetes compared with 0.6% of those not on mTORi, showing a significant interaction between DM and mTORi (chi-square = 18.1, P < 0.001). Details of eight patients who developed DM were presented.

The long-term use of mTORi agents in TSC may contribute to a risk of diabetes. Early detection can be critical in management. Additional studies are need to further investigate a causal relationship, but clinicians should be aware of this possible association when initiating and monitoring ongoing treatment.