Mortality in Tuberous sclerosis Complex: Current understandings

Background

Tuberous Sclerosis Complex (TSC) is a multisystemic neurocutaneous disorder caused by pathogenic loss of function variants in the tumour suppressor genes TSC1 and TSC2. The resultant hamartomas confer significant medical risks by disruption of local tissues. Risk of mortality in TSC is known to be elevated, but only recently have multiple studies assessed specific causes of mortality in TSC.

Methods

A critical literature review of all available studies examining mortality in TSC was conducted using the terms “TSC”, “Tuberous Sclerosis Complex”, “mortality”, “death”, and “life expectancy”, in PubMed and Google Scholar, until December 15, 2024.

Results

We identified 13 studies that reported a total of 411 deaths from 6735 TSC individuals. Data were typically incomplete and causes of death in many cases were obtained from death certificates. Crude mortality per 100 individuals ranged from 1.4 to 13.8 over average intervals of 11–45 years. Standardized Mortality Ratios or hazard ratios (versus control group) ranged from 3.0 to 4.9 (mean 4.3). Mean life expectancy was 66.2 years compared to an average of 81.8 in the general population. In the seven studies that reported specific causes of mortality in the general TSC population, 6/7 studies (85 %) had renal or central nervous system disease as the most common cause of mortality. Lymphangioleiomyomatosis was also found to confer significant risk of mortality in adult women and cardiac rhabdomyomas were the dominant cause of neonatal mortality. TSC-associated neuropsychiatric disorders-related mortality and morbidity may be underestimated.

Conclusion

Mortality in TSC is elevated compared to the general population, with central nervous system and renal disease most frequently culpable. Further cohort studies will be required to establish and characterize the risk of mortality in TSC in the age of disease-modifying therapies.