Prognostic Factors for Mental Retardation in Patients with Tuberous Sclerosis Complex

Purpose: To analyze the prognostic factors for mental retardation in patients with tuberous sclerosis complex (TSC). Methods: We retrospectively reviewed 35 in-patients with TSC in a medical center and analyzed the clinical features. 19 of 32 patients (59.4%) fulfilled the classical diagnosis of tuberous sclerosis. According to the diagnostic criteria of Roach et al., 30 patients had definite TSC and 5 patients possible TSC. Results: Among the 35 patients, the mean age at diagnosis was 15.9 ± 12.5 years, and the male-to-female ratio was 14:21. 11 of 30 patients (36.6%) had a family history of TSC. The most frequent CNS manifestations were seizures (32/35, 91.4%) and mental abnormality (12/32, 62.5%). The most common cutaneous manifestation was facial angiofibroma (27/35, 77.1%) and the most common seizure pattern was generalized tonic clonic seizures (22/32, 62.9%). Poor control of seizures (p=0.006) and the presence of cortical tubercles in imaging studies (p=0.03) were correlated statistically with mental abnormality. Poor control of seizures (15/32, 46%) was more common in generalized tonic clonic seizures than other seizure types (p=0.041). Twenty-six of 28 patients (92.8%) displayed the typical findings of cortical tubers and subependymal nodules on the brain CT or MRI. Conclusion: Mental retardation in TSC was correlated with poor control of seizures and the presence of CNS lesions.