Prognostic factors for mental retardation in patients with tuberous sclerosis complex

To analyze the prognostic factors for mental retardation in patients with tuberous sclerosis complex (TSC).

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.

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.

Mental retardation in TSC was correlated with poor control of seizures and the presence of CNS lesions.