ELSEVIER Brain & Development 1995; 17:52-6
Original article
Sleep disorders in tuberous sclerosis: a polysomnographic study
Oliviero Bruni *, Flavia Cortesi, Flavia Giannotti, Paolo Curatolo
Department of Child Neurology and Psychiatry, Universityof Rome 'La Sapienza', Via dei SabeUi 108, 00185 Rome, Italy
Received 6 June 1994; accepted 27 October 1994
Overnight polysomnography was performed in 10 subjects with tuberous sclerosis (TS) and partial epilepsy in
order to investigate the relationships between sleep organization, sleep disorders and epilepsy. Sleep architecture
abnormalities were observed in 9 cases. Compared with ten healthy age-matched controls, the TS group showed a
shorter total sleep time, a reduced sleep efficiency, a higher number, of awakenings and stage transitions, an
increased wake after sleep onset and stage 1 and a decreased ItEM sleep. Children with seizures showed a more
disrupted sleep architecture compared with seizure-free children. Sleep disorders in TS were mainly due to
sleep-related epileptic events and were more evident in children who showed large bifrontal or temporal tubers on
MRI.
Keywords: Tuberous sclerosis; Sleep disorder; Polysomnography; Epilepsy
1. INTRODUCTION
Sleep disorders, such as night wakings, waking early,
seizure-related sleep problems, and excessive daytime sleepi-
ness, are considered one of the most common behavioral
manifestations in children with tuberous sclerosis (TS) [1,2].
In a study on 300 children investigated by postal question-
naire, Hunt [3] reported the presence of sleep problems in
58% of children and seizure-related sleep problems in 41%.
In a polysomnographic (PSG) study performed on two
cases with TS, both having subependymal nodules of caudate
nucleus, Nezu et al. [4] demonstrated a synaptic supersensi-
tivity of the dopamine receptor that seems to play a role in
the pathophysiology of epilepsy. However, in this study sleep
organization was not investigated.
Since no detailed studies were available in the literature,
we performed PSG in children with TS to better investigate
the relationships between sleep organization, sleep disorders
and epilepsy.
2. MATERIALS AND METHODS
Ten children (9 females and 1 male, aged 2-17.1 years,
mean age 11 years), referred to the Department of Child
* Corresponding author. Fax: (39) (6) 495 7857.
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Neurology and Psychiatry of the University of Rome 'La
Sapienza', with a diagnosis of TS confirmed by clinical and
MRI findings, were studied. All the patients had partial
epilepsy and were on anti-epileptic therapy. Intellectual or
developmental quotients (IQ, DQ) were evaluated by means
of standardized psychometric examinations (Wechsler Scale:
WPPSI or WlSC-R, Stanford-Binet and Brunet-L6zine) ac-
cording to their age and mental level. Patients were classified
as follows: normal intelligence (DQ or IQ > 85), borderline
(DQ or IQ 70-85), mild and moderate mental retardation
((DQ or IQ 40-70), severe mental retardation (DQ or IQ <
40). Clinical, EEG and neuroimaging data are shown on
Table 1.
Two consecutive overnight PSG using Nicolet Ultrasom, a
sleep/wake analyzer, were recorded in the Sleep Laboratory
of our Department.
Two montages (Fp2-C4, C4-T4, T4-O2, Fpl-C3, C3-T3,
T3-O1 or Fp2-F8, F8-C4, C4-P4, P4-O2, Fpl-F7, F7-C3,
C3-P3, P3-O1, C3-A2, O2-A1, left and right electro-oc-
ulography, chin EMG, EKG, abdominal respiratory effort)
were used according to the main EEG focus to document
epileptiform activity and nocturnal seizures. Gold-plated sur-
face electrodes were applied to the scalp using the collodium
technique according to the International 10-20 System. Sleep
recordings were started at the patients' habitual bedtime
and continued until spontaneous awakening. To avoid the
so-called first night effect we considered only the second
night recordings. Records were visually scored in 30-s epochs
according to the standard criteria of Rechtschaffen and Kales
[5].