57676ournal ofNeurology, Neurosurgery, and Psychiatry 1996;60:576-578 SHORT REPORT J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.60.5.576 on 1 May 1996. Downloaded from A comparison of idiopathic hypersomnia and narcolepsy-cataplexy using self report measures and sleep diary data Dorothy Bruck, J D Parkes Abstract Published data comparing patients with IH Eighteen patients with idiopathic hyper- and patients with NLS outside the sleep labo- somnia (IH) were compared with 50 ratory are scarce. Using self report question- patients with the narcoleptic syndrome of naires and sleep diary data our aim was to cataplexy and daytime sleepiness (NLS) determine the extent of group differences and using self report questionnaires and a which variables best discriminated between IH diary of sleep/wake patterns. The IH and NLS. group reported more consolidated noc- turnal sleep, a lower propensity to nap, greater refreshment after naps, and a Patients and methods greater improvement in excessive day- DIAGNOSTIC CRITERIA time sleepiness since onset than the NLS Idiopathic hypersomnia group. In IH, the onset of excessive day- Patients were selected with a complaint of time sleepiness was predominantly asso- excessive daytime sleepiness without cataplexy ciated with familial inheritance or a viral and with no evidence of any medical, psycho- illness. Two variables-number of logical, drug related, or respiratory disorder. reported awakenings during nocturnal All patients met diagnostic criteria ascertained sleep and the reported change in sleepi- from questionnaire responses: Epworth sleepi- ness since onset-provided maximum ness scale score8 > 13; duration of excessive discrimination between the IH and NLS daytime sleepiness > five years, profile of groups. Confusional arousals, extended mood states depression-dejection scale score nap or nocturnal sleep, autonomic ner- within one SD of outpatient norms,9 no cata- vous system dysfunction, low ratings of plexy,'0 no clinical evidence of sleep apnoea or medication effectiveness, or side effects of upper airway resistance syndrome, neck cir- medication were not associated differen- cumference < 16-5 inches, snoring amount tially with either IH or NLS. and volume moderate level or less, no sugges- http://jnnp.bmj.com/ tion of chronic insomnia, no excessive alcohol (7 Neurol Neurosurg Psychiatry 1996;60:576-578) intake, no other medical condition that may contribute to excessive daytime sleepiness, and no head injury within 12 months of onset of Keywords: idiopathic hypersomnia; narcolepsy; exces- excessive daytime sleepiness. In addition, all sive daytime sleepiness patients with IH met minimal and additional criteria of the International Classification of on October 4, 2021 by guest. Protected copyright. Idiopathic hypersomnia (IH) has been distin- Sleep Disorders (ICSD) for IH.4 guished from narcolepsy on the basis of the presence of prolonged rather than short diur- NARCOLEPTIC SYNDROME nal sleep periods and the absence of both cata- All patients with NLS met the minimal ICSD Department of plexy and episodes of rapid eye movement at criteria4 for narcolepsy and had unequivocal Psychology, Victoria the onset of sleep. Several studies have associ- cataplexy as established through both clinical University, St Albans, PO Box 14428, MCMC ated IH with longer nocturnal and nap sleep, interview and their score on the postural ato- Melbourne 8001, less refreshing naps, more confusional nia rating scale.'0 Australia arousals, and deeper sleep with fewer awaken- D Bruck ings than in the narcoleptic syndrome RESPONSE RATE AND PATIENTS Department of (NLS).14 Stimulant medication may be less Idiopathic hypersomnia Neurology, Institute of Psychiatry, De effective and poorly tolerated by patients with The questionnaires (see later) were circulated Crespigny Park, 6 to 209 patients who had attended the sleep Denmark Hill, London Three clinical variants of IH have been clinic at the Maudsley Hospital, London over SE5 8A, UK described. Familial of excessive a of 10 and whose J D Parkes 7(1) history period years primary diag- Correspondence to: daytime sleepiness with symptoms suggesting nosis was hypersomnia of unknown origin. Dr Bruck. autonomic nervous system instability. (2) Sixty three returns were obtained and 42 Received 8 September 1995 Postinfective onset (commonly infectious patients returned evaluable questionnaires. and in revised form 5 January 1996 mononucleosis). (3) No familial or postinfec- Twenty four of these were excluded as their Accepted 12 January 1996 tive history. responses were outside the defined criteria. A comparison ofidiopathic hypersomnia and narcolepsy-cataplexy using self report measures and sleep diary data 577 Table 1 Mean (SD) ratings by patients with IH and patients with NLS (n = 50) sible. (3) Profile of mood states8 checklist to be IH NLS completed after breakfast. J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.60.5.576 on 1 May 1996. Downloaded from (n = 18) (n = 50) Confusion on awakening DATA ANALYSIS 1-5: never-always 27 (1 1) 2 9 (0 9) Student's t tests, X2 analyses, and logistical dis- Confusion from night sleep 1-5: never-always 2 1 (09) 2-3 (1-0) criminant analysis were used as appropriate. Refreshed from naps Sleep diaries that indicated stimulant use were 1-5: never-always 2-5 (1-2) 3 2 (11)* excluded and the sleepiest day was chosen for Refreshed in morning 1-5: never-always 2-8 (1-2) 2 9 (1-2) analysis. Sleepiness five years ago 1-5: lot worse-lot better 3-4 (1-2) 29 (11) Sleepiness at onset Results 1-5: lot worse-lot better 3-5 (1 6) 2 7 (1-7)* Medication effectiveness EXCESSIVE DAYTIME SLEEPINESS ONSET, 1-5: not at all-extremely 3-2 (1 1) 3-8 (1-1) DURATION, AND SEVERITY Medication side effects The IH and NLS groups were similar in terms 1-5: not at all-extreme 2-5 (1-6) 2 3 (1-3) Arousal threshold during sleep of reported duration of excessive daytime 0-100: easy-hard to wake 60-0 (29 5) 53-2 (30-1) sleepiness (23-4 and 29 years) and age of onset Epworth sleepiness score of excessive daytime sleepiness (22-3 and 23- 1 0-24: no propensity-very high 187 (31) 20-3 (2.7)* Estimated TV nap duration years). The propensity to fall asleep (Epworth) (minutes) 50 9 (67-8) 31-0 (44 3) was slightly lower in the IH group than the Estimated afternoon nap duration NLS group (t(66) = 2 1, P = 0 04). Patients (minutes) 75-8 (54 5) 65-4 (45 4) with IH a in Body weight reported slight improvement (pounds) 156-8 (28-6) 177 8 (32 0)* severity of excessive daytime sleepiness after Insomnia score onset, whereas patients with NLS reported a 0-100: like "a log"-severe 37-6 (38 9) 47.7 (30 4) slight deterioration (t (63) = 2-4, P = 0-017). *P < 0 05; t test. 1-5, 0-100, 0-24 indicate intervals on response scale. Table 1 shows all questionnaire mean values. Those reporting a first degree relative with The final IH sample (eight male, 10 female) excessive daytime sleepiness were in the had an average age of 45-61 (SD 17-06, range minority (0-38 IH; 024 NLS). No familial 18-70) years. member with sleep paralysis or NLS was reported by the IH group, but such members Narcoleptic syndrome were present in the NLS group (O*25 and 0 10 The questionnaires were circulated to 132 respectively). Glandular fever (or an illness of patients with NLS from the same clinic who similar symptoms) in the six month period to had previously participated in a questionnaire onset of excessive daytime sleepiness was study. Fifty eight questionnaires were returned reported more often by the IH group (031) complete and 50 patients aged 70 or less were than the NLS group (0-16). There was no included to obtain an age matched sample. overlap between the six patients with IH who The NLS sample (24 male, 26 female) had a reported such an illness before the onset of mean age of 52 18 (SD 15 12, range 15-70) excessive daytime sleepiness and the six years. patients with IH reporting familial excessive daytime sleepiness. QUESTIONNAIRES http://jnnp.bmj.com/ The questionnaires consisted of three parts. DAYTIME SLEEP-WAKE BEHAVIOUR (1) A five page questionnaire required Patients with IH were less likely to feel responses on a five point scale (100 mm line) refreshed after a nap than patients with NLS (t or a yes/no answer. (2) The sleep diary about (63) = 2-22, P = 003). Confusion on waking sleep, medication, and alcohol intake com- from naps or night sleep did not differ between pleted for three consecutive days. Stimulant groups; nor did the extent of refreshment felt medication was to be avoided as much as pos- in the morning. Half of each group said they were most alert in the morning (056 IH; 0A48 on October 4, 2021 by guest. Protected copyright. NLS). The average duration of each nap was Table 2 Mean (SD) and range for sleep diary variables comparing patients with IH and similar in both groups (see tables 1 and 2). patients with NLS (all stimulantfree) IH NLS NOCTURNAL SLEEP-WAKE BEHAVIOUR (n = 13) (n = 23) The sleep diary (table 2) showed that noctur- Number of naps 2-4 (1 2) 3-4 (1-7) nal sleep in the IH group was characterised by 0-4 0-8 significantly fewer awakenings (t (40) = 3 7, P Total nap time (min) 70 7 (61-8) 113-1 (91 3) 0-240 30-420 = 0-001) and reduced wake duration (t (40) Average nap duration (min) 36-6 (32 7) 37-3 (26 6) = 2 2, P = 0 015) than in the NLS group. 5-120 10-105 Nocturnal sleep latency (min) 15 2 (12-3) 11-8 (13-1) Other nocturnal sleep variables did not differ 1-45 1-40 between groups.