Hypersomnias Of Central Origin Research Articles

Retrospective cohort study of hypersomnias of central origin from two Australian tertiary sleep disorders services.

Hypersomnias of central origin (HOCO) are diverse in origin and symptomatology and remain poorly described in an Australian population. We hypothesised that the rate of human leukocyte antigen (HLA) DQB1*0602 positivity in the Australian cohort would be comparable to international registries. The current study aims to evaluate epidemiological and clinical characteristics of Australian patients with HOCO, including prevalence of HLA DQB1*0602 positivity, the most specific HLA marker associated with narcolepsy. This is a retrospective study. Patients≥ 16 years of age presenting with symptoms of hypersomnolence who attended one of two Australian sleep centres (New South Wales and Queensland) in the preceding 24 months and had undergone both HLA serology and multiple sleep latency tests (MSLTs) were included. Main outcome measures included demographics, HLA DQB1*0602 positivity, MSLT, and clinical parameters (presence of auxiliary narcolepsy symptoms, laboratory tests, relevant prescribed medications). Eighty-eight patients were included. HLA DQB1*0602 positivity was highest in those with type 1 narcolepsy (NT1) (95.7%) and lowest in those without a classifiable disorder (9.1%). Mean sleep latency was lowest and number of sleep-onset rapid eye movement periods (SOREMPs) highest in the NT1 group. Comorbid disorders, particularly depression and overweight/obesity, were prevalent in all cohorts. Across all diagnostic groups, dexamphetamine was the most commonly prescribed agent for excessive daytime sleepiness. Patients with HOCO assessed in two specialised Australian clinics demonstrate comparable clinical characteristics to other published cohorts internationally; however, available pharmacological agents in Australia do not reflect international standards of care.

Sleep inertia in hypersomnias of central origin: importance of depression and sleep architecture

Sleep inertia in hypersomnias of central origin: importance of depression and sleep architecture

Clinical Approach Hypersomnia of Central Origin and Differential Diagnosis

Clinical Approach Hypersomnia of Central Origin and Differential Diagnosis

Risk of Mental and Sleep Disorders After the Diagnosis of Adrenal Adenomas: A Population-Based Cohort Study

Background: Adrenal adenomas are incidentally diagnosed in 7% of adults undergoing abdominal imaging. Mild autonomous cortisol secretion is present in 50% of adrenal adenomas, and even “nonfunctioning” adrenal adenomas demonstrate abnormal steroid profile. We aimed to 1) investigate the prevalence of mental and sleep disorders in patients with adrenal adenomas and to 2) determine the risk of mental and sleep disorders after the diagnosis of adrenal adenoma in patients compared to the referent subjects from the same population Methods: Using a medical records linkage system, we identified adult patients living in the Olmsted County, MN diagnosed with an adrenal adenoma during 1995–2017. Patients with overt hormone excess were excluded. Every patient with adenoma was matched by sex and age to a referent subject from the same population. Subjects were followed until death or end of the study. Mental health related comorbidities and sleep disorders were assessed at baseline and during follow up. Results: Our cohort included 1004 patients with adrenal adenomas and 1004 referent subjects (58% women, median age of 63 years). Patients were more likely to smoke (70% vs 54%, p <0.001) and had a higher BMI (30 kg/m2 vs 28 kg/m2, p < 0.001). Within 5 years prior to the index date (diagnosis of adenoma), and after adjusting for BMI and smoking, patients demonstrated a higher prevalence of depression (Odds ratio, OR of 1.3 (CI95% 1.1–1.6), p=0.02), anxiety (OR of 1.4 (CI95% 1.1–1.8, p=0.003), substance abuse disorders (OR of 2.4 (CI 95% 1.7–3.4), p<0.001), but not insomnia (OR of 1.2 (CI95% 0.9–1.7) and sleep related breathing disorders (OR of 1.3 (CI 95% 0.9–1.7). During follow-up, starting 1 year after the diagnosis, patients demonstrated a higher risk of new onset depression (HR of 1.9, CI95%1.5–2.4), anxiety (HR of 1.5,CI95% 1.2–1.9), schizophrenia (HR of 1.7, CI95% 1.2–2.4), and substance abuse disorders (HR of 1.6, CI95% 1.2–2.0). Risk of sleep disorders 1 year after diagnosis was also high for insomnia (HR of 1.4, CI95% 1.1–1.9), sleep-related breathing disorders (HR of 1.8, CI95% 1.4–2.3), hypersomnias of central origin (HR of 2.0, CI95%1.04–3.96), parasomnias (HR of 2.4, CI95%1.2–4.7), and sleep-related movement disorders(HR of 1.9, CI95%1.3–2.6). Conclusion: Patients with adenomas are at increased risk for mental and sleep disorders, possibly explained by the underlying subtle cortisol secretion. Further prospective studies with an in-depth characterization of both hormonal secretion and mental/sleep disorders are needed. Reversibility or improvement of mental health and sleep disorders with adrenalectomy should be investigated.

Treatment of central disorders of hypersomnolence: an American Academy of Sleep Medicine clinical practice guideline.

This guideline establishes clinical practice recommendations for the treatment of central disorders of hypersomnolence in adults and children. The American Academy of Sleep Medicine commissioned a task force of experts in sleep medicine to develop recommendations and assign strengths to each recommendation, based on a systematic review of the literature and an assessment of the evidence using the GRADE process. The task force provided a summary of the relevant literature and the quality of evidence, the balance of benefits and harms, patient values and preferences, and resource use considerations that support the recommendations. The AASM Board of Directors approved the final recommendations. The following recommendations are intended to guide clinicians in choosing a specific treatment for central disorders of hypersomnolence in adults and children. Each recommendation statement is assigned a strength ("strong" or "conditional"). A "strong" recommendation (ie, "We recommend…") is one that clinicians should follow under most circumstances. A "conditional" recommendation (ie, "We suggest…") is one that requires that the clinician use clinical knowledge and experience and strongly consider the individual patient's values and preferences to determine the best course of action. Under each disorder, strong recommendations are listed in alphabetical order followed by the conditional recommendations in alphabetical order. The section on adult patients with hypersomnia because of medical conditions is categorized based on the clinical and pathological subtypes identified in ICSD-3. The interventions in all the recommendation statements were compared to no treatment. We recommend that clinicians use modafinil for the treatment of narcolepsy in adults. (STRONG). We recommend that clinicians use pitolisant for the treatment of narcolepsy in adults. (STRONG). We recommend that clinicians use sodium oxybate for the treatment of narcolepsy in adults. (STRONG). We recommend that clinicians use solriamfetol for the treatment of narcolepsy in adults. (STRONG). We suggest that clinicians use armodafinil for the treatment of narcolepsy in adults. (CONDITIONAL). We suggest that clinicians use dextroamphetamine for the treatment of narcolepsy in adults. (CONDITIONAL). We suggest that clinicians use methylphenidate for the treatment of narcolepsy in adults. (CONDITIONAL). We recommend that clinicians use modafinil for the treatment of idiopathic hypersomnia in adults. (STRONG). We suggest that clinicians use clarithromycin for the treatment of idiopathic hypersomnia in adults. (CONDITIONAL). We suggest that clinicians use methylphenidate for the treatment of idiopathic hypersomnia in adults. (CONDITIONAL). We suggest that clinicians use pitolisant for the treatment of idiopathic hypersomnia in adults. (CONDITIONAL). We suggest that clinicians use sodium oxybate for the treatment of idiopathic hypersomnia in adults. (CONDITIONAL). We suggest that clinicians use lithium for the treatment of Kleine-Levin syndrome in adults. (CONDITIONAL). We suggest that clinicians use armodafinil for the treatment of hypersomnia secondary to dementia with Lewy bodies in adults. (CONDITIONAL). We suggest that clinicians use modafinil for the treatment of hypersomnia secondary to Parkinson's disease in adults. (CONDITIONAL). We suggest that clinicians use sodium oxybate for the treatment of hypersomnia secondary to Parkinson's disease in adults. (CONDITIONAL). We suggest that clinicians use armodafinil for the treatment of hypersomnia secondary to traumatic brain injury in adults. (CONDITIONAL). We suggest that clinicians use modafinil for the treatment of hypersomnia secondary to traumatic brain injury in adults. (CONDITIONAL). We suggest that clinicians use modafinil for the treatment of hypersomnia secondary to myotonic dystrophy in adults. (CONDITIONAL). We suggest that clinicians use modafinil for the treatment of hypersomnia secondary to multiple sclerosis in adults. (CONDITIONAL). We suggest that clinicians use modafinil for the treatment of narcolepsy in pediatric patients. (CONDITIONAL). We suggest that clinicians use sodium oxybate for the treatment of narcolepsy in pediatric patients. (CONDITIONAL). Maski K, Trotti LM, Kotagal S, et al. Treatment of central disorders of hypersomnolence: an American Academy of Sleep Medicine clinical practice guideline. J Clin Sleep Med. 2021;17(9):1881-1893.

Lipocalin-type prostaglandin D synthase levels increase in patients with narcolepsy and idiopathic hypersomnia.

Excessive daytime sleepiness (EDS) is a frequent cause for consultation and a defining symptom of narcolepsy and idiopathic hypersomnia (IH). The associated mechanisms remain unclear. Lipocalin-type prostaglandin D synthase (LPGDS) is a plausible sleep-inducing candidate. This study is to compare cerebral spinal fluid (CSF) and serum LPGDS levels in patients group with hypersomnia of central origin, including those with narcolepsy type 1 (NT1) and type 2 (NT2) and IH, to those in healthy controls (Con). Serum LPGDS, CSF LPGDS, and CSF hypocretin-1(Hcrt-1) levels were measured by ELISA in 122 narcolepsy patients (106 NT1 and 16 NT2), 27 IH, and 51Con. LPGDS levels in CSF (p = 0.02) and serum (p < 0.001) were 22%-25% lower in control subjects than in patients with EDS complaints, including NT1, NT2, and IH. In contrast to significant differences in CSF Hcrt-1 levels, CSF L-PGDS levels and serum L-PGDS were comparable among NT1, NT2, and IH (p > 0.05), except for slightly lower serum LPGDS in IH than in NT1 (p = 0.01). Serum L-PGDS correlated modestly and negatively to sleep latency on MSLT (r = -0.227, p = 0.007) in hypersomnia subjects. As a somnogen-producing enzyme, CSF/serum LPGDS may serve as a new biomarker for EDS of central origin and imply a common pathogenetic association, but would complement rather than replaces orexin markers.

Does excessive daytime sleepiness affect children's pedestrian safety?

Many cognitive factors contribute to unintentional pedestrian injury, including reaction time, impulsivity, risk-taking, attention, and decision-making. These same factors are negatively influenced by excessive daytime sleepiness (EDS), which may place children with EDS at greater risk for pedestrian injury. Using a case-control design, 33 children age 8 to 16 y with EDS from an established diagnosis of narcolepsy or idiopathic hypersomnia (IHS) engaged in a virtual reality pedestrian environment while unmedicated. Thirty-three healthy children matched by age, race, sex, and household income served as controls. Children with EDS were riskier pedestrians than healthy children. They were twice as likely to be struck by a virtual vehicle in the virtual pedestrian environment than healthy controls. Attentional skills of looking at oncoming traffic were not impaired among children with EDS, but decision-making for when to cross the street safely was significantly impaired. Results suggest excessive daytime sleepiness (EDS) from the clinical sleep disorders known as the hypersomnias of central origin may have significant consequences on children's daytime functioning in a critical domain of personal safety, pedestrian skills. Cognitive processes involved in safe pedestrian crossings may be impaired in children with EDS. In the pedestrian simulation, children with EDS appeared to show a pattern consistent with inattentional blindness, in that they "looked but did not process" information in their pedestrian environment. Results highlight the need for heightened awareness of potentially irreversible consequences of untreated sleep disorders and identify a possible target for pediatric injury prevention.

Maintenance of Wakefulness Test scores and driving performance in sleep disorder patients and controls

ObjectiveSleepiness at the wheel is a risk factor for traffic accidents. Past studies have demonstrated the validity of the Maintenance of Wakefulness Test (MWT) scores as a predictor of driving impairment in untreated patients with obstructive sleep apnea syndrome (OSAS), but there is limited information on the validity of the maintenance of wakefulness test by MWT in predicting driving impairment in patients with hypersomnias of central origin (narcolepsy or idiopathic hypersomnia). The aim of this study was to compare the MWT scores with driving performance in sleep disorder patients and controls. Methods19 patients suffering from hypersomnias of central origin (9 narcoleptics and 10 idiopathic hypersomnia), 17 OSAS patients and 14 healthy controls performed a MWT (4×40-minute trials) and a 40-minute driving session on a real car driving simulator. Participants were divided into 4 groups defined by their MWT sleep latency scores. The groups were pathological (sleep latency 0–19min), intermediate (20–33min), alert (34–40min) and control (>34min). The main driving performance outcome was the number of inappropriate line crossings (ILCs) during the 40minute drive test. ResultsPatients with pathological MWT sleep latency scores (0–19min) displayed statistically significantly more ILC than patients from the intermediate, alert and control groups (F (3, 46)=7.47, p<0.001). InterpretationPathological sleep latencies on the MWT predicted driving impairment in patients suffering from hypersomnias of central origin as well as in OSAS patients. MWT is an objective measure of daytime sleepiness that appears to be useful in estimating the driving performance in sleepy patients.

Co‐morbidity of complex genetic disorders and hypersomnias of central origin: lessons from the underlying neurobiology of wake and sleep

Appropriate wake and sleep cycles are important to physical well-being, and are modulated by neuronal networks in the brain. A variety of medical conditions can disrupt sleep or cause excessive daytime sleepiness. Clinical diagnostic classification schemes have historically lumped genetic disorders together into a category that considers the sleep dysfunction to be secondary to a medical condition. The unique nature of sleep endophenotypes that occur more frequently in particular genetic disorders has been underappreciated. Increased understanding of the pathophysiology of wake/sleep dysfunction in rare genetic disorders could inform studies of the neurological mechanisms that underlie more common forms of wake and sleep dysfunction. In this review, we highlight genetic developmental disorders in which sleep endophenotypes have been described, and then consider genetic neurodegenerative disorders with sleep characteristics that set them apart from the disruptions to sleep that are typically associated with aging and dementia.

Quality of life in patients with narcolepsy with cataplexy, narcolepsy without cataplexy, and idiopathic hypersomnia without long sleep time: Comparison between patients on psychostimulants, drug-naïve patients and the general Japanese population

To assess the quality of life of patients with narcolepsy with cataplexy (NA-CA), narcolepsy without cataplexy (NA w/o CA), and idiopathic hypersomnia without long sleep time (IHS w/o LST) who were taking psychostimulant medication, and to ascertain which factors (including psychosocial and environmental variables) influence quality of life in this population. In total, 185 patients who had received regular treatment were enrolled in the study (NA-CA, n=83; NA w/o CA, n=48; IHS w/o LST, n=54). Patients were asked to complete questionnaires including the Short Form-36 Health Survey (SF-36), the Epworth Sleepiness Scale (ESS), and items concerning psychosocial and environmental variables. All three diagnostic groups had significantly lower scores for most SF-36 domains compared with the Japanese normative data, and the ESS score was significantly reduced with treatment. Multiple logistic regression analyses revealed that several SF-36 domains were associated with the ESS score; autonomy in controlling own job schedule, experience of divorce or break up with a partner due to symptoms, experience of being forced to relocate or being dismissed due to symptoms, and perception of support from others. The severity of subjective sleepiness and psychological and environmental variables influenced quality of life in patients with these hypersomnias of central origin.

Sequence variants in circadian rhythmic genes in a cohort of patients suffering from hypersomnia of central origin

The mutation analysis of circadian genes in different sleep disorders revealed only a few disease-causing mutations so far. Cryptochrome 1 + 2 (CRY1, CRY2) and aryl hydrocarbon receptor nuclear translocator-like (ARNTL also known as BMAL1) are genes that play a major role in the adherence to circadian rhythm. Excessive daytime sleepiness (EDS) presents as the dissociation from the circadian rhythm and is the leading symptom of sleep disorders, which are summarised as hypersomnias of central origin. We performed an association studies in 86 German Caucasian patients suffering from EDS to analyze whether there is a genetic predisposition resulting from the involvement of sequence variants in the genes CRY1, CRY2 and ARNTL. One polymorphism in CRY1 was detected, which was associated with EDS regardless of the underlying specific sleep disorder. The result suggests that CRY1 could play a possible role in the complex genetics of hypersomnias of central origin.

Socio-professional handicap and accidental risk in patients with hypersomnias of central origin

Narcolepsy and idiopathic hypersomnia profoundly affect quality of life, education and work. Young patients are very handicapped by unexpected sleep episodes during lessons. Professionals frequently complain about sleepiness at work. Motor discomfort (i.e., cataplectic attacks) surprisingly is less handicapping in narcoleptics than sleepiness but only a few studies clearly assess the problem. Quality of life is also largely impaired in its physical and emotional dimensions. Sleepiness is the major factor explaining a decrease of quality of life and unexpectedly cataplectic attacks have little impact on patients. Another potential problem for these patients is the risk of accidents at work or when driving. Narcoleptic and hypersomniac patients have a higher risk of accidents than apneic or insomniac subjects. But, confounding factors such as duration of driving, number of cataplectic attacks or even objective level of alertness are not always entered in the analytic models mainly because of small samples of patients. Unlike in apneic patients, the effect of treatment on accidental risk has not been studied in narcoleptics or in hypersomniacs. Epidemiological data are needed to improve knowledge concerning these areas. Clinical trials assessing the impact of treatment on driving and work are also urgently needed. Finally, medical treatment does not seem to be completely efficient and physicians should pay more attention to the education, work, life and social environment of their patients.

Narcolepsy and other hypersomnias in children

We provide an update on the pathogenesis, diagnosis, assessment (clinical and laboratory), and treatment options for children with narcolepsy and other hypersomnias of central origin in order to raise awareness of these diseases and to highlight the clinical findings that should make the pediatrician suspect the diagnosis. Narcolepsy is a chronic rapid eye movement sleep disorder. Accumulating evidence indicates that signs of narcolepsy may start during childhood. Recent data suggest that a deficiency in the hypothalamic orexin/hypocretin system underlies the pathogenesis of narcolepsy with cataplexy. Confirmatory tests such as polysomnography, multiple sleep latency test, and actigraphy, along with referral to a sleep physician, maybe necessary in appropriate cases. Laboratory tests such as human leukocyte antigen typing and cerebrospinal fluid hypocretin-1 analysis are useful as adjuncts. Modafinil is now considered the first-line treatment for excessive sleepiness in adult patients with narcolepsy. Sodium oxybate is currently approved by the Food and Drug Administration for the treatment of narcolepsy with cataplexy in patients aged more than 16 years. Awareness of the extent of hypersomnia in children will allow physicians to effectively screen every child; once identified, further assessment should be performed in order to diagnose and treat the underlying cause. Better understanding of pathogenesis, availability of newer therapies with different mechanism of effect, and appropriately designed randomized clinical trials should allow improved management of children with narcolepsy.

New Guidelines on the Treatment of Excessive Sleepiness

The American Academy of Sleep Medicine (AASM) has produced new guidelines on the treatment of narcolepsy and of other hypersomnias of central origin, based on a comprehensive review of the literature. These guidelines are an update of the AASM guidelines on narcolepsy from 2000. The review emphasizes the importance of obtaining an accurate diagnosis by considering the differential diagnosis of disorders of excessive sleepiness. In recent years, important advances have been made in our understanding of the pathophysiology of narcolepsy and in treatment …

Treatment of Narcolepsy and other Hypersomnias of Central Origin

The purpose of this paper is to summarize current knowledge about treatment of narcolepsy and other hypersomnias of central origin. The task force performed a systematic and comprehensive review of the relevant literature and graded the evidence using the Oxford grading system. This paper discusses the strengths and limitations of the available evidence regarding treatment of these conditions, and summarizes key information about safety of these medications. Our findings provide the foundation for development of evidence-based practice parameters on this topic by the Standards of Practice Committee of the American Academy of Sleep Medicine. The majority of recent papers in this field provide information about use of modafinil or sodium oxybate for treatment of sleepiness associated with narcolepsy. Several large randomized, placebo-controlled studies indicate that modafinil and sodium oxybate are effective for treatment of hypersomnia due to narcolepsy. We identified no studies that report direct comparison of these newer medications versus traditional stimulants, or that indicate what proportion of patients treated initially with these medications require transition to traditional stimulants or to combination therapy to achieve adequate alertness. As with the traditional stimulants, modafinil and sodium oxybate provide, at best, only moderate improvement in alertness rather than full restoration of alertness in patients with narcolepsy. Several large randomized placebo-controlled studies demonstrate that sodium oxybate is effective for treatment of cataplexy associated with narcolepsy, and earlier studies provide limited data to support the effectiveness of fluoxetine and tricyclic antidepressants for treatment of cataplexy. Our findings indicate that very few reports provide information regarding treatment of special populations such as children, older adults, and pregnant or breastfeeding women. The available literature provides a modest amount of information about improvement in quality of life in association with treatment, patient preferences among the different medications, or patient compliance. Several recent studies provide evidence that modafinil and sodium oxybate are effective for treatment of hypersomnia due to narcolepsy. No studies were identified that report direct comparison of these newer medications with traditional stimulants. Despite significant advances in understanding the pathophysiology of narcolepsy, we do not have an ideal treatment to restore full and sustained alertness. Future investigations should be directed toward development of more effective and better tolerated therapies, and primary prevention.

Practice Parameters for the Treatment of Narcolepsy and other Hypersomnias of Central Origin

Practice Parameters for the Treatment of Narcolepsy and other Hypersomnias of Central Origin

Diagnosis of narcolepsy and idiopathic hypersomnia. An update based on the International Classification of Sleep Disorders, 2nd edition

Defining the precise nosological limits of narcolepsy and idiopathic hypersomnia is an ongoing process dating back to the first description of the two conditions. The most recent step forward has been done within the preparation of the second edition of the "International classification of sleep disorders" published in June 2005. Appointed by Dr Emmanuel Mignot, the Task Force on "Hypersomnias of central origin, not due to a circadian rhythm sleep disorder, sleep related breathing disorder, or other causes of disturbed nocturnal sleep" thoroughly revisited the nosology of narcolepsy and of idiopathic hypersomnia. Narcolepsy is now distinguished into three different entities, narcolepsy with cataplexy, narcolepsy without cataplexy and narcolepsy due to medical condition, and idiopathic hypersomnia into two entities, idiopathic hypersomnia with long sleep time and idiopathic hypersomnia without long sleep time. Nevertheless there are still a number of pending issues. What are the limits of narcolepsy without cataplexy? Is there a continuum in the pathophysiology of narcolepsy with and without cataplexy? Should sporadic and familial forms of narcolepsy with cataplexy appear as subgroups in the classification? Are idiopathic hypersomnia with long sleep time and idiopathic hypersomnia without long sleep time, two forms of the same condition or two different conditions? Is there a pathophysiological relationship between narcolepsy without cataplexy and idiopathic hypersomnia without long sleep time?

Hipersomnie Pochodzenia Ośrodkowego

Wzmożona senność jest zjawiskiem fizjologicznym po długim czuwaniu, na przykład pod koniec dnia [...]

P0082 HLA Class II studies in Korean narcolepsy patients: Additional predisposing effects of DQB1*0301 and protective effects of DQB1*0601 in trans of DQB1*0602

testing and low CSF hypocretin-1 was assessed and ICSD-2 criteria tested for hypersomnia of central origin. Methods: Case series of 121 patients with excessive daytime sleepiness recruited at St. Vincent’s Hospital, Suwon, Korea over a 5-year period from 2000–2004. Gold standard was ICSD-2 criteria. Patients completed the Stanford Sleep Inventory (SSI) and accepted HLA typing. Polysomnography (87%), MSLT (96%), and CSF hypocretin-1 measurements (53%) conducted in patients. Results: All subjects were classified by ICSD-2, resulting in 79 cases with narcolepsy–cataplexy, 22 narcolepsy without cataplexy (9 with possible cataplexy-like symptoms and 15 without any cataplexy), 20 Idiopathic Hypersomnia cases. Idiopathic Hypersomnia cases with (n = 2) and without (n = 18) long sleep time were pulled in a single category. Narcolepsycataplexy cases were 92% HLA positive with low hypocretin-1. Cataplexy at interview was predicted by validated SSI questions regarding cataplexy triggers. “Cataplexy-like” events were reported with similar frequency in narcolepsy without cataplexy and idiopathic hypersomnia groups: 7 cases (35%) with Idiopathic Hypersomnia and 8 cases (36.3%) with narcolepsy without cataplexy. Approximately half of the narcolepsy– cataplexy cases (55%) had a sleep-onset REM periods (SOREMP: in NSPG, REML 20 minutes) during nocturnal polysomnography. This was highly predictive as 87% of the subjects with REM latency below 20 minutes were hypocretin deficiency. Conclusion: The ICSD-2 was easily applicable in cases with typical cataplexy. In these cases, the MSLT and further evaluations were almost always positive and may thus not always be needed. Many patients without cataplexy were difficult to classify because of biologically heterogeneous characteristics.

Possible confusion between primary hypersomnia and adult attention-deficit/hyperactivity disorder

We explored the possibility of diagnostic confusion between hypersomnias of central origin (narcolepsy and idiopathic hypersomnia, IH) and the adult form of attention-deficit/hyperactivity disorder (ADHD). We included 67 patients with narcolepsy, 7 with IH and 61 with ADHD. All patients completed the Epworth Sleepiness Scale and the ADHD Rating Scale. We found that 18.9% of the hypersomnia patients fulfilled the self-reported criteria for ADHD in adulthood, compared with 77% of the ADHD patients. A score ≥ 12 on the Epworth Sleepiness Scale (usually regarded to indicate excessive daytime sleepiness) was found in 37.7% of the ADHD patients compared 95.9% of the hypersomnia patients. In ADHD patients, inattention scores correlated with the excessive daytime sleepiness score. We conclude that one should be aware of possible diagnostic confusion between narcolepsy or IH and adult ADHD when using self-report questionnaires. The high percentage of symptom overlap found in our study raises questions about possible misdiagnosing of both conditions, comorbidity with sleep problems in adult ADHD, and the validation of the used scales. It remains unclear whether our findings indicate pathophysiological overlap.