Researchers find a significant positive correlation between self-reported daytime sleepiness and attention problems for adult patients with narcolepsy and idiopathic hypersomnia, with both genders being affected equally.

The objective of research study “ADHD Symptoms Reported in Adults with Narcolepsy and Idiopathic Hypersomnia” was to examine the presence of attentional difficulties in hypersomnia by assessing current ADHD (attention deficit hyperactivity disorder) symptoms in adult patients diagnosed with narcolepsy type 1 (NT1), narcolepsy type 2 (NT2), and idiopathic hypersomnia (IH).

The three clinical diagnostic groups in this study are categorized as disorders of central hypersomnolence by the ICSD-3. “Patients with these conditions report subjective experiences with sleepiness and attention similarly, warranting their combined inclusion in a study assessing the relationship between self-reported attention and daytime sleepiness among those with hypersomnia,” say research abstract authors Sara Kowalczyk, MA, MPH, a doctoral candidate in behavioral neuroscience at Boston University, and William DeBassio, PhD, MD, an associate professor of neurology at Boston University, in an e-mail to Sleep Review.

Background and Results

Dr William DeBassio, who also is a physician in the department of pediatric neurology at the Boston Medical Center, says the clinical assessment of attention is likely to be additive in treating patients with hypersomnia. “If attention and sleep are related, and the results from this study suggest that they are, then clinical assessment of both may be important to optimal clinical treatment for hypersomnia,” says DeBassio. “While many clinicians use tools like the Epworth Sleepiness Scale (ESS) to identify how their patients’ sleepiness changes over time, the use of attention-related clinical screening questionnaires may be equally useful, but currently under-utilized.”

For the study, 833 participants reporting a diagnosed hypersomnia condition from a physician and completed the Adult ADHD Self-Report Scale (ASRS) v1.1 and the ESS via an online survey. Over 60% screened positive for the likelihood of ADHD on the ASRS, while less than 13% self-reported having an ADHD diagnosis. In addition, there were no significant differences between the type of hypersomnia diagnosis on the ASRS or ESS.

The analysis also found:

  • both genders reported problematic attention and ADHD diagnoses equally;
  • there was a significant positive association between self-reported daytime sleepiness and attention deficiencies in an adjusted linear regression model;
  • An adjusted, final linear regression model indicated that greater attentional deficiencies were also significantly predicted by:
    • younger current age
    • having a co-morbid depression diagnosis
    • greater self-reported impulsivity
    • greater current self-reported disease severity
    • shorter current self-reported nighttime sleep length

The abstract, published in Sleep, notes that a linear regression analysis revealed a positive, significant relationship between ASRS and ESS variables. Essentially, the results indicate that self-reported attention and sleepiness are correlated among those with a central hypersomnia disorder. The clinical assessment of attentional deficiencies in individuals with a hypersomnia diagnosis may improve outcomes in patients with IH, NT1, and NT2.

Study Limitations

This research study was on a subset of participants in a sizeable anonymous survey research study, the Boston University Narcolepsy and Idiopathic Hypersomnia Patient Perspectives Study (BUNIHPPS). Due to the anonymous survey methodology, Kowalczyk and DeBassio note that a limitation of their study is that verification of diagnoses was not possible. Recruitment for the survey study took place through social media and patient advocacy organization announcements, with research brochures made available in 10 sleep clinics based in the United States. As such, Kowalczyk and DeBassio note that participants might not be representative of the total hypersomnia patient population due to self-selection bias.

Implications for Sleep Medicine

According to Kowalczyk and DeBassio, this study is the first to quantify the presence of current self-reported attention problems among hypersomnia patients using a validated adult ADHD screening questionnaire. That 60% of patients score in a range indicating likely ADHD is an important finding for sleep medicine physicians treating hypersomnia patients. “The study’s significant results positively correlate increasing sleepiness with more attentional problems, across multiple hypersomnia diagnostic categories and affecting both genders equally,” says Kowalczyk.

The findings indicate that the clinical assessment of attentional deficiencies can improve narcolepsy outcomes. According to Kowalczyk and DeBassio, attention can be assessed in adult patients using the ASRS v1.1. The free and easily accessible assessment, created by the World Health Organization, can be administered in either a 6 or 18 question version, and the summary scores can help clinicians by quickly identifying the hypersomnia patients who have self-reported problems with attention.

“Clinical assessment of attention may be useful in treating patients with hypersomnia due to the significant relationship with sleepiness,” say Kowalczyk and DeBassio. “Furthermore, assessing self-reported attention among adults using the ASRS v1.1 is quick, accurate, free, and easy to incorporate to a clinical setting.”

Kowalczyk and DeBassio say future research should focus on replicating the correlation between attentional deficiencies and increasing daytime sleepiness from large hypersomnia patient databases or registries for both adults and children. “Imaging studies including fMRI with objective attentional tasks may improve the understanding of the neural circuitry involved in performing attention tasks among those with hypersomnia, and in comparison controls or those with ADHD only,” explain Kowalczyk and DeBassio. “Future research should address how hypersomnia patients may be affected by the inattentive and hyperactive sub-types of ADHD.”

Cassandra Perez is associate editor for Sleep Review. CONTACT cperez[at]