A longitudinal study of older Chinese adults found that those with a self-reported, habitual short sleep duration of five hours or less had a significantly increased risk of developing memory impairment during a mean follow-up period of four years. The association remained significant after excluding those with poor self-reported health. The results are published in the November issue of SLEEP.

A study in the November issue of SLEEP suggests that the intermittent hypoxia associated with obstructive sleep apnea (OSA) could induce fertility reduction in male patients. The study mimicked OSA in a case-control comparison using a mouse model. According to a commentary on the study, a possible “sperm crisis” may be occurring, due in part to the increasing incidence in sleep disturbance.

A study in the November issue of SLEEP suggests that insomnia is a major contributor to deaths caused by motor vehicle crashes and other unintentional fatal injuries. The results underscore the importance of healthy sleep for public health and safety, notes the National Healthy Sleep Awareness Project. 

A study in the Oct. 29 issue of the Journal of Neuroscience demonstrates a novel role for rapid eye movement (REM) sleep in human memory formation and highlights a significant cognitive consequence of obstructive sleep apnea (OSA).

A study in the October issue of the Journal of Clinical Sleep Medicine found that race-ethnicity may moderate the relationship between continuous positive airway pressure (CPAP) adherence and some functional outcomes of sleep. The study involved 227 veterans with obstructive sleep apnea (OSA). According to the authors, longitudinal studies of diverse patients with OSA are needed to replicate these findings.

The craniofacial structures that have been associated with obstructive sleep apnea are heritable, according to a study in the October issue of SLEEP. Heritability was confirmed for features such as mandibular length and width, maxillary width and size of the oropharyngeal space.

Residual obstructive sleep apnea (OSA) after adenotonsillectomy may be partly due to the smaller sizes of the mandible in pediatric patients, according to a Japanese study in the September issue of the Journal of Clinical Sleep Medicine. According to the authors, maxillomandibular morphology should be examined carefully when developing a treatment plan for OSA in children.

Alterations of microRNAs (miRNAs) may be involved in the pathophysiology of central hypersomnias, suggests a study in the September issue of SLEEP. Results show that the levels of four miRNAs differed in plasma from patients with type 1 narcolepsy, type 2 narcolepsy and idiopathic hypersomnia. According to the authors, looking at the targets of these miRNAs will promote understanding of the pathogenesis of central hypersomnias.

A study in the September issue of SLEEP found that the risk of an extended absence from work due to sickness rose sharply among those who reported sleeping less than 6 hours or more than 9 hours per night. The results underscore the importance of the “Sleep Well, Be Well” campaign of the National Healthy Sleep Awareness Project.

A new study in the August issue of the Journal of Clinical Sleep Medicine evaluated the feasibility of comprehensive home sleep apnea testing, including electroencephalography (EEG), in 201 school-aged children.