Sleep Month in Review: January 2024

New year, new sleep habits. Brand-new studies in January 2024 examined sleep associations, looking at specific sleep disorders such as insomnia and obstructive sleep apnea.

In this month in review, we highlighted the 5 biggest stories in sleep.

Highlighting Sleep Apnea Data

Periodic Limb Movements During Sleep Linked to Cardiovascular Disease, Death

A study found periodic limb movements during sleep are linked to cardiovascular disease events (CVD) or death. The study aimed to see if periodic limb movements during obstructive sleep apnea (OSA) were independent or synergistic factors for CVD events or death. The investigators did not find an interaction between the apnea-hypopnea index and periodic limb movements index, which showed there was no synergy between mild-moderate OSA and periodic limb movements for the risk of CVD or death. However, analyses showed periodic limb movement index was linked to an increased risk of incident CVD or death.

Sleep Apnea Serves as a Risk Factor for Uncontrolled, Severe Asthma

Asthma is more likely to be uncontrolled or severe in adults who are at a high risk for OSA, a study found. The investigators conducted a cross-sectional study at an allergy department with adult asthma patients. Participants were recruited to the department while undergoing routine lung function tests from January 2022 – December 2022. Multivariable analyses showed an increased risk of having uncontrolled asthma was associated with those at high risk for OSA, women, having uncontrolled rhinitis, and Global Initiative for Asthma treatment steps.

Night Sweats Could Shed Light on Sleep Apnea Stage

An observational and prospective study found a way to determine the severity of OSA: measuring night sweats, specifically sweat metabolomes. The Apnea-Hypopnea Index is used to diagnose OSA, measuring the episodes of shortness of breath occurring per house. However, the index fails to provide enough information about OSA since it only accounts for the number of episodes, not episode severity. The investigators found the oxygen desaturation index works well when diagnosing sleep apnea as it shows how serious episodes are by calculating the number of events where oxygen saturation has reduced by < 3%.

Data on Poor Sleep Affecting Cognition

Disrupted Sleep in 30s and 40s Linked to Cognitive Problems a Decade Later

People who have disrupted sleep in their 30s and 40s could be at a greater risk of memory and thinking problems a decade later, according to a study. Investigators conducted an analysis leveraging data from the CARDIA study. They examined the sleep duration and quality of 500 individuals from their mid-30s to late 40s as well as midlife cognition assessments 11 years later. Participants wore wrist actigraphy from 2003 – 2005 to track sleep. Analyses found participants who had the highest sleep fragmentation index were twice as likely to have poor cognitive performance in midlife.

Cognitive Behavioral Therapy for Insomnia

Study Pinpoints Critical, Unnecessary Components of CBT for Insomnia

A systemic review and component network meta-analysis found the most critical, most helpful components of cognitive behavioral therapy (CBT) for insomnia are cognitive restructuring, third-wave components, sleep restrictions, and stimulus control. CBT was also more efficient when delivered in person. Additionally, the study found sleep hygiene and sleep diary were inert, and relaxation was potentially counterproductive. The investigators analyzed randomized clinical trials published from 1980 – 2023 that compared any form of CBT against another form of CBT or a control. Participants were aged ≥ 18 years ago with chronic insomnia.