News & Noteworthy
Sleep duration and body mass index in twins: a gene-environment interaction.
Twin study(1,088 pairs, 604 monozygotic, 484 dizygotic) indicates that individuals genetically susceptible to obesity are more likely to become obese if they are short sleepers (<7 hours). Longer, but genetically susceptible, were less likely to put on weight.
An investigation of the relationship between subjective sleep quality, loneliness and mood in an Australian sample: Can daily routine explain the links?
"This study provides an important independent replication of the association between poor sleep and loneliness. However, the mechanism underlying this link remains unclear. A theoretically plausible mechanism for this link, lifestyle regularity, does not explain the relationship between loneliness and poor sleep. The nexus between loneliness and poor sleep is unlikely to be broken by altering the social rhythm of patients who present with poor sleep and loneliness."
REM Sleep Instability – A New Pathway for Insomnia?
Objective studies consistently show that insomniacs sleep more than they perceive. Prof Riemann & collaborators show however that there is a difference between insomniacs and good sleepers in the time spent awake and the number of arousals in REM sleep.
Hypnotics' association with mortality or cancer: a matched cohort study.
Kripke has long noted the correlation between short and long sleep and mortality, AND the association between sleeping pill usage and mortality. The newest study shows how few sleeping pills/year are necessary for this association to become significant. The studies do not show causality - it may be the case that for some people impaired sleep is the first sign of things going wrong with the body ...
Sleep education for paradoxical insomnia.
Sleep education holds promise for some paradoxical insomnia patients.
ABCC9 gene affects sleep duration
Following the observation that long or short sleep duration is associated with metabolic syndrome, and that sleep duration is affected by season, 'biological clock type' (chronotype (lark/owl)) and human familial disorders led to a German group to do a genetics study in 7 European populations. They found a variant in the ABCC9 gene affected 5% of the variation in sleep duration.
Grief associated with sleep problems
Over 20% of soldiers reported difficulty coping with grief. he most frequent physical health symptoms reported were: sleep problems (32.8%), musculoskeletal pain (32.7%), fatigue (32.3%), and back pain (28.1%). Difficulty coping with grief over the death of someone close affected 21.3%.
Loneliness Is Associated with Sleep Fragmentation in a Communal Society
Loneliness was a significant predictor of sleep fragmentation. Humans’ social nature may partly be manifest through our depen- dence on feeling secure in our social environment to sleep well.
Sleep deprivation alters valuation signals in the ventromedial prefrontal cortex.
Researchers using fMRI found that the ventromedial prefrontal cortex was affected by sleep deprivation and impacted on the valuation of monetary and social rewards
No pain, no gain - sleep restriction for insomnia
A study exploring the patient side of sleep restriction therapy (essentially restricting the time in bed to the time that you can sleep as assessed by a sleep diary). The participants had suffered from insomnia for an average of 17 years. The study found that the insomniacs improved long-term, though as the title suggests, those suffering from most side-effects fatigue/exhaustion’ (100%), ‘extreme sleepiness’ (94%), ‘reduced motivation/energy’ (89%) and ‘headache/migraine’ (72%) in general improved the most.
Orexin involved in inflammation-induced lethargy
Orexin is one of the many brain chemicals that are involved in the control of sleep and wakefulness. For example, reduced levels or activity of the orexin system is involved in narcolepsy a sleep disorder that is characterised by uncontrollable sleep. It has now been found that the lethargy associated with illness is also mediated by orexin.
Sleep is for brain restoration?
Two references on this page: 1) A Journal of Neuroscience paper 2010 and 2) current editorials on the subject in the Sleep Journal. The paper looked directly at energy levels in various parts of the brain and found increases in energy carrying molecules after deep sleep.
24 hour rhythms impact on the heart
Death from heart disease occurs mainly in the morning. Our 24h rhythms affect our heart and blood pressure differently throughout the day.
Insomnia linked to high insulin resistance in diabetics
Study finding that poor sleepers had 23% higher blood glucose levels and 48% higher blood insulin levels in the morning. The estimated insulin resistance in poor sleepers was 82% higher than normal sleepers with diabetes.
Behavioural sleep treatments and night time crying in infants: Challenging the status quo.
This paper challenges the aetiology and acceptance of the status quo in the hope of revisiting the underlying belief that these methods are necessary.
