Our aim was to compare subjective and objective sleep quality and arousal in migraine and to evaluate the relationship between sleep quality and pain thresholds (PT) in controls, interictal, preictal and postictal migraine.

The mechanisms associating sleep and migraine are unknown. No previous polysomnographic (PSG) or pain-threshold (PT) study has compared patients with sleep-related migraine attacks (SM), non-sleep related migraine attacks (NSM) and healthy controls.

We aimed to compare subjective and objective sleep quality in tension-type headache (TTH) patients and to evaluate the relationship between sleep quality and pain thresholds (PT) in controls and TTH patients. A blinded cross-sectional study where polysomnography (PSG) and PT (to pressure, heat and cold) measurements were done in 20 patients with TTH (eight episodic (ETTH) and twelve chronic (CTTH) TTH) and 29 healthy controls. Sleep diaries and questionnaires were applied. TTH patients had more anxiety (p = 0.001), insomnia (p < 0.0005), daytime tiredness (p < 0.0005) and reduced subjective sleep quality (p < 0.0005) compared to healthy controls. Sleep diaries revealed more long awakenings in TTH (p = 0.01) but no total sleep-time differences. TTH patients had more slow-wave sleep (p = 0.002) and less fast arousals (p = 0.004) in their PSGs. CTTH subjects had lower pressure PT (p = 0.048) and more daytime sleepiness than the controls (p = 0.039). Among TTH lower cold PT (CPT) correlated inversely with light sleep (N1) (r = −0.49, p = 0.003) while slow arousals correlated inversely with headache-frequency (r = −0.64, p = 0.003). We hypothesize that TTH patients need more sleep than healthy controls and might be relatively sleep deprived. Inadequate sleep may also contribute to increased pain sensitivity and headache frequency in TTH.

Sleeping problems are very common, and many patients need a comprehensive assessment with polysomnography, possibly followed by a sleep latency test. These methods and indications for the tests are described below. The article is based on the authors' own literature archives, clinical experience and Retningslinjer for metoder i klinisk neurofysiologi [Guidelines for methodology in clinical neurophysiology] Polysomnography involves monitoring sleep through the course of one night and scoring the stages of sleep on the basis of EEG activity, eye movements and muscular tension. Also recorded are inter alia respiratory variables. Polysomnography followed by a multiple sleep latency test (MSLT) is used when narcolepsy or excessive daytime sleepiness is suspected. If parasomnia is suspected, the examination should include polysomnography, preferably with video recording. If sleep apnoea is suspected in adults, respiratory polygraphy is often sufficient. As a rule, polysomnography is preferable to respiratory polygraphy for studying sleep disorders in children. Sleep disorders take many forms and are dealt with by many different specialities. Good cooperation between the different specialities is necessary to ensure an optimal result for the patients.

Assess the prognostic ability of a non-highly malignant and reactive EEG to predict good outcome after cardiac arrest (CA). Prospective observational multicentre substudy of the "Targeted Hypothermia versus Targeted Normothermia after Out-of-hospital Cardiac Arrest Trial", also known as the TTM2-trial. Presence or absence of highly malignant EEG patterns and EEG reactivity to external stimuli were prospectively assessed and reported by the trial sites. Highly malignant patterns were defined as burst-suppression or suppression with or without superimposed periodic discharges. Multimodal prognostication was performed 96 hours after CA. Good outcome at 6 months was defined as a modified Rankin Scale score of 0-3. 873 comatose patients at 59 sites had an EEG assessment during the hospital stay. Of these, 283 (32%) had good outcome. EEG was recorded at a median of 69 hours (IQR 47-91) after CA. Absence of highly malignant EEG patterns was seen in 543 patients of whom 255 (29% of the cohort) had preserved EEG reactivity. A non-highly malignant and reactive EEG had 56% (CI 50-61) sensitivity and 83% (CI 80-86) specificity to predict good outcome. Presence of EEG reactivity contributed (p<0.001) to the specificity of EEG to predict good outcome compared to only assessing background pattern without taking reactivity into account. Nearly one-third of comatose patients resuscitated after CA had a non-highly malignant and reactive EEG that was associated with a good long-term outcome. Reactivity testing should be routinely performed since preserved EEG reactivity contributed to prognostic performance.