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The interaction between sleep and disease is often complex. In epilepsy, seizure risk is modulated by sleep pressure and sleep stage. At the same time, sleep can be affected by both seizures and anti-epileptic drugs (Bazil, 2017; Derry & Duncan, 2013). Polysomnography (PSG) recordings, the laboratory-recorded gold-standard, pose several disadvantages for clinical use. PSG is expensive, time-consuming and requires a trained technician. Furthermore, the individual will normally be required to stay in the laboratory/hospital, which often limits the number of monitoring nights to one or two. Reliable sleep monitoring that can be conducted in the individuals' home environment for longer periods of time is therefore desirable (Vojkan, Grundlehner, Vullers, & Penders, 2015). Although a full PSG montage is sometimes required for diagnosing primary sleep disorders, a smaller-scale system focusing on electroencephalogram (EEG) might be sufficient when we are not diagnosing primary sleep disorders but rather seek to use sleep monitoring as a tool for optimizing treatment in individuals with sleep disturbances, such as those found in epilepsy. In the past decade, several types of mobile EEG systems for sleep measurements have been presented. Some of these sys

Sustaining a weight loss after a lifestyle intervention is challenging. The objective of the present study was to investigate if mitochondrial function is associated with the ability to maintain a weight loss. Sixty-eight former participants in an 11–12-week lifestyle intervention were recruited into 2 groups; weight loss maintenance (WLM; body mass index (BMI): 32 ± 1 kg/m2) and weight regain (WR; BMI: 43 ± 2 kg/m2) based on weight loss measured at a follow-up visit (WLM: 4.8 ± 0.4; WR: 7.6 ± 0.8 years after lifestyle intervention). Maximal oxygen consumption rate, physical activity level, and blood and muscle samples were obtained at the follow-up experiment. Mitochondrial respiratory capacity and reactive oxygen species (ROS) production were measured. Fasting blood samples were used to calculate glucose homeostasis index. WR had impaired glucose homeostasis and decreased maximal oxygen uptake and physical activity level compared with WLM. The decreased physical activity in WR was due to a lower activity level at vigorous and moderate intensities. Mitochondrial respiratory capacity and citrate synthase (CS) activity was higher in WLM, but intrinsic mitochondrial respiratory capacity (mitochondrial respiratory capacity corrected for mitochondrial content (CS activity)) was similar. ROS production was higher in WR compared with WLM, which was accompanied by a decreased content of antioxidant proteins in WR. Intrinsic mitochondrial respiratory capacity in skeletal muscle is not associated with the ability to maintain a long-term weight loss. WLM had a higher maximal oxygen uptake, physical activity level, mitochondrial respiratory capacity and CS activity compared with WR. The reduced glucose tolerance was concurrent with increased ROS production per mitochondria in WR, and could also be associated with the lower physical activity level in this group.

SummaryThe interest in sleep as a potential clinical biomarker is growing, but the standard method of sleep assessment, polysomnography, is expensive, time consuming, and requires a lot of expert assistance for both set‐up and interpretation. To make sleep analysis more available both in research and in the clinic, there is a need for a reliable wearable device for sleep staging. In this case study, we test ear‐electroencephalography. A wearable, where electrodes are placed in the outer ear, as a platform for longitudinal at‐home recording of sleep. We explore the usability of the ear‐electroencephalography in a shift work case with alternating sleep conditions. We find the ear‐electroencephalography platform to be reliable both in terms of showing substantial agreement to polysomnography after long‐time use (with an overall agreement, using Cohen's kappa, of 0.72) and by being unobtrusive enough to wear during night shift conditions. We find that fractions of non‐rapid eye movement sleep and transition probability between sleep stages show great potential as sleep metrics when exploring quantitative differences in sleep architecture between shifting sleep conditions. This study shows that the ear‐electroencephalography platform holds great potential as a reliable wearable for quantifying sleep “in the wild”, pushing this technology further towards clinical adaptation.