Unique sleep‐stage transitions determined by obstructive sleep apnea severity,age and gender

In obstructive sleep apnea, patients’ sleep is fragmented leading to excessive daytime sleepiness and co‐morbidities like arterial hypertension. However, traditional metrics are not always directly correlated with daytime sleepiness, and the association between traditional sleep quality metrics like sleep duration and arterial hypertension is still ambiguous. In a development cohort, we analysed hypnograms from mild (n = 209), moderate (n = 222) and severe (n = 272) obstructive sleep apnea patients as well as healthy controls (n = 105) from the European Sleep Apnea Database. We assessed sleep by the analysis of two‐step transitions depending on obstructive sleep apnea severity and anthropometric factors. Two‐step transition patterns were examined for an association to arterial hypertension or daytime sleepiness. We also tested cumulative distributions of wake as well as sleep‐states for power‐laws (exponent α) and exponential distributions (decay time τ) in dependency on obstructive sleep apnea severity and potential confounders. Independent of obstructive sleep apnea severity and potential confounders, wake‐state durations followed a power‐law distribution, while sleep‐state durations were characterized by an exponential distribution. Sleep‐stage transitions are influenced by obstructive sleep apnea severity, age and gender. N2 → N3 → wake transitions were associated with high diastolic blood pressure. We observed higher frequencies of alternating (symmetric) patterns (e.g. N2 → N1 → N2, N2 → wake → N2) in sleepy patients both in the development cohort and in a validation cohort (n = 425). In conclusion, effects of obstructive sleep apnea severity and potential confounders on sleep architecture are small, but transition patterns still link sleep fragmentation directly to obstructive sleep apnea‐related clinical outcomes like arterial hypertension and daytime sleepiness.     

A cross-national comparison of the Twitter feeds of popular alcohol brands in India and Australia

Aims: To evaluate (i) the types of techniques alcohol marketers utilise to facilitate user engagement with content on leading Indian and Australian Twitter alcohol brand pages and (ii) the extent to which users engage with this content in two diverse national contexts.

Methods: The 10 alcohol brands per country with the greatest Twitter presence were identified based on the number of ‘followers’. Number of tweets, photos, and videos were collected and the type of content noted for each brand between 1 January 2016 and 29 February 2016. The data were analysed via an inductive coding approach using NVivo10.

Results: In total, the brands had accumulated up to 150,386 followers (Indian: 110,032; Australian: 40,354). The techniques utilised were a mix of those that differed by country (e.g. India: sexually suggestive content versus Australia: posts related to the brand’s tradition or heritage) and generic approaches (e.g. alcohol sponsorship of sport, music, and fashion; offering consumption suggestions; organising competitions; giveaways; and use of memes).

Conclusions: The flexibility of Twitter, which complements traditional marketing, allows brands to adapt and deliver their online alcohol content in specific national contexts and to capitalise on the cultural meanings users invoke in their interactions with the brands.     

Mechanical and morphological determinants of peak power output in elite cyclists

Mechanical peak power output (PPO) is a determinant of performance in sprint cycling. The purpose of this study was to examine the relationship between PPO and putative physiological determinants of PPO in elite cyclists, and to compare sprint performance between elite sprint and endurance cyclists. Thirty-five elite cyclists (18 endurance; 17 sprint) performed duplicate sprint cycling laboratory tests to establish PPO and its mechanical components. Quadriceps femoris (Q_VOL) and hamstring muscle volume (HAM_VOL) were assessed with MRI, vastus lateralis pennation angle (Pθ_VL) and fascicle length (FL_VL) were determined with ultrasound imaging, and neuromuscular activation of three muscles was assessed using EMG at PPO during sprint cycling. For the whole cohort, there was a wide variability in PPO (range 775-2025 W) with very large, positive, bivariate relationships between PPO and Q_VOL (r = .87), HAM_VOL (r = .71), and Pθ_VL (r = .81). Step-wise multiple regression analysis revealed that 87% of the variability in PPO between cyclists was explained by two variables Q_VOL (76%) and Pθ_VL (11%). The sprint cyclists had greater PPO (+61%; P < .001 vs endurance), larger Q_VOL (P < .001), and BF_VOL (P < .001) as well as more pennate vastus lateralis muscles (P < .001). These findings emphasize the importance of quadriceps muscle morphology for sprint cycling events.     

Disruption of hippocampal rhythms via optogenetic stimulation during the critical period for memory development impairs spatial cognition

BackgroundHippocampal oscillations play a critical role in the ontogeny of allocentric memory in rodents. During the critical period for memory development, hippocampal theta is the driving force behind the temporal coordination of neuronal ensembles underpinning spatial memory. While known that hippocampal oscillations are necessary for normal spatial cognition, whether disrupted hippocampal oscillatory activity during the critical period impairs long-term spatial memory is unknown. Here we investigated whether disruption of normal hippocampal rhythms during the critical period have enduring effects on allocentric memory in rodents.Objective/hypothesisWe hypothesized that disruption of hippocampal oscillations via artificial regulation of the medial septum during the critical period for memory development results in long-standing deficits in spatial cognition.MethodsAfter demonstrating that pan-neuronal medial septum (MS) optogenetic stimulation (465 nm activated) regulated hippocampal oscillations in weanling rats we used a random pattern of stimulation frequencies to disrupt hippocampal theta rhythms for either 1Hr or 5hr a day between postnatal (P) days 21–25. Non-stimulated and yellow light-stimulated (590 nm) rats served as controls. At P50-60 all rats were tested for spatial cognition in the active avoidance task. Rats were then sacrificed, and the MS and hippocampus assessed for cell loss. Power spectrum density of the MS and hippocampus, coherences and voltage correlations between MS and hippocampus were evaluated at baseline for a range of stimulation frequencies from 0.5 to 110 Hz and during disruptive hippocampal stimulation. Unpaired t-tests and ANOVA were used to compare oscillatory parameters, behavior and cell density in all animals.ResultsNon-selective optogenetic stimulation of the MS in P21 rats resulted in precise regulation of hippocampal oscillations with 1:1 entrainment between stimulation frequency (0.5–110 Hz) and hippocampal local field potentials. Across bandwidths MS stimulation increased power, coherence and voltage correlation at all frequencies whereas the disruptive stimulation increased power and reduced coherence and voltage correlations with most statistical measures highly significant (p < 0.001, following correction for false detection). Rats receiving disruptive hippocampal stimulation during the critical period for memory development for either 1Hr or 5hr had marked impairment in spatial learning as measured in active avoidance test compared to non-stimulated or yellow light-control rats (p < 0.001). No cell loss was measured between the blue-stimulated and non-stimulated or yellow light-stimulated controls in either the MS or hippocampus.ConclusionThe results demonstrated that robust regulation of hippocampal oscillations can be achieved with non-selective optogenetic stimulation of the MS in rat pups. A disruptive hippocampal stimulation protocol, which markedly increases power and reduces coherence and voltage correlations between the MS and hippocampus during the critical period of memory development, results in long-standing spatial cognitive deficits. This spatial cognitive impairment is not a result of optogenetic stimulation-induced cell loss.     

Cyberchondria in First Year Medical Students of Yogyakarta

Abstract

Cyberchondria is a relatively new term addressing health anxiety associated with online information. Research data is scarce, as most instruments measuring anxiety do not consider online behavior an important factor. Medical students are arguably assumed to have frequent health anxieties, i.e. “medical student syndrome.” Moreover, they are exposed to large amounts of information. We aimed to measure the level of cyberchondria severity of first-year medical students. First-year medical students of the regular program at Universitas Gadjah Mada completed self-reported instruments (the Cyberchondria Severity Scale (CSS) and the Beck Anxiety Inventory (BAI)). Cut off was determined using ROC analysis to find the best score that corresponded to BAI cut off of 16. Data were analyzed using chi square and t-tests to analyze any differences between gender. Respondents were 162 students, 54 males and 108 females, with mean age 18.18-year-old ± 0.696. Based on ROC analysis, cut off of 75.5 corresponded with BAI score of 16. Mean CSS score was 70.73 ± 16.292. There was no significant difference of CSS scores between genders. Based on the analysis of individual items, compared to male students, female students more frequently searched for physical symptoms on the Internet, and afterwards, consulted the results with a General Practitioner (GP), discussed with a GP, or went to other specialists; and thus, more frequently required reassurance after online search. In contrast, male students more frequently had difficulty relaxing after searching online for physical symptoms. We concluded that there was no difference of overall cyberchondria severity score, but there were slight but significant differences of online behavior between genders.     

An adaptive case management system to support integrated care services: Lessons learned from the NEXES project

BackgroundExtensive deployment and sustainability of integrated care services (ICS) constitute an unmet need to reduce the burden of chronic conditions. The European Union project NEXES (2008–2013) assessed the deployment of four ICS encompassing the spectrum of severity of chronic patients.ObjectiveThe current study aims to (i) describe the open source Adaptive Case Management (ACM) system (Linkcare®) developed to support the deployment of ICS at the level of healthcare district; (ii) to evaluate its performance; and, (iii) to identify key challenges for regional deployment of ICS.MethodsWe first defined a conceptual model for ICS management and execution composed of five main stages. We then specified an associated logical model considering the dynamic runtime of ACM. Finally, we implemented the four ICS as a physical model with an ICS editor to allow professionals (case managers) to play active roles in adapting the system to their needs. Instances of ICS were then run in Linkcare®. Four ICS provided a framework for evaluating the system: Wellness and Rehabilitation (W&R) (number of patients enrolled in the study (n) = 173); Enhanced Care (EC) in frail chronic patients to prevent hospital admissions, (n = 848); Home Hospitalization and Early Discharge (HH/ED) (n = 2314); and, Support to remote diagnosis (Support) (n = 7793). The method for assessment of telemedicine applications (MAST) was used for iterative evaluation.ResultsLinkcare® supports ACM with shared-care plans across healthcare tiers and offers integration with provider-specific electronic health records. Linkcare® successfully contributed to the deployment of the four ICS: W&R facilitated long-term sustainability of training effects (p < 0.01) and active life style (p < 0.03); EC showed significant positive outcomes (p < 0.05); HH/ED reduced on average 5 in-hospital days per patient with a 30-d re-admission rate of 10%; and, Support, enhanced community-based quality forced spirometry testing (p < 0.01). Key challenges for regional deployment of personalized care were identified.ConclusionsLinkcare® provided the required functionalities to support integrated care adopting an ACM model, and it showed adaptive potential for its implementation in different health scenarios. The research generated strategies that contributed to face the challenges of the transition toward personalized medicine for chronic patients.