Association between suicidal behaviour and impaired glucose metabolism in depressive disorders

Background: Disturbances in lipid metabolism have been linked to suicidal behaviour, but little is known about the association between suicide risk and abnormal glucose metabolism in depression. Hyperglycaemia and hyperinsulinaemia may increase the risk of depression and also the risk for suicide, we therefore studied associations between suicidal behaviour and disturbances in glucose metabolism in depressive patients who had been referred to depression nurse case managers. Methods: Patients aged 35 years and older (N = 448, mean age 51 years) who were experiencing a new depressive episode, who were referred to depression nurse case managers in 2008-2009 and who scored = 10 on the Beck Depression Inventory were enrolled in this study. The study was conducted in municipalities within the Central Finland Hospital District (catchment area of 274 000 inhabitants) as part of the Finnish Depression and Metabolic Syndrome in Adults study. The patients' psychiatric diagnoses and suicidal behaviour were confirmed by the Mini-International Neuropsychiatric Interview. Blood samples, for glucose and lipid determinations, were drawn from participants after 12 h of fasting, which was followed by a 2-hour oral glucose tolerance test (OGTT) when blood was drawn at 0 and 2 h. Insulin resistance was measured by the Quantitative Insulin Sensitivity Check Index (QUICKI) method.' Results: Suicidal ideation (49 %) and previous suicide attempts (16 %) were common in patients with major depressive disorder or dysthymia. Patients with depression and suicidal behaviour had higher blood glucose concentrations at baseline and at 2 hours in the OGTT. Glucose levels associated positively with the prevalence of suicidal behaviour, and the linearity was significant at baseline (p for linearity: 0.012, adjusted for age and sex) and for 2-hour OGTT glucose (p for linearity: 0.004, adjusted for age and sex). QUICKI levels associated with suicidal behavior (p for linearity across tertiles of QUICKI: 0.026). Total and LDL cholesterol and triglyceride levels were also higher in those patients with suicidal behaviour. Multivariate analysis revealed that blood glucose levels, BDI scores and antidepressive medications associated with suicidal behaviour. Conclusion: Insulin resistance and disturbances in glucose and lipid metabolism may be more common in middle-aged depressive patients with suicidal behaviour.Peer reviewe

Self-Applied Electrode Set Provides a Clinically Feasible Solution Enabling EEG Recording in Home Sleep Apnea Testing

Home sleep apnea testing (HSAT) without electroencephalography (EEG) recording is increasingly used as an alternative to in-laboratory polysomnography for the diagnosis of obstructive sleep apnea (OSA). However, without EEG, electrooculography (EOG), and chin electromyography (EMG) recordings, the OSA severity may be significantly underestimated. Although several ambulatory EEG systems have been recently introduced, no patient-applied systems including EEG, EOG, and chin EMG suitable for home polysomnography are currently in clinical use. We have recently developed and pre-clinically tested a self-applied ambulatory electrode set (AES), consisting of frontal EEG, EOG, and EMG, in subjects with possible sleep bruxism. Now, in this clinical feasibility study, we investigated the signal scorability and usability of the AES as a self-administered sleep assessment approach supplementing the conventional HSAT device. We also investigated how the diagnostic parameters and OSA severity changed when utilizing the AES. Thirty-eight patients (61 % male, 25-78 years) with a clinical suspicion of OSA conducted a single-night, self-administered HSAT with a portable polysomnography device (Nox A1, Nox Medical, Reykjavik, Iceland) supplemented with AES. Only one AES recording failed. The use of AES signals in data analysis significantly affected the median apnea-hypopnea index (AHI), increasing it from 9.4 to 12.7 events/h (p < 0.001) compared to the conventional HSAT. Also, in eight patients, the OSA severity class changed to one class worse. Perceived ease of use was well in line with that previously found among healthy volunteers. These results suggest that the AES provides an easy, clinically feasible solution to record EEG as a part of conventional HSAT.Peer reviewe

Deep Learning Enables Accurate Automatic Sleep Staging Based on Ambulatory Forehead EEG

We have previously developed an ambulatory electrode set (AES) for the measurement of electroencephalography (EEG), electrooculography (EOG), and electromyography (EMG). The AES has been proven to be suitable for manual sleep staging and self-application in in-home polysomnography (PSG). To further facilitate the diagnostics of various sleep disorders, this study aimed to utilize a deep learning-based automated sleep staging approach for EEG signals acquired with the AES. The present neural network architecture comprises a combination of convolutional and recurrent neural networks previously shown to achieve excellent sleep scoring accuracy with a single standard EEG channel (F4-M1). In this study, the model was re-trained and tested with 135 EEG signals recorded with AES. The recordings were conducted for subjects suspected of sleep apnea or sleep bruxism. The performance of the deep learning model was evaluated with 10-fold cross-validation using manual scoring of the AES signals as a reference. The accuracy of the neural network sleep staging was 79.7% (kappa = 0.729) for five sleep stages (W, N1, N2, N3, and R), 84.1% (kappa = 0.773) for four sleep stages (W, light sleep, deep sleep, R), and 89.1% (kappa = 0.801) for three sleep stages (W, NREM, R). The utilized neural network was able to accurately determine sleep stages based on EEG channels measured with the AES. The accuracy is comparable to the inter-scorer agreement of standard EEG scorings between international sleep centers. The automatic AES-based sleep staging could potentially improve the availability of PSG studies by facilitating the arrangement of self-administrated in-home PSGs.Peer reviewe

Severity of individual obstruction events is gender dependent in sleep apnea

Purpose In obstructive sleep apnea (OSA), severity of individual obstruction events is connected to increased mortality rate and it can be significantly different in patients with similar apnea-hypopnea index (AHI). However, possible gender-dependent variation in severity of obstruction events in different OSA categories is unknown. We investigated whether the severity of obstruction events differs between genders with similar AHI and if this difference varies between OSA categories. Methods Polygraphic recordings of 2057 consecutive patients with suspected OSA were reanalyzed and those with AHI ≥5/h were included for further analysis (nmale = 893 and nfemale = 197). Statistical significance of differences in AHI, apnea index, hypopnea index, oxygen desaturation index, obstruction severity parameter, and severity of individual obstruction events between genders were evaluated using the Mann-Whitney U (MWU) test as well as the general linear model (GLM) univariate analysis adjusted for age, BMI, smoking, daytime sleepiness, snoring, and heart failure. Results Apneas were 16.9 and 19.6% longer (MWU p ≤ 0.015, GLM p ≤ 0.036) and desaturation areas were 15.4 and 23.7% larger (MWU p ≤ 0.024, GLM p ≤ 0.053) in males compared to females with moderate and severe OSA, respectively. In contrast, hypopneas were 9.1% shorter (MWU p = 0.001, GLM p ≤ 0.001) and desaturation areas were 6.0% smaller (MWU p = 0.114, GLM p = 0.025) in men with mild OSA. The apnea index was 433.3 and 313.1% higher (MWU p ≤ 0.001, GLM p ≤ 0.043) and the hypopnea index was 12.2 and 17.8% lower (MWU p ≤ 0.001, GLM p = 0.002, p = 0.083) in males with mild and moderate OSA, respectively. Conclusion As severity of individual obstruction events was significantly different in males and females, the overall severity of OSA may not be similar despite the similarity in AHI

Supplementary information files for article: 'Intrapersonal emotional responses to the inquiry and advocacy modes of interaction: a psychophysiological study'

Supplementary information files for article: 'Intrapersonal emotional responses to the inquiry and advocacy modes of interaction: a psychophysiological study'.Abstract:In negotiations and group decision making we can use two characteristically different interaction modes: inquiry and advocacy. Inquiry refers to an interested and explorative interaction mode, and advocacy to an assertive and narrow mode. Although these modes have been studied in organizational behavior literature, the intrapersonal emotional responses to the inquiry and advocacy modes remain yet unexplored. We explored intrapersonal emotions by facial electromyography and skin conductance responses and by emotional empathy self-reports. The subjects were prompted to adopt the two modes in hypothetical encounters with another person. We found that Duchenne smiles were specific to the inquiry mode, that emotional arousal showed specificity to the expressions, and that emotional empathy predicts expressiveness in the inquiry treatment. We discuss the implications of these results to the use of the interaction modes and the related possibilities of influencing group interaction by influencing one’s own internal emotional state in group decisions.</div

Required CPAP usage time to normalize AHI in obstructive sleep apnea patients: a simulation study

Objective: Adherence to continuous positive airway pressure (CPAP) is often limited. The aim of the current work was to create a simulation tool to enable determination of the individual CPAP therapy time required to normalize apnea-hypopnea index (AHI) (< 5 events h(-1)) in a cohort of OSA patients. Approach: Polygraphic studies of 1989 consecutive patients were analyzed. CPAP therapy was simulated in 5 min intervals starting from the beginning of the night and continuing until the end. In simulation, events inside the simulated CPAP therapy periods were considered to be prevented. The cutoff points where AHI reached a normal level of < 5 events h(-1) were determined for mild, moderate and severe OSA categories. Main results: The median values of the required simulated CPAP usage times to normalize the AHI values were 3.3 h, 5.6 h and 6.5 h in the mild, moderate and severe OSA categories, respectively. However, there were great differences between individuals in the CPAP usage times required to normalize AHI. Significance: An arbitrary threshold for CPAP adherence (e.g. 4 h) leaves many OSA patients with a significant residual AHI, which could explain why some clinical trials fail to show significant benefits. Thresholds for adherence should be adjusted based on the patient-specific distribution of obstruction events during the night

Heme oxygenase-1 repeat polymorphism in septic acute kidney injury

Abstract Acute kidney injury (AKI) is a syndrome that frequently affects the critically ill. Recently, an increased number of dinucleotide repeats in the HMOX1 gene were reported to associate with development of AKI in cardiac surgery. We aimed to test the replicability of this finding in a Finnish cohort of critically ill septic patients. This multicenter study was part of the national FINNAKI study. We genotyped 300 patients with severe AKI (KDIGO 2 or 3) and 353 controls without AKI (KDIGO 0) for the guanine–thymine (GTn) repeat in the promoter region of the HMOX1 gene. The allele calling was based on the number of repeats, the cut off being 27 repeats in the S–L (short to long) classification, and 27 and 34 repeats for the S–M–L₂ (short to medium to very long) classification. The plasma concentrations of heme oxygenase-1 (HO-1) enzyme were measured on admission. The allele distribution in our patients was similar to that published previously, with peaks at 23 and 30 repeats. The S-allele increases AKI risk. An adjusted OR was 1.30 for each S-allele in an additive genetic model (95% CI 1.01–1.66; p = 0.041). Alleles with a repeat number greater than 34 were significantly associated with lower HO-1 concentration (p&lt;0.001). In septic patients, we report an association between a short repeat in HMOX1 and AKI risk