Rise in nocturnal respiratory rate during CPAP may be an early sign of COVID-19 in patients with obstructive sleep apnea.

None: A middle-aged man with obstructive sleep apnea who had been treated with continuous positive airway pressure developed COVID-19. An analysis of airflow records from the continuous positive airway pressure machine revealed a rise in his respiratory rate on the night before the onset of COVID-19-related symptoms, while his nocturnal respiratory rate had been stable during the 18-month period prior to the presently reported episode. The present case suggests that a rise in respiratory rate detected using continuous positive airway pressure machine data could be an important sign of impending acute illness, such as COVID-19. Studies to elucidate the usefulness of this method are warranted.

Tracheal Sound Analysis Using a Deep Neural Network to Detect Sleep Apnea.

STUDY OBJECTIVES: Portable devices for home sleep apnea testing are often limited by their inability to discriminate sleep/wake status, possibly resulting in underestimations. Tracheal sound (TS), which can be visualized as a spectrogram, carries information about apnea/hypopnea and sleep/wake status. We hypothesized that image analysis of all-night TS recordings by a deep neural network (DNN) would be capable of detecting breathing events and classifying sleep/wake status. The aim of this study is to develop a DNN-based system for sleep apnea testing and validate it using a large sampling of polysomnography (PSG) data. METHODS: PSG examinations for the evaluation of sleep-disordered breathing (SDB) were performed for 1,852 patients: 1,548 PSG records were used to develop the system, and the remaining 304 records were used for validation. TS spectrogram images were obtained every 60 seconds and labeled with the PSG scoring results (breathing event and sleep/wake status), then introduced to DNN learning. Two different DNNs were trained for breathing status and sleep/wake status, respectively. RESULTS: A DNN with convolutional layers showed the best performance for discriminating breathing status. The same DNN structure was trained for sleep/wake discrimination. In the validation study, the DNN analysis was capable of discriminating the sleep/wake status with reasonable accuracy. The diagnostic sensitivity, specificity, and area under the receiver operating characteristic curves for diagnosis of SDB with apnea-hypopnea index of > 5, 15, and 30 were 0.98, 0.76, and 0.99; 0.97, 0.90, and 0.99; and 0.92, 0.94, and 0.98, respectively. CONCLUSIONS: The developed system using the TS DNN analysis has a good performance for SDB testing. CITATION: Nakano H, Furukawa T, Tanigawa T. Tracheal sound analysis using a deep neural network to detect sleep apnea. J Clin Sleep Med. 2019;15(8): 1125-1133.

Predictors of successful long-term weight loss maintenance: a two-year follow-up.

BACKGROUND: Weight regain is a common problem following weight loss intervention, with most people who seek treatment for obesity able to lose weight, but few able to sustain the changes in behavior required to prevent subsequent weight regain. The identification of factors that predict which patients will successfully maintain weight loss or who are at risk of weight regain after weight loss intervention is necessary to improve the current weight maintenance strategies. The aim of the present study is identify factors associated with successful weight loss maintenance by women with overweight or obesity who completed group cognitive behavioral treatment (CBT) for weight loss. METHODS: Ninety women with overweight or obesity completed a 7-month weight loss intervention. The data of 86 who completed follow-up surveys 12 and 24 months after the end of the treatment was analyzed. Depression, anxiety, binge eating, food addiction, and eating behaviors were assessed before and after the weight loss intervention. Participants who lost at least 10% of their initial weight during the weight loss intervention and had maintained the loss at the month 24 follow-up were defined as successful. RESULTS: The intervention was successful for 27 participants (31.3%) and unsuccessful for 59 (68.6%). Multiple logistic regression analysis extracted larger weight reduction during the weight loss intervention, a lower disinhibition score, and a low food addiction score at the end of the weight loss intervention as associated with successful weight loss maintenance. CONCLUSION: The results suggest that larger weight reduction during the weight loss intervention and lower levels of disinhibition and food addiction at the end of the weight loss intervention predicted successful weight loss maintenance. TRIAL REGISTRATION: Trial registry name: Development and validation of effective treatments of weight loss and weight-loss maintenance using cognitive behavioral therapy for obese patients. Registration ID: UMIN000006803 Registered 1 January 2012. URL: https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000008052.

The Relationship between Snoring Sound Intensity and Morning Blood Pressure in Workers.

STUDY OBJECTIVES: This study aimed to determine the consequences of snoring independent of obstructive sleep apnea (OSA) and hypothesized that snoring sound intensity, as assessed by mean tracheal sound (TS) energy (Leq), is related to morning blood pressure (BP). METHODS: A home-based TS monitoring study was performed for two nights on 191 workers in Japan using an IC recorder. Leq and the respiratory disturbance index (RDI) were calculated from the TS data. RDI was used as a marker of OSA severity. Systolic and diastolic BP measurements in the evening and morning (eSBP/eDBP and mSBP/mDBP, respectively) were done before and after TS recording. The data of the second night were analyzed. RESULTS: Leq was significantly related to both mSBP and mDBP (r = 0.32, p < 0.0001; r = 0.34, p < 0.0001, respectively). Leq was also significantly related to morning BP after adjustment for age, sex, and body mass index. However, the relationship was no longer significant when both RDI and Leq were included in the multiple regression model. In non-apneic, non-obese subjects, Leq was significantly related to both mSBP and mDBP (r = 0.38, p < 0.0001; r = 0.33, p = 0.0004, respectively). In this group, Leq was associated with mSBP after adjusting for all confounding factors (n = 106, p = 0.022). CONCLUSIONS: The association between night TS intensity and morning BP suggests a pathological role of heavy snoring. To understand this association, a prospective cohort study in a general population is warranted. COMMENTARY: A commentary on this article appears in this issue on page 1581.

Predictors of Dropout by Female Obese Patients Treated with a Group Cognitive Behavioral Therapy to Promote Weight Loss.

OBJECTIVE: To investigate predictors of dropout from a group cognitive behavioral therapy (CBT) intervention for overweight or obese women. METHODS: 119 overweight and obese Japanese women aged 25-65 years who attended an outpatient weight loss intervention were followed throughout the 7-month weight loss phase. Somatic characteristics, socioeconomic status, obesity-related diseases, diet and exercise habits, and psychological variables (depression, anxiety, self-esteem, alexithymia, parenting style, perfectionism, and eating attitude) were assessed at baseline. Significant variables, extracted by univariate statistical analysis, were then used as independent variables in a stepwise multiple logistic regression analysis with dropout as the dependent variable. RESULTS: 90 participants completed the weight loss phase, giving a dropout rate of 24.4%. The multiple logistic regression analysis demonstrated that compared to completers the dropouts had significantly stronger body shape concern, tended to not have jobs, perceived their mothers to be less caring, and were more disorganized in temperament. Of all these factors, the best predictor of dropout was shape concern. CONCLUSION: Shape concern, job condition, parenting care, and organization predicted dropout from the group CBT weight loss intervention for overweight or obese Japanese women.

Relationship between snoring sound intensity and sleepiness in patients with obstructive sleep apnea.

STUDY OBJECTIVES: Subjectively assessed snoring and sleepiness are known to be related. However, no evidence supporting the usefulness of snoring measurements exists. We examined whether the objectively measured snoring intensity was correlated with sleepiness. METHODS: The records of 515 patients who underwent polysomnography for suspected obstructive sleep apnea were retrospectively reviewed. Subjective sleepiness was assessed using the Epworth sleepiness scale (ESS). Snoring intensity was assessed using the highest one percentile ambient sound pressure level (L1) attained while asleep during polysomnography. RESULTS: L1 was correlated with ESS in apneic patients with an apnea-hypopnea index (AHI) > or =15 (r = 0.38, p <0.0001), but not in other patients. The correlation in the apneic patients was preserved after adjustments for various confounding factors, including the AHI. A step-wise multiple regression in the apneic patients adopted desaturation time, L1, daily sleep time, subjective snoring, and nasal obstruction symptoms as determinants for the ESS. L1 was correlated with the mean pulse rate during polysomnography but not with sleep fragmentation variables after adjustment for the AHI. CONCLUSIONS: The measured snoring intensity was independently related to sleepiness in apneics. Snoring intensity may explain part of sleepiness that cannot be fully explained by ordinary polysomnographic variables.

[A case of inflammatory granuloma secondary to a foreign body (Cryptomeria) mimicking a bronchial tumor].

This report documents a case of inflammatory granuloma overcoming secondary to a foreign body (Cryptomeria) mimicking a bronchial tumor. A 45-year-old man was referred to the hospital because of hemoptysis and a chronic cough. He had had a chronic cough before visiting the hospital, but had left it untreated for months. A computed tomography (CT) scan showed bronchiectasis in the right lower lobe with evidence of mediastinal lymphadenopathy. Fiberoptic bronchoscopic examinations revealed a tumor with an uneven surface at the orifice of the right B10(b+c), bronchus. The cytological findings of the bronchial tumor showed no malignancy but a predominance of neutrophils. Antibiotics were administered intravenously because of a suspected respiratory infection. After treatment, the abnormal shadows on the chest CT improved. Fiberoptic bronchoscopic examinations showed the bronchial tumor to have disappeared, and a bronchial foreign body was found lodged in the right. B10(b+c) bronchus and it was removed. Pathological examinations and a detailed history revealed that the patient had aspirated a foreign body (Cryptomeria). The tumor was thought to be an inflammatory granuloma secondary to the aspiration of the foreign body. This case highlights the need to search aggressively for foreign bodies in case of clinical symptoms, such as chronic cough, hemoptysis, or findings such as respiratory infection, and bronchial occlusion.