Differences in Polysomnographic and Craniofacial Characteristics of Catathrenia Phenotypes: A Cluster Analysis.

Purpose: Catathrenia is a rare sleeping disorder characterized by repetitive nocturnal groaning during prolonged expirations. Patients with catathrenia had heterogeneous polysomnographic, comorbidity, craniofacial characteristics, and responses to treatment. Identifying phenotypes of catathrenia might benefit the exploration of etiology and personalized therapy. Patients and Methods: Sixty-six patients diagnosed with catathrenia by full-night audio/video polysomnography seeking treatment with mandibular advancement devices (MAD) or continuous positive airway pressure (CPAP) were included in the cohort. Polysomnographic characteristics including sleep architecture, respiratory, groaning, and arousal events were analyzed. Three-dimensional (3D) and 2D craniofacial hard tissue and upper airway structures were evaluated with cone-beam computed tomography and lateral cephalometry. Phenotypes of catathrenia were identified by K-mean cluster analysis, and inter-group comparisons were assessed. Results: Two distinct clusters of catathrenia were identified: cluster 1 (n=17) was characterized to have more males (71%), a longer average duration of groaning events (18.5±4.8 and 12.8±5.7s, p=0.005), and broader upper airway (volume 41,386±10,543 and 26,661±6700 mm3, p<0.001); cluster 2 (n=49) was characterized to have more females (73%), higher respiratory disturbance index (RDI) (median 1.0 [0.3, 2.0] and 5.2 [1.2, 13.3]/h, p=0.009), more respiratory effort-related arousals (RERA)(1 [1, 109] and 32 [13, 57)], p=0.005), smaller upper airway (cross-sectional area of velopharynx 512±87 and 339±84 mm2, p<0.001) and better response to treatment (41.2% and 82.6%, p=0.004). Conclusion: Two distinct phenotypes were identified in patients with catathrenia, primary catathrenia, and catathrenia associated with upper airway obstruction, suggesting respiratory events and upper airway structures might be related to the etiology of catathrenia, with implications for its treatment.

The month of birth has a seasonal effect in Chinese patients with narcolepsy and cataplexy.

STUDY OBJECTIVES: We assessed the yearly seasonal, environmental effects on birth pattern in Chinese patients later diagnosed with narcolepsy and cataplexy and explored if this effect persisted in patients with symptoms onset date before, following, and after the 2009 H1N1 pandemic. METHODS: A total of 1,942 patients with birth data information and diagnosed narcolepsy with cataplexy were included in this study. The birth month and seasonal effect of 1,064 patients born from 1970 to 2000 were compared to controls (n = 2,028,714) from the general population. Furthermore, birth season effect in 1,373 patients with definite disease onset month were compared among patients with onset date before (n = 595), following (from January 2010 to December 2010) (n = 325), and after (n = 453) the H1N1 pandemic. RESULTS: Patients with narcolepsy and cataplexy had a significantly different seasonality from the general population (P = .027). The monthly distribution of birth month yielded a peak in November (odds ratio = 1.23 [95% confidence interval, 1.01-1.49], P = .042) and a trough in April (odds ratio = 0.68 [95% confidence interval, 0.52-0.88], P = .004). No significant difference was observed in the birth month across patients with symptom onset dates before, following, and after the 2009 H1N1 pandemic (P = .603). CONCLUSIONS: This finding across many years of seasonal effect in Chinese narcolepsy cataplexy supports a role for early-life environmental influences on disease development. CITATION: Guo J, Xu L, Wang J, et al. The month of birth has a seasonal effect in Chinese patients with narcolepsy and cataplexy. J Clin Sleep Med. 2022;18(2):461-467.

Mandibular advancement device as treatment trial for catathrenia (nocturnal groaning).

STUDY OBJECTIVES: Catathrenia is a rare disease, classified as isolated symptoms and normal variants under sleep-related breathing disorders in the International Classification of Sleep Disorders, third edition. Because of its rarity, the research on its pathogenesis and treatment is insufficient. This study aimed to evaluate whether the mandibular advancement device (MAD) could be considered an alternative treatment trial and if so, to explore factors predicting its effectiveness. METHODS: Thirty patients (12 men and 18 women, aged 16-67 years) with catathrenia participated in the study. They underwent standard clinical evaluation, questionnaires, physical examinations, craniofacial evaluations, video polysomnography, and imaging of the upper airway before and after the insertion of the MAD. The groaning index (groaning episodes per hour of sleep) and apnea-hypopnea index were evaluated, and anatomic factors predicting effectiveness were explored. RESULTS: The sleep efficiency of most patients was higher than 80%, and groaning was present throughout all stages of sleep. With the insertion of the MAD, the groaning index decreased significantly from 5.8 (2.7-14.3) to 2.8 (1.3-12.2) events/h (P = .014). Age had a negative effect on efficacy. Mandibular repositioning of the MAD, especially the amount of vertical opening and changes of the cross-sectional area of the hypopharynx, was positively related with efficacy. CONCLUSIONS: The MAD could be considered a possible treatment trial for those seeking treatment for groaning. CLINICAL TRIAL REGISTRATION: Registry: Chinese Clinical Trial Register; Name: The etiology of catathrenia based on oral and maxillofacial system; URL: http://www.chictr.org.cn/showproj.aspx?proj=22286; Identifier: ChiCTR-COC-17013239. CITATION: Yu M, Hao Z, Xu L, Wen Y, Han F, Gao X. Mandibular advancement device as treatment trial for catathrenia (nocturnal groaning). J Clin Sleep Med. 2021;17(9):1767-1776.

Polysomnographic characteristics and acoustic analysis of catathrenia (nocturnal groaning).

OBJECTIVE: Catathrenia is a sleep disorder characterized by nocturnal groaning sounds emitted during prolonged expiration. As a rare condition, its polysomnographic findings were inconsistent. We aimed to present polysomnographic characteristics of catathrenia patients and perform acoustic analysis of groaning sounds. APPROACH: Twenty-three patients (eight males and 15 females) diagnosed with catathrenia by video-polysomnography were included. They underwent clinical evaluation and physical examination, and answered a questionnaire. Acoustic analyses (oscillograms and spectrograms) of catathrenia and snoring signals were performed by Praat 6.1.09. Sounds were classified according to Yanagihara criteria. MAIN RESULTS: The average age of catathrenia patients was 29.6 ± 10.0 years, with a body mass index of 22.3 ± 5.1 kg m-2. A total of 3728 groaning episodes were documented. Catathrenia events of 16 patients (70%) were rapid eye movement (REM)-predominant. The average duration of groaning was 11.4 ± 4.6 s, ranging from 1.3 to 74.9 s. All signals of groaning were rhythmic or semi-rhythmic, classified as type I and type II, respectively, with formants and harmonics. Snoring events were observed in nine patients. Snoring mainly occurred in the non-REM stage, with a duration of less than 1.5 s. Signals of snoring were chaotic, classified as type III, without harmonics. SIGNIFICANCE: Catathrenia occurred in all sleep stages but mainly in REM. Durations of groaning varied greatly across patients. Acoustic characteristics of catathrenia were typical. Groaning had rhythmic or semi-rhythmic waveform, formants and harmonics, indicating vocal origin, while snoring had chaotic waveform.

[Cardiac functional alterations and its risk factors in elderly patients with obstructive sleep apnea syndrome free of cardiovascular disease].

OBJECTIVE: To evaluate the changes of cardiac structure and function and their risk factors in elderly patients with obstructive sleep apnea syndrome (OSA) without cardiovascular complications. METHODS: Eighty-two elderly OSA patients without cardiovascular disease admitted between January, 2015 and October, 2016 were enrolled in this study. According to their apnea-hypopnea index (AHI, calculated as the average number of episodes of apnoea and hypopnoea per hour of sleep), the patients were divided into mild OSA group (AHI < 15) and moderate to severe OSA group (AHI ≥ 15). The demographic data and the general clinical data were recorded and fasting blood samples were collected from the patients on the next morning following polysomnographic monitoring for blood cell analysis and biochemical examination. Echocardiography was performed within one week after overnight polysomnography, and the cardiac structure, cardiac function and biochemical indexes were compared between the two groups. RESULTS: Compared with those with mild OSA group, the patients with moderate to severe OSA had significantly higher hematocrit (0.22±0.08 vs 0.17±0.04, P=0.032) and serum creatinine level (70.94± 27.88 vs 54.49±34.22 µmol/L, P=0.022). The left ventricular ejection fraction, interventricular septal thickness, left ventricular posterior wall thickness, left atrial diameter and left ventricular end-diastolic diameter were all similar between the two groups. With a similar early diastolic mitral flow velocity (E) between the two groups, the patients with moderate to severe OSA had a significantly higher late diastolic mitral flow velocity (A) (70.35±6.87 vs 64.09±8.31, P=0.0001) and a significantly lower E/A ratio (0.98±0.06 vs 1.08±0.05, P=0.0001) than the patients with mild OSA. Multiple linear regression showed that the E/A ratio was negatively correlated with AHI (ß =- 0.645, P=0.0001). CONCLUSIONS: Cardiac diastolic function impairment may occur in elderly patients with moderate or severe OSA who do not have hypertension or other cardiovascular diseases, and the severity of the impairment is positively correlated with AHI.