Purpose of review: There is increasing evidence for relevant sex differences in pathophysiology, symptom presentation and outcomes in obstructive sleep apnoea (OSA). However, research on sex differences and sex-specific phenotypes in sleep-disordered breathing (SDB) is still in its infancy and data on sex differences in other SDB is still very scarce. Recent findings: While OSA is more common in men than in premenopausal women, the prevalence of OSA doubles postmenopausally and becomes comparable to that of men. Women have a lower collapsibility of the upper airway and a lower arousal threshold. In addition, the rapid eye movement (REM)-apnoea–hypopnoea index (AHI) is typically higher in women than in men, but the non-REM-AHI and thus the total AHI is often lower. Women are often symptomatic at lower AHI and present more frequently with symptoms of sleep fragmentation and poor sleep quality. Both certain forms of OSA (e.g. REM-OSA) and certain phenotypes (e.g. COMISA) are more common in women. Men have a higher risk of high loop gain central sleep apnoea. Summary: For a better understanding of sex-typical phenotypes with the aim of a more targeted treatment approach of SDB, adequately powered studies on sex differences in SDB should be conducted.

Systemic inflammation is important in obstructive sleep apnea (OSA) pathophysiology and its comorbidity. We aimed to assess the levels of inflammatory biomarkers in a large sample of OSA patients and to investigate any correlation between these biomarkers with clinical and polysomnographic (PSG) parameters. This was a cross-sectional study in which 2983 patients who had undergone a polysomnography for OSA diagnosis were recruited. Patients with known comorbidities were excluded. Included patients (n=1053) were grouped according to apnea-hypopnea index (AHI) as mild, moderate, and severe. Patients with AHI < 5 served as controls. Demographics, PSG data, and levels of high-sensitivity C-reactive protein (hs-CRP), fibrinogen, erythrocyte sedimentation rate (ESR), and uric acid (UA) were measured and compared between groups. A significant difference was found between groups in hs-CRP, fibrinogen, and UA. All biomarkers were independently associated with OSA severity and gender (p<0.05). Females had increased levels of hs-CRP, fibrinogen, and ESR (p<0.001) compared to men. In contrast, UA levels were higher in men (p<0.001). Our results suggest that inflammatory markers significantly increase in patients with OSA without known comorbidities and correlate with OSA severity. These findings may have important implications regarding OSA diagnosis, monitoring, treatment, and prognosis. This trial is registered with ClinicalTrials.gov numberNCT03070769.

Although the prevalence of obstructive sleep apnea/hypopnea syndrome (OSAHS) is high in patients with acute coronary syndromes (ACS), there is little knowledge about the persistence of OSAHS in ACS patients after the acute event. We aimed to assess the prevalence and time course of OSAHS in patients with ACS during and after the acute cardiac event. Fifty-two patients with first-ever ACS, underwent attended overnight polysomnography (PSG) in our sleep center on the third day after the acute event. In patients with an apnea hypopnea index (AHI) > 10/h, we performed a follow up PSG 1 and 6 months later. Twenty-eight patients (54%) had an AHI > 10/h. There was a significant decrease in AHI 1 month after the acute event (13.9 vs. 19.7, p = 0.001), confirming the diagnosis of OSAHS in 22 of 28 patients (79%). At 6-month follow-up, the AHI had decreased further (7.5 vs. 19.7, p < 0.05), and at that time only 6 of the 28 patients (21%) were diagnosed as having OSAHS. Twelve of the 16 current smokers stopped smoking after the acute event. We have demonstrated a high prevalence of OSAHS in ACS patients, which did not persist 6 months later, indicating that, to some degree, OSAHS may be transient and related with the acute phase of the underlying disease or the reduction in the deleterious smoking habit.

The aim of our study was to assess university students’ sleep quality and fatigue before and during the academic exam period and identify potential associated factors. A Web-based survey was completed by 940 students of 20 different Tertiary Institutions including demographics, sleep habits, exercise, caffeine, tobacco, alcohol use, subjective sleep quality (Pittsburgh Sleep Quality Index—PSQI), and fatigue (Fatigue severity scale—FSS) at the beginning of the semester and during the examination period. During the exam period, PSQI (8.9 vs. 6.1, p < 0.001) and FSS scores (36.9 vs. 32.7, p < 0.001) were significantly elevated compared to the pre-exam period. An increase in the PSQI score was associated with age (β = 0.111, p = 0.011), presence of chronic disease (β = 0.914, p = 0.006), and depressive symptoms (β = 0.459, p = 0.001). An increase in the FSS score was associated with female gender (β = 1.658, p < 0.001), age, (β = 0.198, p = 0.010), increase in smoking (β = 1.7, p = 0.029), coffee/energy drinks consumption (β = 1.988, p < 0.001), decreased levels of physical exercise (β = 1.660, p < 0.001), and depressive symptoms (β = 2.526, p < 0.001). In conclusion, our findings indicate that exam periods have a negative impact on the sleep quality and fatigue levels of university students. Potential factors were identified that could contribute to the formulation of strategies for improved sleep quality and wellness.