Prevalence, treatment and determinants of obstructive sleep apnoea and its symptoms in a population-based French cohort.

Background: Obstructive sleep apnoea (OSA) is associated with increased morbidity and mortality. Although the disorder has been well studied in selected high-risk populations, few data exist on its prevalence in the general population. We aimed to assess the prevalence and determinants of OSA in France. Methods: Data from participants of the French population-based CONSTANCES cohort aged 18-69 years at inclusion and being treated for sleep apnoea or screened for OSA in 2017 using the Berlin Questionnaire were analysed. Weighted analyses were performed to provide recent and representative results in the general population. Results: Among 20 151 participants, the prevalence of treated sleep apnoea was 3.5% (95% CI 3.0-3.9%). The prevalence of untreated subjects with a positive Berlin Questionnaire was 18.1% (95% CI 17.3-19.2%) for a total weighted prevalence of treated sleep apnoea or high risk of OSA of 20.9% (95% CI 20.0-21.9%). Regarding prevalence of OSA symptoms, it was 37.2% (95% CI 36.1-38.3%) for severe snoring and 14.6% (95% CI 13.8-15.5%) for hypersomnolence. In multivariable logistic regression analysis, male sex, age, previous cardiovascular events, smoking, low educational level, low physical activity and depressive symptoms were associated with having either treated sleep apnoea or a positive Berlin Questionnaire. Conclusion: In this large French population-based cohort, one in five participants had a high likelihood of OSA, whereas only 3.5% were treated for the disorder, suggesting major underdiagnosis in the general population. OSA diagnosis should be considered more often in people with risk factors such as depressive symptoms as well as unhealthy behaviours and socioeconomic conditions.

Knowledge self-monitoring, efficiency, and determinants of self-confidence statement in multiple choice questions in medical students.

BACKGROUND: Multiple-choice question (MCQ) tests are commonly used to evaluate medical students, but they do not assess self-confidence nor penalize lucky guess or harmful behaviors. Based on a scoring method according to the appropriateness of confidence in answers, the study aimed at assessing knowledge self-monitoring and efficiency, and the determinants of self-confidence. METHODS: A cross-sectional study of 842 s- and third-year medical students who were asked to state their level of confidence (A: very confident, B: moderately confident and C: not confident) during 12 tests (106,806 events). A bonus was applied if the level of confidence matched with the correctness of the answer, and a penalty was applied in the case of inappropriate confidence. RESULTS: Level A was selected more appropriately by the top 20% students whereas level C was selected more appropriately by the lower 20% students. Efficiency of higher-performing students was higher when correct (among correct answers, rate of A statement), but worse when incorrect compared to the bottom 20% students (among incorrect answers, rate of C statement). B and C statements were independently associated with female and male gender, respectively (OR for male vs female = 0.89 [0.82-0.96], p = 0.004, for level B and 1.15 [1.01-1.32], p = 0.047, for level C). CONCLUSION: While both addressing the gender confidence gap, knowledge self-monitoring might improve awareness of students' knowledge whereas efficiency might evaluate appropriate behavior in clinical practice. These results suggest differential feedback during training in higher versus lower-performing students, and potentially harmful behavior in decision-making during clinical practice in higher-performing students.

Effect of oral anticoagulation on clinical outcomes and haemodynamic variables after successful transcatheter aortic valve implantation.

BACKGROUND: The effect of oral anticoagulation on clinical and haemodynamic outcomes following successful transcatheter aortic valve implantation is unclear. AIMS: To evaluate the effect of oral anticoagulation within the first year after transcatheter aortic valve implantation. METHODS: All patients undergoing transcatheter aortic valve implantation in two French tertiary centres from 2010 to 2016 were included prospectively. The composite outcome of death, stroke, readmission for heart failure or major/life-threatening bleeding according to Valve Academic Research Consortium 2 criteria within 1year was evaluated. Valvular haemodynamic deterioration was defined as mean transprosthetic gradient ≥20mmHg or an increase of ≥10mmHg during echocardiographic follow-up. RESULTS: Of the 1139 patients included, 400 (35.1%) were discharged on oral anticoagulation. The primary endpoint was more frequent in the group with versus without oral anticoagulation (29.4% vs. 17.3% 21.5%; hazard ratio 1.83, 95% confidence interval 1.42-2.35). Composite endpoint risk factors were chronic pulmonary and kidney diseases, previous atrial fibrillation, left ventricular ejection fraction ≤30% at discharge and no femoral vascular approach, but not oral anticoagulation prescription at discharge. Conversely, 58 patients were identified with valvular haemodynamic deterioration, including 11 (19%) in the group with oral anticoagulation and 47 (81%) in the group without oral anticoagulation. Valvular haemodynamic deterioration risk factors were absence of oral anticoagulation exposure, increased body mass index, use of a balloon-expandable bioprosthesis and use of a bioprosthesis with diameter ≤23mm. Antithrombotic treatment crossover (i.e. oral anticoagulation interruption or introduction during follow-up) occurred in 9.6% of patients, and was a risk factor for death (adjusted hazard ratio 3.39, 95% confidence interval 1.63-7.07). CONCLUSIONS: Baseline characteristics, rather than oral anticoagulation prescription at discharge, were associated with adverse outcomes following successful transcatheter aortic valve implantation. Conversely, oral anticoagulation was associated with reduced valvular haemodynamic deterioration.

Hyperventilation: A Possible Explanation for Long-Lasting Exercise Intolerance in Mild COVID-19 Survivors?

Since the outbreak of the coronavirus (COVID-19) pandemic, most attention has focused on containing transmission and addressing the surge of critically ill patients in acute care settings. As we enter the second phase of the pandemic, emphasis must evolve to post-acute care of COVID-19 survivors. Persisting cardiorespiratory symptoms have been reported at several months after the onset of the infection. Information is lacking on the pathophysiology of exercise intolerance after COVID-19. Previous outbreaks of coronaviruses have been associated with persistent dyspnea, muscle weakness, fatigue and reduced quality of life. The extent of Covid-19 sequelae remains to be evaluated, but persisting cardiorespiratory symptoms in COVID-19 survivors can be described as two distinct entities. The first type of post-Covid symptoms are directly related to organ injury in the acute phase, or the complications of treatment. The second type of persisting symptoms can affect patients even with mild initial disease presentation without evidence of organ damage. The mechanisms are still poorly qualified to date. There is a lack of correlation between initial symptom severity and residual symptoms at exertion. We report exercise hyperventilation as a major limiting factor in COVID-19 survivors. The origin of this hyperventilation may be related to an abnormality of ventilatory control, by either hyperactivity of activator systems (automatic and cortical ventilatory control, peripheral afferents, and sensory cortex) or failure of inhibitory systems (endorphins) in the aftermath of pulmonary infection. Hyperventilation-induced hypocapnia can cause a multitude of extremely disabling symptoms such as dyspnea, tachycardia, chest pain, fatigue, dizziness and syncope at exertion.

Incidence of, risk factors for and impact of readmission for heart failure after successful transcatheter aortic valve implantation.

BACKGROUND: The incidence of and risk factors for readmission for heart failure after successful transcatheter aortic valve implantation (TAVI) are unclear. AIMS: We sought to evaluate the incidence of, risk factors for and clinical impact of readmission for heart failure after successful TAVI in an unselected patient population. METHODS: All patients who underwent successful TAVI in two high-volume French tertiary centres from February 2010 to December 2016 were included prospectively and followed up for 1 year. A Cox multivariable model was used to assess risk factors for readmission for heart failure and mortality. RESULTS: A total of 1139 patients (mean age 82.4±7.7years; 52.2% male sex) were included. Readmission for heart failure occurred in 99 (9.2%) patients. Risk factors for readmission for heart failure were previous atrial fibrillation (adjusted hazard ratio [adjHR] 1.62, 95% confidence interval [CI] 1.09-2.40), diabetes mellitus (adjHR 1.67, 95% CI 1.11-2.50), chronic kidney disease (adjHR 1.72, 95% CI 1.13-2.62), chronic pulmonary disease (adjHR 1.81, 95% CI 1.17-2.81) and left ventricular ejection fraction after TAVI ≤ 35% (adjHR 2.12, 95% CI 1.20-3.75). Readmission for heart failure was strongly associated with mortality (adjHR 3.11, 95% CI 1.95-4.94), along with increased Society of Thoracic Surgeons' score (adjHR 1.07, 95% CI 1.03-1.12), chronic pulmonary disease (adjHR 1.45, 95% CI 1.00-2.09), previous atrial fibrillation (adjHR 2.11, 95% CI 1.52-2.93) and shock during the index hospitalization (adjHR 2.56, 95% CI 1.41-4.65). CONCLUSIONS: Readmission for heart failure occurs in one in 10 patients after successful TAVI, and is a strong risk factor for mortality. Co-morbidities and left ventricular ejection fraction after TAVI≤35% are the main risk factors for readmission for heart failure.