Rationale: It is currently unclear which patients with obstructive sleep apnea (OSA) are at increased cardiovascular risk. Objective: To investigate the value of pulse wave amplitude drops (PWADs), reflecting sympathetic activations and vasoreactivity, as a biomarker of cardiovascular risk in OSA. Methods: PWADs were derived from pulse oximetry–based photoplethysmography signals in three prospective cohorts: HypnoLaus (N = 1,941), the Pays-de-la-Loire Sleep Cohort (PLSC; N = 6,367), and “Impact of Sleep Apnea syndrome in the evolution of Acute Coronary syndrome. Effect of intervention with CPAP” (ISAACC) (N = 692). The PWAD index was the number of PWADs (>30%) per hour during sleep. All participants were divided into subgroups according to the presence or absence of OSA (defined as ≥15 or more events per hour or <15/h, respectively, on the apnea–hypopnea index) and the median PWAD index. Primary outcome was the incidence of composite cardiovascular events. Measurements and Main Results: Using Cox models adjusted for cardiovascular risk factors (hazard ratio; HR [95% confidence interval]), patients with a low PWAD index and OSA had a higher incidence of cardiovascular events compared with the high-PWAD and OSA group and those without OSA in the HypnoLaus cohort (HR, 2.16 [1.07–4.34], P = 0.031; and 2.35 [1.12–4.93], P = 0.024) and in the PLSC (1.36 [1.13–1.63], P = 0.001; and 1.44 [1.06–1.94], P = 0.019), respectively. In the ISAACC cohort, the low-PWAD and OSA untreated group had a higher cardiovascular event recurrence rate than that of the no-OSA group (2.03 [1.08–3.81], P = 0.028). In the PLSC and HypnoLaus cohorts, every increase of 10 events per hour in the continuous PWAD index was negatively associated with incident cardiovascular events exclusively in patients with OSA (HR, 0.85 [0.73–0.99], P = 0.031; and HR, 0.91 [0.86–0.96], P < 0.001, respectively). This association was not significant in the no-OSA group and the ISAACC cohort. Conclusions: In patients with OSA, a low PWAD index reflecting poor autonomic and vascular reactivity was independently associated with a higher cardiovascular risk.

Background: The relationship between obstructive sleep apnoea (OSA) and cognitive decline remains controversial, especially in the elderly population. We used data from the HypnoLaus study to assess associations between OSA and longitudinal cognitive changes in a sample of community-dwelling elderly individuals.Methods: We studied associations between polysomnographic OSA parameters (of breathing/hypoxaemia and sleep fragmentation) and cognitive changes over a 5-year period, after adjustment for potential confounders. The primary outcome was the annual change in cognitive scores. The moderating effects of age, sex and apolipoprotein E4 (ApoE4) status were also examined.Results: 358 elderly individuals without dementia were included (mean±sdage 71.0±4.2 years; 42.5% males). A lower mean peripheral oxygen saturation (SpO₂) during sleep was associated with a steeper decline in Mini-Mental State Examination (B= −0.12, p=0.004), Stroop test condition 1 (B=0.53, p=0.002) and Free and Cued Selective Reminding Test delayed free recall (B= −0.05, p=0.008). A longer time spent asleep withSpO₂<90% was associated with a steeper decline in Stroop test condition 1 (B=0.47, p=0.006). Moderation analysis showed that apnoea–hypopnoea index and oxygen desaturation index were associated with a steeper decline in global cognitive function, processing speed and executive function only in older participants, men and ApoE4 carriers.Conclusions: Our results provide evidence of the contribution of OSA and nocturnal hypoxaemia to cognitive decline in the elderly population.

Background and Aims: Evidence on the link between sleep patterns and cardiovascular diseases (CVDs) in the community essentially relies on studies that investigated one single sleep pattern at one point in time. This study examined the joint effect of five sleep patterns at two time points with incident CVD events. Methods: By combining the data from two prospective studies, the Paris Prospective Study III (Paris, France) and the CoLaus|PsyCoLaus study (Lausanne, Switzerland), a healthy sleep score (HSS, range 0–5) combining five sleep patterns (early chronotype, sleep duration of 7–8 h/day, never/rarely insomnia, no sleep apnoea, and no excessive daytime sleepiness) was calculated at baseline and follow-up. Results: The study sample included 11 347 CVD-free participants aged 53–64 years (44.6% women). During a median follow-up of 8.9 years [interquartile range (IQR): 8.0–10.0], 499 first CVD events occurred (339 coronary heart disease (CHD) and 175 stroke). In multivariate Cox analysis, the risk of CVD decreased by 18% [hazard ratio (HR) 0.82, 95% confidence interval (CI) 0.76–0.89] per one-point increment in the HSS. After a median follow-up of 6.0 years (IQR: 4.0–8.0) after the second follow-up, 262 first CVD events occurred including 194 CHD and 72 stroke. After adjusting for baseline HSS and covariates, the risk of CVD decreased by 16% (HR 0.84, 95% CI 0.73–0.97) per unit higher in the follow-up HSS over 2–5 years. Conclusions: Higher HSS and HSS improvement over time are associated with a lower risk of CHD and stroke in the community.

Insomnia and its opposite hypersomnia are part of the diagnostic criteria for major depressive disorder (MDD). However, no study has investigated whether the postulated sleep alterations in clinical subtypes of MDD are reflected in polysomnography (PSG)-derived objective sleep measures. The objective of this study was to establish associations between the melancholic, atypical and unspecified subtypes of MDD and objective PSG-based sleep features. This cross-sectional analysis included 1820 community-dwelling individuals who underwent PSG and a semi-structured psychiatric interview to elicit diagnostic criteria for MDD and its subtypes. Adjusted robust linear regression was used to assess associations between MDD subtypes and PSG-derived objective sleep measures. Current melancholic MDD was significantly associated with decreased absolute delta power and sleep efficiency and with increased wake after sleep onset. Remitted unspecified MDD was significantly associated with increased rapid eye movements density. No other significant associations were identified. Our findings reflect that some PSG-based sleep features differed in MDD subtypes compared with no MDD. The largest number of significant differences were observed for current melancholic MDD, whereas only rapid eye movements density could represent a risk factor for MDD as it was the only sleep measure that was also associated with MDD in remitted participants.

Background: Sleep apnoea-specific heart rate response (ΔHR) has been identified as a promising biomarker for stratifying cardiovascular (CV) risk and predicting positive airway pressure (PAP) benefit in obstructive sleep apnoea (OSA). However, the need for prior manual scoring of respiratory events potentially limits the accessibility and reproducibility of ΔHR. We aimed to evaluate the association of pulse rate response to oxygen desaturations automatically derived from pulse oximetry (ΔHR_oxi) with CV risk in OSA.Methods: ΔHR_oxiand ΔHR were measured in OSA patients from the Institut de Recherche en Santé Respiratoire Pays de la Loire Sleep Cohort (PLSC; n=5002) and the HypnoLaus cohort (n=1307). The primary outcome was major adverse CV events (MACEs), a composite of mortality, stroke and cardiac diseases. Cox regression analyses were conducted to evaluate the association of ΔHR_oxiand ΔHR, categorised into low, midrange and high categories, with MACEs.Results: MACEs occurred in 768 patients from PLSC and 87 patients from HypnoLaus (median follow-up 8.0 and 7.5 years, respectively). Multivariable Cox models showed that subjects with high ΔHR_oxi(versusmidrange) had higher risk of MACEs in PLSC (hazard ratio (HR) 1.42, 95% CI 1.18–1.71) and HypnoLaus (HR 1.72, 95% CI 1.03–2.87). Similar findings were observed for high ΔHR. Among 2718 patients from PLSC treated with PAP, the association of PAP adherence (PAP use ≥4 h·night⁻¹versusnon-adherent) with MACEs was modified by baseline ΔHR and ΔHR_oxi(p_interaction<0.05).Conclusion: ΔHR_oxicould constitute a reliable and easy to measure biomarker for stratifying CV risk and predicting CV benefit of PAP in OSA.