Obstructive sleep apnea and cognitive functioning in the older general population: The moderating effect of age, sex, ApoE4, and obesity.

Research on the relationship between obstructive sleep apnea and cognitive functioning has yielded conflicting results, particularly in the older population, and moderators of this association have rarely been studied. Here we investigated the cross-sectional association between obstructive sleep apnea and cognitive functioning as well as the moderating effect of age, sex, apolipoprotein E4, and obesity on this association among community-dwelling older people. We analysed data from 496 participants (71.4 ± 4.4 years; 45.6% men) of the HypnoLaus study who underwent polysomnography and a battery of neuropsychological tests. The sample was categorised as no-to-mild obstructive sleep apnea (apnea-hypopnea index 0-14.9/h; reference), moderate obstructive sleep apnea (apnea-hypopnea index 15.0-29.9/h), or severe obstructive sleep apnea (apnea-hypopnea index ≥30/h). Regression and moderation analyses were performed with adjustment for confounders. Apolipoprotein E4 and obesity moderated the association between severe obstructive sleep apnea and processing speed, whereas no moderating effects were found for age and sex. In apolipoprotein E4 carriers only, severe obstructive sleep apnea was associated with lower performance in Stroop condition 1 (B = 3.13, p = 0.024). In obese participants only, severe obstructive sleep apnea was associated with lower performance in Stroop condition 1 (B = 3.02, p = 0.025) and Stroop condition 2 (B = 3.30, p = 0.034). Severe obstructive sleep apnea was also associated with lower executive function in the whole sample according to Stroop condition 3 (B = 3.44, p = 0.020) and Stroop interference score (B = 0.24, p = 0.006). Our findings support associations of severe obstructive sleep apnea (but not moderate obstructive sleep apnea) with lower performance in processing speed and executive function in the older general population. Apolipoprotein E4 and obesity appear to be vulnerability factors that strengthen the association between severe obstructive sleep apnea and lower performance in processing speed.

Impact of spinal versus general anaesthesia on perioperative obstructive sleep apnoea severity in patients undergoing hip arthroplasty: a post hoc analysis of two randomised controlled trials.

BACKGROUND: Recommendations suggest favouring regional over general anaesthesia to reduce impact on postoperative sleep apnoea severity, but there is currently no evidence to support this. We compared the impact of general vs spinal anaesthesia on postoperative sleep apnoea severity and assessed the evolution of sleep apnoea severity up to the third postoperative night. METHODS: This post hoc analysis used pooled data from two previous randomised controlled trials in patients undergoing total hip arthroplasty under general or spinal anaesthesia (n=96), without performing a preliminary power analysis. All participants underwent respiratory polygraphy before surgery and on the first and third postoperative nights. The primary outcomes were the supine apnoea-hypopnea index on the first postoperative night and the evolution of the supine apnoea-hypopnea index up to the third postoperative night. Secondary outcomes included the oxygen desaturation index on the first and third postoperative nights. RESULTS: In the general and spinal anaesthesia groups, mean (95% confidence interval) values for the supine apnoea-hypopnoea index on the first postoperative night were 20 (16-25) and 21 (16-26) events h-1 (P=0.82), respectively; corresponding values on the third postoperative night were 34 (22-45) and 35 (20-49) events h-1 (P=0.91). The generalised estimating equations model showed a significant time effect. Secondary outcomes were similar in the two groups. CONCLUSIONS: Use of spinal anaesthesia compared with general anaesthesia was not associated with a reduction in postoperative sleep apnoea severity, which was worse on the third postoperative night. CLINICAL TRIAL REGISTRATION: NCT02717780 and NCT02566226.

Pulse Wave Amplitude Drops Index: A Biomarker of Cardiovascular Risk in Obstructive Sleep Apnea.

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.

Intrathecal morphine and sleep apnoea severity in patients undergoing hip arthroplasty: a randomised, controlled, triple-blinded trial.

BACKGROUND: Intrathecal morphine prolongs analgesia after surgery, but has been implicated in postoperative respiratory depression or apnoeic episodes. However, this has not been investigated in a prospective trial using respiratory polygraphy. This randomised controlled triple-blinded trial tested the hypothesis that intrathecal morphine increases sleep apnoea severity, measured using respiratory polygraphy. METHODS: Sixty subjects undergoing hip arthroplasty under spinal anaesthesia received either 15 mg isobaric bupivacaine 0.5% with 0.5 ml normal saline 0.9% (control group) or 15 mg isobaric bupivacaine 0.5% with 0.5 ml intrathecal morphine 100 µg (intrathecal morphine group). Respiratory polygraphy was performed before surgery and on the first and third postoperative nights. The primary outcome was the apnoea-hypopnoea index in the supine position (supine AHI) on the first postoperative night. Secondary outcomes included supine AHI on the third postoperative night, oxygen desaturation index (ODI), and ventilatory frequency during the first and third postoperative nights. RESULTS: On the first postoperative night, mean (95% confidence interval) values for supine AHI were 20.6 (13.9-27.3) and 21.2 (12.4-30.0) events h-1 in the control and intrathecal morphine groups, respectively (P=0.90). There were no significant between-group differences for any of the secondary outcomes, except for a significantly higher central and mixed apnoea index preoperatively and significantly lower mean SpO2 on the third postoperative night in the control group. CONCLUSIONS: Intrathecal morphine did not increase sleep apnoea severity when measured using respiratory polygraphy. Of note, all patients had an increased number of apnoeic episodes on the third postoperative night. CLINICAL TRIAL REGISTRATION: NCT02566226.

Night work and prostate cancer risk: results from the EPICAP Study.

OBJECTIVE: To investigate the role of night work in prostate cancer based on data from the EPICAP Study. METHODS: EPICAP is a French population-based case-control study including 818 incident prostate cancer cases and 875 frequency-matched controls that have been interviewed face to face on several potential risk factors including lifetime occupational history. Detailed information on work schedules for each job (permanent or rotating night work, duration, total number of nights, length of the shift, number of consecutive nights) as well as sleep duration and chronotype, was gathered. Prostate cancer aggressiveness was assessed by Gleason Score. RESULTS: Night work was not associated with prostate cancer, whatever the aggressiveness of prostate cancer, while we observed an overall increased risk among men with an evening chronotype (OR=1.83, 95% CI 1.05 to 3.19). A long duration of at least 20 years of permanent night work was associated with aggressive prostate cancer (OR=1.76, 95% CI 1.13 to 2.75), even more pronounced in combination with a shift length >10 hours or ≥ 6 consecutive nights (OR=4.64, 95% CI 1.78 to 12.13; OR=2.43, 95% CI 1.32 to 4.47, respectively). CONCLUSION: Overall, ever night work, either permanent or rotating, was not associated to prostate cancer. Nevertheless, our results suggest that a long duration of permanent night work in combination with a long shift length or at least six consecutive nights may be associated with prostate cancer, particularly with aggressive prostate cancer. Further studies are needed to confirm those findings.

Sex-specific associations of different anthropometric indices with acute and chronic insomnia.

Background: Sleep disorders, including insomnia, are risk factors for weight gain. However, few epidemiological studies have investigated the association of anthropometric markers with insomnia as an outcome. Methods: In this observational, cross-sectional study, we assessed the association of 3 different anthropometric indices with acute and chronic insomnia. We used data from 13 389 French adults (mean age= 51.9 ± 13.1 years; 70.3% women) enrolled in the NutriNet-Santé-Biobank cohort. Body weight, height, waist and hip circumference were measured once during a clinic visit (2011-14). Body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) were the main predictors. Acute (past 8 days) and chronic (≥3 months) insomnia were assessed in 2014 via a self-report questionnaire. We fit multivariable logistic regression models providing odds ratios (OR) and 95% confidence intervals (CI). Results: Overweight (25.0 ≤ BMI < 30.0 kg/m2) and general obesity (BMI ≥ 30.0 kg/m2) appeared to have an inverse association with acute insomnia only among men (overweight: OR= 0.80, 95% CI: 0.70, 0.92; obesity: OR= 0.78, 95% CI: 0.63, 0.98). Obesity assessed by BMI and WHR appeared to be positively associated with chronic insomnia only among women (BMI: OR= 1.23, 95% CI: 1.04, 1.45; WHR: OR= 2.24, 95% CI: 1.07, 4.72). WC did not display any significant associations in either sex. Conclusions: These cross-sectional results revealed sex-specific associations of overweight/obesity with different types of insomnia, and merit confirmation longitudinally with objectively assessed sleep parameters. Nonetheless, the findings reinforce the critical importance of joint health behaviour promotion.

Major Change in Body Weight over 5 Years and Total Sleep Time: Investigation of Effect Modification by Sex and Obesity in a Large e-Cohort.

PURPOSE: We assessed the association of long-term weight change ≥5 kg with total sleep time (TST), investigating effect modification by sex and overweight/obesity. METHOD: In a cross-sectional context, we studied 41,610 adults from the general population-based NutriNet-Santé e-cohort. A sleep questionnaire was self-administered in 2014. It included sleep logs for the estimation of average TST at night, and items for the calculation of major weight change as experienced over the previous 5 years. We fit multivariate polytomous logistic regression models. RESULTS: Overall, women with major weight loss had an increased likelihood of short TST (≤6 h) when compared with women with stable weight (OR = 1.15, 95% CI: 1.05-1.25). Individuals with major weight gain had an increased likelihood of short TST compared with their counterparts with stable weight (men: OR = 1.20, 95% CI: 1.05-1.37; women: OR = 1.24, 95% CI: 1.15-1.33). Men with major weight gain were less likely to report long TST compared with men with stable weight (OR = 0.83, 95% CI: 0.70-0.97). Overweight or obesity did not moderate the associations. CONCLUSIONS: The study advances knowledge in the fields of public health and nutrition by providing some evidence of a sex-specific association of major weight change with both short and long TST. These associations merit future investigation in a longitudinal context with repeated, objective measures of both weight and sleep time, while applying more stringent interaction test criteria and accounting for changes in health behaviors.

The consensus sleep diary: quantitative criteria for primary insomnia diagnosis.

OBJECTIVE: The aim of the study was to put forward quantitative criteria for the Consensus Sleep Diary, to differentiate people with insomnia from normal sleepers. METHODS: In this retrospective study, we analyzed 295 sleep diaries of patients with primary insomnia (43% were male, ages ranging between 17 and 76 years) collected in two clinical centers for insomnia and 536 sleep diaries of normal sleepers (47% were male, ages ranging between 15 and 82 years). We considered the following sleep parameters: time in bed, sleep onset latency, total sleep time, wake after sleep onset, sleep efficiency, number of awakenings, terminal wakefulness, and subjective feeling of rest. Using the Youden index, we calculated the quantitative criteria that performed best for each sleep parameter. Finally, we created receiver operating characteristic curves to test the accuracy of each identified criterion. RESULTS: Individuals with insomnia significantly differed from controls on all sleep indices (p < .001). Differentiation between individuals with insomnia from controls was optimal for terminal wakefulness (>15 minutes, area under the curve [AUC] = 0.83), wake after sleep onset (cutoff >20 minutes, AUC = 0.81), total sleep time (<390 minutes, AUC = 0.80), and particularly sleep efficiency (<87.5%, AUC = 0.92, sensitivity = 0.80, specificity = 0.90). Time in bed was the least differentiating variable (<500 minutes, AUC = 0.57). CONCLUSIONS: The quantitative criteria of the sleep diary in this study agree with the few available data in the literature. This confirms that the sleep diary could be a useful screening tool for assessing patients with primary insomnia.

Insomnia and accidents: cross-sectional study (EQUINOX) on sleep-related home, work and car accidents in 5293 subjects with insomnia from 10 countries.

The link between sleepiness and the risk of motor vehicle accidents is well known, but little is understood regarding the risk of home, work and car accidents of subjects with insomnia. An international cross-sectional survey was conducted across 10 countries in a population of subjects with sleep disturbances. Primary care physicians administered a questionnaire that included assessment of sociodemographic characteristics, sleep disturbance and accidents (motor vehicle, work and home) related to sleep problems to each subject. Insomnia was defined using the International Classification of Sleep Disorders (ICSD-10) criteria. A total of 5293 subjects were included in the study, of whom 20.9% reported having had at least one home accident within the past 12 months, 10.1% at least one work accident, 9% reported having fallen asleep while driving at least once and 4.1% reported having had at least one car accident related to their sleepiness. All types of accident were reported more commonly by subjects living in urban compared to other residential areas. Car accidents were reported more commonly by employed subjects, whereas home injuries were reported more frequently by the unemployed. Car accidents were reported more frequently by males than by females, whereas home accidents were reported more commonly by females. Patients with insomnia have high rates of home accidents, car accidents and work accidents related to sleep disturbances independently of any adverse effects of hypnotic treatments. Reduced total sleep time may be one factor explaining the high risk of accidents in individuals who complain of insomnia.

[Occupational diseases and night-shift work]. / Pathologies professionnelles liées au travail posté ou de nuit.

Shift and night work concern every year more and more workers, specifically women. Recent recommendations on good practice for the medical surveillance of shift and night workers have been edited in France. They confirmed that this kind of organisation, unavoidable in some economical sectors is associated with a significant higher risk of sleep and wake disorders, cardiovascular disorders, overweight and obesity, breath cancer. Specific surveillance of shift and night workers is recommended in occupational health.

Sleep disturbances and incident risk of major depressive disorder in a population-based cohort.

Sleep disturbances are well-known symptoms of major depressive disorder (MDD). However, the prospective risk of MDD in the presence of sleep disturbances in a general population-based cohort is not well known. This study investigated associations between both polysomnography (PSG)-based or subjective sleep features and incident MDD. Participants representative of the general population who had never had MDD completed sleep questionnaires (n = 2000) and/or underwent PSG (n = 717). Over 8 years' follow-up, participants completed psychiatric interviews enabling the diagnosis of MDD. Survival Cox models were used to analyze associations between sleep features and MDD incidence. A higher Epworth Sleepiness Scale and presence of insomnia symptoms were significantly associated with a higher incidence of MDD (hazard ratio [HR] [95 % confidence interval (CI)]: 1.062 [1.022-1.103], p = 0.002 and 1.437 [1.064-1.940], p = 0.018, respectively). Higher density of rapid eye movements in rapid eye movement (REM) sleep was associated with a higher incidence of MDD in men (HR 1.270 [95 % CI 1.064-1.516], p = 0.008). In women, higher delta power spectral density was associated with a lower MDD incidence (HR 0.674 [95 % CI 0.463-0.981], p = 0.039). This study confirmed the associations between subjective and objective sleep features and the incidence of MDD in a large community dwelling cohort.

Effect of oxybutynin and reboxetine on obstructive sleep apnea: a randomized, placebo-controlled, double-blind, crossover trial.

STUDY OBJECTIVES: Although recent investigations combining noradrenergic and antimuscarinic drugs have shown promising short-term results to treat obstructive sleep apnea (OSA), the mid-term effect and optimal dosage remain uncertain. The present study aimed to evaluate the effect of 1 week of 5 mg oxybutynin and 6 mg reboxetine (oxy-reb) on OSA versus placebo. METHODS: We performed a randomized, placebo-controlled, double-blind, crossover trial comparing the effect of 1 week of oxy-reb versus 1 week of placebo on OSA severity. At-home polysomnography was performed at baseline and after each week of intervention. RESULTS: Fifteen participants (male 66.7%) aged 59 [44-62] years (median [interquartile range]) with a mean body mass index of 33.1 ± 6.6 kg/m2 were included. No significant difference in apnea-hypopnea index (AHI) was observed between conditions (estimated marginal means [95% confidence interval] at baseline: 39.7 [28.5-55.3]; oxy-reb: 34.5 [22.7-52.3]; placebo: 37.9 [27.1-52.9]; p = 0.652), but oxy-reb improved average oxygen desaturation (p = 0.016) and hypoxic burden (p = 0.011) and lowered sleep efficiency (p = 0.019) and rapid eye movement sleep (p = 0.002). Moreover, participants reported reduced sleep quality during the week of oxy-reb compared to the week of placebo (4.7 [3.5; 5.9] vs. 6.5 [5.5; 7.5] on a 0-10 visual analogic scale, respectively; p = 0.001). No significant differences in sleepiness, vigilance, and fatigue were observed. No serious adverse events occurred. CONCLUSIONS: Administration of oxybutynin 5 mg and reboxetine 6 mg did not improve OSA severity assessed by AHI, but did alter sleep architecture and sleep quality. Reduced average oxygen desaturation and hypoxic burden were also observed. CLINICAL TRIAL: ClinicalTrials.gov, https://clinicaltrials.gov, NCT04394143.

Periodic leg movements during sleep and cognitive functioning in the older general population.

OBJECTIVE: The current evidence of a relationship between periodic leg movements during sleep (PLMS) and cognitive functioning is limited and inconsistent. This cross-sectional study assessed associations between PLMS and cognitive functioning among community-dwelling older adults. METHODS: We included community-dwelling older adults who underwent a polysomnography and a cognitive assessment. The PLMS index (PLMI) and PLMS arousal index (PLMAI) were categorized into tertiles: PLMI <5/h (reference), 5-29.9/h, ≥30/h; and PLMAI <1/h (reference), 1-4.9/h, ≥5/h. The cognitive assessment consisted of ten scores covering the main cognitive domains: global cognition, processing speed, executive function, language, episodic verbal memory, and visuospatial function. Associations between PLMI, PLMAI, and cognitive scores were assessed using regression unadjusted and adjusted models. RESULTS: A total of 579 individuals without dementia were included (mean age: 71.5 ± 4.4 years; men 45.4%). The number of participants in the high-PLMI categories, 5-29.9/h and ≥30/h, was 185 (32.0%) and 171 (29.5%), respectively. Participants in the high-PLMI categories showed no significant difference compared to the reference group regarding their cognitive performance according to the unadjusted and adjusted models. Similarly, we found no association between PLMAI severity and cognitive functioning. CONCLUSIONS: This study shows no cross-sectional association between PLMS severity and cognitive functioning among community-dwelling older adults. However, given the paucity of data in this field, further studies are needed to clarify the relationship between PLMS and cognitive functioning.

Objective polysomnography-based sleep features and major depressive disorder subtypes in the general population.

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.

The Relationship Between Postoperative Opioid Analgesia and Sleep Apnea Severity in Patients Undergoing Hip Arthroplasty: A Randomized, Controlled, Triple-Blinded Trial.

PURPOSE: Residual postoperative pain after hip arthroplasty is usually treated with oral opioids. While classic opioids are associated with respiratory depression and worsening of sleep apnea, tramadol has been reported to preserve respiratory function. However, this has not been investigated in a prospective trial using respiratory polygraphy. This randomized controlled triple-blinded trial tested the hypothesis that postoperative treatment with oral opioids such as oxycodone would increase sleep apnea severity, measured with a respiratory polygraphy, compared with oral tramadol. PATIENTS AND METHODS: Sixty patients undergoing hip arthroplasty under spinal anesthesia with 15 mg isobaric bupivacaine 0.5% were randomized to receive postoperative pain treatment with either oral oxycodone (controlled-release 10 mg every 12 hours and immediate-release 5 mg every 4 hours as needed) or oral tramadol (controlled-release 100 mg every 8 hours and immediate-release 50 mg every 4 hours as needed). Respiratory polygraphy was performed on the first postoperative night. The primary outcome was the apnea-hypopnea index in the supine position. Secondary outcomes included the oxygen desaturation index, postoperative pain scores and intravenous morphine consumption. RESULTS: Mean supine apnea-hypopnea index on postoperative night 1 was 11.3 events.h-1 (95% confidence interval, 4.8-17.7) in the oxycodone group and 10.7 (4.6-16.8) events.h-1 in the tramadol group (p=0.89). There were no significant differences between the oxycodone and tramadol groups with respect to any secondary sleep-related or pain-related outcomes. CONCLUSION: Oral oxycodone did not increase sleep apnea severity measured using respiratory polygraphy compared with oral tramadol on the first postoperative night after hip arthroplasty. TRIAL REGISTRATION NUMBER: Clinicaltrials.gov - NCT03454217 (date of registration: 05/03/2018).

Impact of night and shift work on metabolic syndrome and its components: a cross-sectional study in an active middle-to-older-aged population-based sample.

OBJECTIVES: To examine the effects of work schedules on metabolic syndrome and its components in active middle-to-older-aged workers. METHODS: A cross-sectional analysis including middle-to-older-aged active workers from the population-based CoLaus|PsyCoLaus study (Lausanne, Switzerland) was performed. Work schedule was self-reported and defined as follows: permanent day, day shift, night shift and permanent night work. Associations between work schedule and the risk of metabolic syndrome and its components were analysed using multivariable-adjusted logistic regressions. RESULTS: A total of 2301 active workers (median age (IQR): 55.4 (50.8 to 60.4), 50.1% women) were included. Of these, 1905 were permanent day workers, 220 were day-shift workers, 134 were night-shift workers and 42 were permanent night-shift workers. There were significant interactions between sex and work schedule for metabolic syndrome, high triglycerides and visceral obesity. Men but not women permanent night workers had a higher prevalence of metabolic syndrome than permanent day workers in multivariable-adjusted analyses (OR 4.45 (95% CI 1.36 to 14.56)). Analysis of metabolic syndrome subcomponents showed that the association between work schedule and metabolic syndrome in men was mainly driven by visceral obesity (OR 3.35 (95% CI 1.04 to 10.76)). Conversely, women but not men working in night shift were at increased risk of having high triglycerides compared with permanent day workers (OR 2.92 (95% CI 1.03 to 8.27)). CONCLUSIONS: The risk of metabolic syndrome is higher in men working in permanent night shift compared with permanent day work, and this association could be mediated by visceral obesity.

Association Between Sleep Microstructure and Incident Hypertension in a Population-Based Sample: The HypnoLaus Study.

Background Poor sleep quality is associated with increased incident hypertension. However, few studies have investigated the impact of objective sleep structure parameters on hypertension. This study investigated the association between sleep macrostructural and microstructural parameters and incident hypertension in a middle- to older-aged sample. Methods and Results Participants from the HypnoLaus population-based cohort without hypertension at baseline were included. Participants had at-home polysomnography at baseline, allowing assessment of sleep macrostructure (nonrapid eye movement sleep stages 1, 2, and 3; rapid eye movement sleep stages; and total sleep time) and microstructure including power spectral density of electroencephalogram in nonrapid eye movement sleep and spindles characteristics (density, duration, frequency, amplitude) in nonrapid eye movement sleep stage 2. Associations between sleep macrostructure and microstructure parameters at baseline and incident clinical hypertension over a mean follow-up of 5.2 years were assessed with multiple-adjusted logistic regression. A total of 1172 participants (42% men; age 55±10 years) were included. Of these, 198 (17%) developed hypertension. After adjustment for confounders, no sleep macrostructure features were associated with incident hypertension. However, low absolute delta and sigma power were significantly associated with incident hypertension where participants in the lowest quartile of delta and sigma had a 1.69-fold (95% CI, 1.00-2.89) and 1.72-fold (95% CI, 1.05-2.82) increased risk of incident hypertension, respectively, versus those in the highest quartile. Lower spindle density (odds ratio, 0.87; 95% CI, 0.76-0.99) and amplitude (odds ratio, 0.98; 95% CI, 0.95-1.00) were also associated with higher incident hypertension. Conclusions Sleep microstructure is associated with incident hypertension. Slow-wave activity and sleep spindles, 2 hallmarks of objective sleep continuity and quality, were inversely and consistently associated with incident hypertension. This supports the protective role of sleep continuity in the development of hypertension.

Sleepiness, near-misses and driving accidents among a representative population of French drivers.

Study objectives were to determine the prevalence of sleepy driving accidents and to explore the factors associated with near-miss driving accidents and actual driving accidents in France. An epidemiological survey based on telephone interviews was conducted on a representative sample of French drivers. The questionnaire included sociodemographics, driving and sleep disorder items, and the Epworth sleepiness scale. Of 4774 drivers (response rate: 86%), 28% experienced at least one episode of severe sleepiness at the wheel (i.e. requiring to stop driving) in the previous year; 11% of drivers reported at least one near-miss accident in the previous year (46% sleep-related); 5.8% of drivers reported at least one accident, 5.2% of these being sleep related (an estimate of 90,000 sleep-related accidents per year in France). Sleepy driving accidents occurred more often in the city (53.8%), during short trips (84.6%) and during the day (84.6%). Using logistic regression, the best predictive factor for near-misses was the occurrence of at least one episode of severe sleepiness at the wheel in the past year [odds ratio (OR) 6.50, 95% confidence interval (CI), 5.20-8.12, P < 0.001]. The best predictive factors for accidents were being young (18-30 years; OR 2.13, 95% CI, 1.51-3.00, P < 0.001) and experiencing at least one episode of severe sleepiness at the wheel (OR 2.03, 95% CI, 1.57-2.64, P < 0.001). Sleepiness at the wheel is a risk factor as important as age for traffic accidents. Near-misses are highly correlated to sleepiness at the wheel and should be considered as strong warning signals for future accidents.

Maintenance of Wakefulness Test, obstructive sleep apnea syndrome, and driving risk.

OBJECTIVE: Sleepiness at the wheel is a major risk factor for traffic accidents. Because of the potential medical and legal implications, in this study, we evaluated the correlation between subjective and objective measures of sleepiness and driving performances in patients suffering from excessive daytime sleepiness. METHODS: Thirty-eight untreated sleep apnea patients (mean age +/- standard deviation, 51 +/- 9 years; mean apnea-hypopnea index +/- standard deviation, 41 +/- 25), and 14 healthy control subjects (mean age +/- standard deviation, 46 +/- 9 years) were included in the study. Nocturnal polysomnography, mean sleep latency as measured by four 40-minute Maintenance of Wakefulness Test (MWT) trials, Epworth Sleepiness Scale, Karolinska Sleepiness Scale, and the number of inappropriate line crossings during a 90-minute real-life driving session were analyzed. RESULTS: The number of inappropriate line crossings correlated with MWT scores (Spearman's Rho: r = -0.339; p < 0.05), Karolinska Sleepiness Scale scores measured at halfway in total driving distance (Rho: r = 0.367; p < 0.01), and Epworth Sleepiness Scale (Rho: r = 0.389; p < 0.01). We found a significant difference in the number of inappropriate line crossings among the four groups defined by MWT scores (very sleepy [0-19 minutes], sleepy [20-33 minutes], alert [34-40 minutes], and controls) (Kruskal-Wallis test: H = 11.319; p < 0.01). Very sleepy and sleepy patients had more inappropriate line crossings than the control drivers (p < 0.05). INTERPRETATION: In addition to subjective sleepiness scales, the MWT can be used to assess driving ability in untreated sleep apnea patients.

The association between physical and mental chronic conditions and napping.

The objectives of this study were to assess the associations among various physical and mental chronic conditions and napping. A cross-sectional epidemiological survey was proposed within the NutriNet-Santé population-based e-cohort launched in France in 2009. Participants were 43,060 French volunteers aged 18 y and over with Internet access. A self-report questionnaire assessing sleep characteristics was administered in 2014. The main outcome (dependent) variable was weekday or weekend napping (yes/no). The main exposure (independent) variables were overweight/obesity, hypertension, diabetes, anxiety and depressive disorders, incident major cardiovascular diseases (myocardial infarction, stroke, unstable angina), and incident cancer (breast and prostate). The associations of interest were investigated with multivariable logistic regression analysis. No significant associations were found between major cardiovascular diseases or breast or prostate cancer and napping. Instead, we found that napping was more common among males (46.1%) than among females 36.9% (p < 0.0001). Individuals who were overweight or obese or had hypertension, diabetes, depression or anxiety disorders had an increased likelihood of napping compared with their healthy peers. The adjusted ORs ranged from 1.14 to 1.28″. In conclusion, most chronic conditions were independently associated with napping. Future longitudinal analyses are needed to elucidate causality.