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Introduction: This paper describes the development of “Swedish Guidelines for OSA treatment” and the underlying managed care process. The Apnea Hypopnea Index (AHI) is traditionally used as a single parameter for obstructive sleep apnea (OSA) severity classification, although poorly associated with symptomatology and outcome. We instead implement a novel matrix for shared treatment decisions based on available evidence. Methods: A national expert group including medical and dental specialists, nurses, and patient representatives developed the knowledge-driven management model. A Delphi round was performed amongst experts from all Swedish regions (N = 24). Evidence reflecting treatment effects was extracted from systematic reviews, meta-analyses, and randomized clinical trials. Results: The treatment decision in the process includes a matrix with five categories from a “very weak”” to “very strong” indication to treat, and it includes factors with potential influence on outcome, including (A) OSA-related symptoms, (B) cardiometabolic comorbidities, (C) frequency of respiratory events, and (D) age. OSA-related symptoms indicate a strong incitement to treat, whereas the absence of symptoms, age above 65 years, and no or well-controlled comorbidities indicate a weak treatment indication, irrespective of AHI. Conclusions: The novel treatment matrix is based on the effects of treatments rather than the actual frequency of respiratory events during sleep. A nationwide implementation of this matrix is ongoing, and the outcome is monitored in a prospective evaluation by means of the Swedish Sleep Apnea Registry (SESAR).

Accelerometers placed on the thigh provide accurate measures of daily physical activity types, postures and sedentary behaviours, over 24 h and across consecutive days. However, the ability to estimate sleep duration or quality from thigh-worn accelerometers is uncertain and has not been evaluated in comparison with the ‘gold-standard’ measurement of sleep polysomnography. This study aimed to develop an algorithm for sleep estimation using the raw data from a thigh-worn accelerometer and to evaluate it in comparison with polysomnography. The algorithm was developed and optimised on a dataset consisting of 23 single-night polysomnography recordings, collected in a laboratory, from 15 asymptomatic adults. This optimised algorithm was then applied to a separate evaluation dataset, in which, 71 adult males (mean [SD] age 57 [11] years, height 181 [6] cm, weight 82 [13] kg) wore ambulatory polysomnography equipment and a thigh-worn accelerometer, simultaneously, whilst sleeping at home. Compared with polysomnography, the algorithm had a sensitivity of 0.84 and a specificity of 0.55 when estimating sleep periods. Sleep intervals were underestimated by 21 min (130 min, Limits of Agreement Range [LoAR]). Total sleep time was underestimated by 32 min (233 min LoAR). Our results evaluate the performance of a new algorithm for estimating sleep and outline the limitations. Based on these results, we conclude that a single device can provide estimates of the sleep interval and total sleep time with sufficient accuracy for the measurement of daily physical activity, sedentary behaviour, and sleep, on a group level in free-living settings.

STUDY OBJECTIVES: Whether short or insufficient sleep are risk factors for new-onset nocturnal gastroesophageal reflux (nGER). METHODS: In this 10-year longitudinal study, adult general-population women in Uppsala, Sweden, answered questionnaires on sleep, nGER, and other conditions on 2 occasions. Participants at baseline totaled 6,790, while participants at follow-up totaled 4,925. “Short sleep” was defined as sleeping < 6 hours/night and “insufficient sleep” was defined as reporting an average actual sleep duration below 80% of the self-estimated need for sleep duration but without “short sleep.” nGER was defined as reporting heartburn or acid reflux after going to bed sometimes, often, or very often. The confounding factors—age, body mass index, physical activity, caffeine intake, smoking habits, alcohol dependence, depression, anxiety, and snoring—were defined from the questionnaire. RESULTS: At baseline, 839 participants reported short sleep and 1,079 participants were defined as having insufficient sleep. Both participants with insufficient sleep and short sleep had nGER more often than those with sufficient sleep (26% vs 17% vs 10%, respectively). At follow-up, a new onset of nGER was twice as common among those with insufficient or short sleep at baseline and follow-up, compared with those with sufficient sleep at baseline and follow-up, even after adjusting for confounding factors (odds ratio 2.0 [1.5–2.8], P < .001). CONCLUSIONS: Insufficient sleep and short sleep are associated with nGER. Persistent insufficient and/or short sleep independently increases the risk of developing nGER over a 10-year follow-up. Women seeking treatment for nGER should be questioned about their sleep habits to identify insufficient sleep as a possible causative factor. CITATION: Emilsson OI, Al Yasiry H, Theorell-Haglöw J, Ljunggren M, Lindberg E. Insufficient sleep and new onset of nocturnal gastroesophageal reflux among women: a longitudinal cohort study. J Clin Sleep Med. 2022;18(7):1731–1737.

Obstructive sleep apnea (OSA) is a common sleep-related breathing disorder. In animal models, OSA has been shown to alter the gut microbiota; however, little is known about such effects in humans. Here, we used respiratory polygraphy data from 3,570 individuals aged 50–64 from the Swedish CardioPulmonary bioImage Study (SCAPIS) and deep shotgun metagenomics to identify OSA-associated gut microbiota features. We found that OSA-related hypoxia parameters were associated with 128 bacterial species, including positive associations with Blautia obeum and Collinsela aerofacines. The latter was also associated with increased systolic blood pressure. Further, the cumulative time in hypoxia was associated with nine gut microbiota metabolic pathways, including propionate production from lactate, a biomarker of hypoxia. In conclusion, in this first large-scale study on gut microbiota alterations in OSA, we found that OSA-related hypoxia is associated with specific microbiota features. Our findings can direct future research on microbiota-mediated health effects of OSA.

The relationship between sleep duration and sleepiness has seen much research, but no data are available on the association between polysomnographically (PSG) determined total sleep time (TST) (or other PSG variables) and subjective sleepiness during the subsequent day in individuals in their habitual life situation. The purpose of the present study was to study the association between TST and sleep efficiency (SE) (and other PSG variables) and next-day sleepiness at 7 times of the day. A large population-based group of women (N = 400) participated. Daytime sleepiness was measured with the Karolinska Sleepiness Scale (KSS). The association was studied through analysis of variance (ANOVA), as well as regression analyses. For SE there was a significant difference in sleepiness across groups with >90%, 80%–89.99%, and 0.45) was seen for both analyses, with maximum sleepiness at bedtime (≈ 7.5 KSS units). A multiple regression analysis, including all PSG variables (adjusted for age and BMI), showed that SE was a significant predictor (β = 0.16, p < .05) of mean sleepiness, even after depression, anxiety, and subjective sleep duration were entered, but this was eliminated by subjective sleep quality. It was concluded that high SE is modestly associated with lower next-day sleepiness in women in a real-life context, but that TST is not.

Rapid eye movement (REM) obstructive sleep apnea might be particularly harmful to the cardiovascular system. We aimed to investigate the association between sleep apnea during REM sleep and signs of atherosclerotic disease in the form of carotid intima thickness in a community-based sample of men and women and possible sex differences in this association. The association between sleep apnea during REM sleep and intima thickness was analysed cross-sectionally in women from the community-based “Sleep and Health in Women” (SHE) study (n = 253) and age- and body mass index (BMI)-matched men from the “Men in Uppsala; a Study of sleep, Apnea and Cardiometabolic Health” (MUSTACHE) study (n = 338). Confounders adjusted for were age, BMI, gender, alcohol, and smoking. All participants underwent a full-night polysomnography, high-resolution ultrasonography of the common carotid artery, anthropometric measurements, blood pressure measurements, and answered questionnaires. There was an association between sleep apnea during REM sleep and thicker carotid intima that remained after adjustment for confounding (adjusted β = 0.008, p = 0.032). The intima was increased by 9.9% in the group with severe sleep apnea during REM sleep, and this association between severe sleep apnea during REM sleep and increased intima thickness remained after adjustment for confounders (adjusted β = 0.043, p = 0.021). More women than men had severe sleep apnea during REM sleep; moreover, in sex-stratified analyses, the association between sleep apnea during REM sleep and intima thickness was found in women but not in men. We conclude that severe REM sleep apnea is independently associated with signs of atherosclerosis. When stratified by sex, the association is seen in women but not in men.

STUDY OBJECTIVES: The aim of this study was to determine whether severity measures of obstructive sleep apnea (OSA) are associated with arterial stiffness and central blood pressure (two important cardiovascular risk factors) in a large group of patients with OSA. METHODS: Baseline data from six studies on OSA in which arterial stiffness and central aortic blood pressure measures were determined using applanation tonometry were pooled. Associations between measures of arterial stiffness (heart rate corrected augmentation index [AI75]), central aortic blood pressure (central systolic pressure [CSP] and heart rate corrected central augmentation pressure [CAP75]) and measures of OSA severity were explored using stepwise regression modelling. RESULTS: Data from 362 participants (M:F ratio 13:1) with mean (standard deviation) age 49.2 (11.0) years, body mass index 31.9 (5.3) kg/m(2), apnea-hypopnea index (AHI) 35.7 (20.7) events/h were included in the analyses. The AHI, oxygen desaturation index (ODI3%), and sleep time with SpO(2) < 90% (T90) were all associated with arterial stiffness (AI75), (AHI: adj. β = .069; P = .01; ODI3%: adj. β = .072; P = .01; T90: adj. β = .18; P < .0001) and CAP75 (AHI: adj. β = .030; P = .01; ODI3%: adj. β = .027; P = .02; T90: adj. β = .080; P < .0001). AHI was also associated with CSP (AHI: adj. β = .11; P = .002). CONCLUSION: OSA severity was significantly associated with augmentation index and CAP75 although the relationships were not strong. CITATION: Theorell-Haglöw J, Hoyos CM, Phillips CL, Yee BJ, Melehan KL, Liu PY, Cistulli PA, Grunstein RR. Associations between obstructive sleep apnea and measures of arterial stiffness. J Clin Sleep Med. 2019;15(2):201–206.

Combined insomnia and obstructive sleep apnea has been the focus of considerable research with respect to its health effects. A related issue is whether sleep disturbances in combination with snoring might exert effects on objective sleep variables in the non-clinical general population. The purpose of the present study was to investigate the polysomnographical characteristics of individuals who had sought medical help for both disturbed sleep and for snoring. No previous work of this type has been carried out.For this study we used a representative set of data of 384 women with one night of in-home PSG. We identified those individuals who had sought medical help for sleep problems (SL), individuals that had sought help for snoring (SN), as well as those that had sought help for either both (Combined), or for neither (Control).Our results yielded an N of 46, 16, 21, and 301 individuals, respectively. A one-factor analysis of variance showed significant main effects on N1% (F = 10.2, p 0.001), N3% (F = 2.7, p 0.05), AHI/h (F = 5.5, p 0.001), and a delta power measure (F = 3.8, p 0.05). The combined group showed significantly higher levels than the other groups for N1% (29% vs 21%), AHI/h (19/h vs 10/h) and lower levels for N3%, and a measure of delta power. Reported sleep quality measures did not show the same pattern, since the highest/lowest value were found for either the group presenting snoring alone or sleep problems alone.We concluded that individuals who had sought help for both insomnia and snoring showed impaired sleep in terms of PSG and that this was not reflected in ratings of sleep or health. This suggests that simultaneous sleep disturbances and snoring may potentiate each other to cause impaired sleep, yet the mechanism still needs to be elucidated.

Objectives Adherence to continuous positive airway pressure (CPAP) in patients with obstructive sleep apnea (OSA) is crucial. Our aim was to identify protective and risk factors against the discontinuation of CPAP treatment in patients with OSA and to estimate the mortality risk in those who were non-adherent to CPAP therapy. Methods This was a registry-based cohort study from 37 centers across Sweden with OSA patients on CPAP in the Swedevox Swedish national registry between July 2010 and March 2017. Results In 16,425 patients (70.8% men) with complete follow-up data after 1.2 ± 0.8 years the adjusted relative risk ratio (aRRR) for the discontinuation of CPAP was 0.57 (95% confidence interval (CI) 0.50–0.65) for use of humidifier, 0.87 (95% CI 0.82–0.92) for increasing age per 10 years, 0.80 (95% CI 0.77–0.83) for increasing apnea hypopnea index (AHI) per 5 units/hour, and 0.96 (95% CI 0.95–0.97) per increased unit on the Epworth Sleepiness Scale (ESS). Increasing BMI was associated with increased adherence up to BMI 35. Women and patients with hypertension ran an increased risk of discontinuing CPAP treatment, aRRR 1.28 (95% CI 1.12–1.46) and 1.24 (95% CI 1.12–1.42) respectively. The adjusted hazard ratio (HR) for mortality was 1.74 (95% CI 1.32–2.28) among those who did not adhere to CPAP (median follow-up period 2.4 years after the one year adherence evaluation). Conclusion Use of humidifier is associated with greater adherence to CPAP treatment. Other factors predicting adherence are increasing age, more severe OSA and overweight up to BMI 35, whereas female gender and coexisting hypertension are risk factors for discontinuation of CPAP. Failure to adhere to CPAP is associated with increased mortality.

According to the “3P model” of insomnia, the variable that mediates the transition from acute insomnia (AI) to chronic insomnia is “sleep extension” (the behavioural tendency to expand sleep opportunity to compensate for sleep loss). In the present analysis, we sought to evaluate how time in bed (TIB) varies relative to the new onset of AI and chronic insomnia. A total of 1,248 subjects were recruited as good sleepers (GS). Subjects were monitored over 1 year with sleep diaries. State transitions were defined, a priori, for AI, recovered from AI (AI-REC), and for chronic insomnia (AI-CI). Two additional groupings were added based on profiles that were unanticipated: subjects that exhibited persistent poor sleep following AI (AI-PPS [those that neither recovered or developed chronic insomnia]) and subjects that recovered from chronic insomnia (CI-REC). All the groups (GS, AI-REC, AI-CI, AI-PPS and CI-REC) were evaluated for TIB differences with longitudinal mixed effects models. Post hoc analyses for the percentage of the groups that were typed as TIB “restrictors, maintainers, and expanders” were conducted using longitudinal mixed effects models and contingency analyses. Significant differences for pre-post AI TIB were not detected for the insomnia groups. Trends were apparent for the AI-CI group, which suggested that minor increases in TIB occurred weeks before the declared onset of AI. Additionally, it was found that a significantly larger percentage of AI-CI subjects engaged in sleep extension (as compared to GS). The present data suggest that transition from AI to chronic insomnia does not appear to be initiated by sleep extension and the transition may occur before the elapse of 3 months of ≥3 nights of sleep continuity disturbance. Given these findings, it may be that the mismatch between sleep ability and sleep opportunity is perpetuated over time given the failure to “naturally” engage in sleep restriction (as opposed to sleep extension).

ObjectiveHabitual snoring is associated with fatigue, headaches and low work performance. This cross-sectional study aimed to investigate if snoring is affected by environmental factors such as home dampness and exposure to air pollution.SettingGeneral population sample from four Swedish cities.Participants25 848 participants from the Swedish part of the epidemiological Global Asthma and Allergy and European network of excellence study carried out in 2008. The participants completed a postal questionnaire on snoring and, indoor and outdoor environmental exposure as well as potential confounders including smoking, weight, height and educational level.ResultsOf the participants, 4211 (16.3%) were habitual snorers. Habitual snorers reported water damage (8.3% vs 7.0% pConclusionSnoring is more prevalent in subjects reporting home dampness and air pollution. These association should be confirmed in further research using objective measurements and a longitudinal approach.

Study Objectives Individuals with evening chronotype have a higher risk of cardiovascular and metabolic disorders, although the underlying mechanisms are not well understood. In a population-based cohort, we aimed to investigate the association between chronotype and 242 circulating proteins from three panels of established or candidate biomarkers of cardiometabolic processes. Methods In 2,471 participants (49.7% men, mean age 61.2 ± 8.4 SD years) from the EpiHealth cohort, circulating proteins were analyzed with a multiplex proximity extension technique. Participants self-reported their chronotype on a five-level scale from extreme morning to extreme evening chronotype. With the intermediate chronotype set as the reference, each protein was added as the dependent variable in a series of linear regression models adjusted for confounders. Next, the chronotype coefficients were jointly tested and the resulting p-values adjusted for multiple testing using a false discovery rate (5%). For the associations identified, we then analyzed the marginal effect of each chronotype category. Results We identified 17 proteins associated with chronotype. Evening chronotype was positively associated with proteins previously linked to insulin resistance and cardiovascular risk, namely retinoic acid receptor protein 2, fatty acid-binding protein adipocyte, tissue-type plasminogen activator, and plasminogen activator inhibitor 1 (PAI-1). Additionally, PAI-1 was inversely associated with the extreme morning chronotype. Conclusions In this population-based study, proteins previously related to cardiometabolic risk were elevated in the evening chronotypes. These results may guide future research in the relation between chronotype and cardiometabolic disorders.

Systemic inflammation is thought to mediate the link between sleep and cardiovascular outcomes, but previous studies on sleep habits and inflammation markers have found inconsistent results. This study investigated the relationship between sleep characteristics and C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor α (TNFα). A representative sample of 319 Swedish women was randomly selected from the general population for in-home polysomnography, sleep questionnaire and blood samples. As variables were highly correlated, principal component analysis was used to reduce the number of original variables. Linear regression with log-transformation of the outcomes (lnCRP, lnIL-6 and lnTNFα) and quantile regression were fitted to estimate cross-sectional relationships. Multivariable linear regression models suggested a significant association of insomnia symptoms (self-reported) with higher lnCRP levels (β=0.11; 95% confidence interval [CI]=0.02; 0.21), but not with lnIL-6 and lnTNFα. From quantile regression analysis we found that a high non-restorative index (subjective) and insomnia symptoms (self-reported) were associated with higher values of CRP, especially in the highest quantiles of the CRP distribution (90th percentile: β=0.71; 95% CI=0.17; 1.24. β=1.23; 95% CI=0.44; 2.02, respectively). Additionally, higher amounts of rapid eye movement (REM) sleep were associated with lower CRP values (90th percentile: β=−0.80; 95% CI=−0.14; −1.46). In conclusion, sleep disturbances (self-reported), specifically difficulties maintaining sleep and early morning awakenings, but not sleep duration (neither subjective nor objective), were associated with higher CRP levels. No association was found with IL-6 or TNFα. Elevated REM sleep was associated with lower CRP levels. The results suggest that inflammation might be an intermediate mechanism linking sleep and health in women.

The worldwide COVID-19 pandemic has affected the operation of health care systems. The direct impact of obstructive sleep apnea (OSA) on COVID-19 infection outcome remains to be elucidated. However, the coincidence of common risk factors for OSA and severe COVID-19 suggests that patients with OSA receiving positive airway pressure therapy may have an advantage relative to those untreated when confronted with a COVID-19 infection. The ongoing COVID-19 pandemic has led to a substantial reduction of sleep medicine services, and the long-term consequences may be considerable. New strategies for the management of sleep disorders are needed to overcome the current underdiagnosis and delay of treatment.

Study objectives Obesity is often associated with lower lung function; however, the interaction of lung function with central obesity and physical inactivity is less clear. As such, we investigated the effect on lung function of body size (body mass index (BMI)), central obesity (waist circumference (WC)) and self-reported physical activity. Methods Lung function, height, weight and WC were measured in 22 743 participants (12 791 women), aged 45–75 years, from the EpiHealth cohort study. Physical activity, gender and educational level were assessed using a questionnaire. Results Obesity, central obesity and physical inactivity were all associated with lower forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC). However, in participants without central obesity there was an increase in both FEV1 and FVC by BMI (% predicted FVC increasing from median 98%, interquartile range (IQR) 89–110% in underweight participants (BMI, BMI and central obesity are related to lung function in the middle-aged and elderly. BMI association with lung function is dependent on the presence of central obesity, while the association of physical activity and lung function is independent of obesity. https://bit.ly/3eQl86C

PurposeChronic hypoxic and hypercapnic respiratory failure and obstructive sleep apnoea (OSA) are chronic diseases associated with decreased quality of life and increased mortality. The rationale behind the set up the retrospective nationwide DISCOVERY cohort was to study several questions including disease course and risk factors for incident disease, impaired quality of life, hospitalisation risk and mortality in patients with chronic respiratory failure with long-term oxygen therapy (LTOT), long-term mechanical ventilation (LTMV) and obstructive sleep apnoea (OSA) on treatment with continuous positive airway pressure (CPAP).Participants and settingsData from the national quality registry for respiratory insufficiency and sleep apnoea (Swedevox) and a population-based control group from Statistics Sweden were merged with governmental registries, the Swedish Cancer Registry, the Swedish Cause of Death Registry, the Swedish Drug registry, the Swedish National Patient Registry and the Swedish Dental Health Registry and with national quality registries for diabetes, rheumatic diseases (Swedish Rheumatology Quality Registry), stroke (RiksStroke), heart failure (RiksSvikt), acute heart infarction care (SwedeHeart) and intensive care (SIR) and with socioeconomic data from Statistics Sweden (SCB).Findings to dateThe cohort comprises 25 804 unique patients with LTOT since 1987 (54.1% females, age 73.3±9.8 years, body mass index (BMI) 26.6±6.5 kg/m2), 8111 with LTMV since 1996 (48.6% women, age 60.6±16.9 years, BMI 32.9±10.8 kg/m2), 65 809 with OSA on CPAP since 2010 (29.5% women, age 57.2±12.5 years, BMI 31.9±6.2 kg/m2) and 145 224 persons in a population-based control group from same time span up to March 2018 (51.7% women, age 49.9±20.4 year, BMI 24.9±4.0 years).Future plansIn patients with chronic respiratory failure and sleep apnoea important questions regarding comorbidity burden, hospitalisation rate, mortality and treatment outcomes are still unexplored to a large extent. The DISCOVERY cohort will provide unique opportunities by its size and comprehensiveness to fill this clinically relevant gap of knowledge.

Sinonasal complaints contribute to low adherence to continuous positive airway pressure (CPAP) treatment. We aimed to investigate sinonasal health in obstructive sleep apnoea (OSA) patients, using the sinonasal outcome test-22 (SNOT-22), and to analyse whether SNOT-22 is affected by CPAP adherence. We also aimed to investigate whether peak nasal inspiratory flow (PNIF) was able to predict adherence to CPAP.The study population comprised 197 OSA patients (60 females) initiating CPAP treatment. The SNOT-22, PNIF and the Epworth Sleepiness Scale were assessed at baseline and follow-up. One-night polygraphy, the Hospital Anxiety and Depression Scale, peak expiratory flow and health-related issues were assessed at baseline. At follow-up, the patients were categorised into adherent (more than 4 hours/night) and non-adherent (less than 4 hours/night) to CPAP treatment.The average time for following up CPAP treatment was (mean plus or minus SD) 24.0 plus or minus 23.9 days and it did not differ significantly between the groups. The SNOT-22 score was elevated among all OSA patients, 36.1 plus or minus 19.4. There was a larger improvement in the SNOT-22 score at follow-up among adherent CPAP users compared with non-adherent users (-10.4 plus or minus 13.9 vs. -3.2 plus or minus 15.4). A PNIF value of less than 100 litres/min increased the risk of non-adherence to CPAP with an adjusted odds ratio (OR) of 2.40 ((95% CI 1.16-5.00)).The SNOT-22 was elevated in patients with OSA, indicating a considerable sinonasal disease burden. The SNOT-22 improved with good CPAP adherence. A low PNIF value was able to predict poor CPAP adherence. Both the SNOT-22 and PNIF can be valuable tools in the evaluation of OSA patients and in the management of CPAP treatment.

STUDY OBJECTIVES: To investigate relationships between sleep duration and adherence to healthy diets, but also associations with meal patterns, in a large population-based cohort. METHODS: Participants (n = 23,829, males and females, aged 45 to 75 years) from the Swedish EpiHealth cohort study were included in a cross-sectional analysis. The participants filled out an extensive Internet-based questionnaire, and also visited a test center for anthropometric measurements and blood sampling. Sleep duration was classified as short (< 6 h/night; n = 1,862), normal (6 to less fewer than 9 h/night; n = 19,907) and long sleep (≥ 9 h/night; n = 858). In addition, a combination variable of sleep duration (short/normal/long) and sleep quality (good/poor) was constructed, giving six categories. Adherence to a healthy diet was assessed using the modified Mediterranean diet (mMED) score and the Healthy Nordic Food Index (HNFI) score based on food groups from a food frequency questionnaire. A regular meal pattern was considered if the participant had breakfast, lunch and dinner on a daily basis. RESULTS: Compared with normal sleepers, short sleepers displayed lower adherence to a healthy diet when using both the mMED score (adjusted odds ratio = 0.70; 95% confidence interval 0.56-0.88) and the HNFI score (0.70; 0.56–0.88). When combining sleep duration and sleep quality, short sleepers with poor sleep quality showed an independent relationship with low adherence to a healthy diet (0.67; 0.52–0.86) compared with normal sleepers with good sleep quality. In addition, both short sleepers (0.71; 0.62–0.82) and long sleepers (0.75; 0.62–0.91) showed low adherence to regular meal patterns, compared with normal sleepers. Furthermore, short sleepers with poor sleep quality had reduced odds of having a regular meal pattern (0.67; 0.57–0.79) as compared with normal sleepers with good sleep quality. CONCLUSIONS: Short sleep duration combined with poor sleep quality is associated with low adherence to a healthy diet and regular meal patterns. CITATION: Theorell-Haglöw J, Lemming EW, Michaëlsson K, Elmeståhl S, Lind L, Lindberg E. Sleep duration is associated with healthy diet scores and meal patterns: results from the population-based EpiHealth study. J Clin Sleep Med. 2020;16(1):9–18.

Purpose Obstructive sleep apnea (OSA) is associated with obesity and risk for type 2 diabetes. In this community-based study, we thoroughly investigated fatty acid metabolism, incretin response, glucose tolerance, insulin secretion and insulin sensitivity, and autonomic nerve activity in men with or without OSA. Methods Fifteen men without diabetes but with signs of severe OSA, defined as apnea–hypopnea index (AHI) >30, and 15 age- and BMI-matched men without OSA (AHI Results Men with OSA had higher body fat % than BMI-matched men without OSA (p = 0.046) and it was associated with markers of insulin resistance. The area under the curve for nonesterified fatty acids (NEFA) during OGTT was higher in men with OSA (p = 0.021) and fasting NEFA levels were numerically higher (p = 0.097). The plasma glucose at fasting and during OGTT was higher in men with OSA (p p = 0.068) and Gutt index (p Conclusions Our study suggests that fatty acid handling, glucose tolerance, and insulin sensitivity are impaired in men with severe OSA. This might partly be explained by the increased body fat percentage.

Proteomic-based technologies offer new opportunities to identify proteins that might reflect the cardiometabolic stress caused by different aspects of sleep-disordered breathing. We aimed to investigate whether severe obstructive sleep apnea and severe obstructive sleep apnea during rapid eye movement sleep are associated with changed levels of inflammatory and cardiac disease-related proteins in a population-based cohort of women. In the community-based "Sleep and Health in Women" (SHE) cohort study, 400 women underwent polysomnography, anthropometric measurements and blood sampling. Two proteomic assays (Olink Proseek(R)Inflammation panel and Olink Proseek(R)Cardiovascular II panel), each measuring 92 proteins, were analysed in a subsample of 253 women.p-Values were adjusted for multiple testing, with false discovery rate set at 10%. In unadjusted models, 57 proteins were associated with apnea-hypopnea index, 56 proteins with oxygen desaturation index and 64 proteins with rapid eye movement-apnea-hypopnea index. After adjustment for age, body mass index and plate, there were no significant associations between apnea-hypopnea index or oxygen desaturation index and any of the proteins. Severe obstructive sleep apnea during rapid eye movement sleep (rapid eye movement-apnea-hypopnea index >= 30) was associated with decreased levels of two anti-inflammatory proteins; Sirt2 (q-value .016) and LAP-TGF-beta(1)(q-value .016). There was also a negative association between rapid eye movement-apnea-hypopnea index of >= 30 and Axin1 (q-value .095), a protein thought to facilitate TGF-beta-signalling. We conclude that severe obstructive sleep apnea during rapid eye movement sleep is associated with low levels of Sirt2, LAP-TGF-beta(1)and Axin1, anti-inflammatory proteins involved in metabolic regulation and in the atherosclerotic process. For obstructive sleep apnea based on a whole night, the associations with cardiac and inflammatory proteins are weaker, and explained to a large extent by age and body mass index.

Research in sleep medicine over the last decades has involved a broad variety of sleep disorders in both men and women. Gender differences have been identified in sleep physiology as well as in the three most common sleep disorders: obstructive sleep apnoea (OSA), insomnia and restless legs syndrome (RLS). However, research on gender differences in sleep medicine appears limited. This clinical review aims to give an updated overview of gender differences, in relation to prevalence, clinical presentation, treatment and quality of life in OSA, insomnia and RLS. Future research directions in the adult population will also be discussed.

Introduction Insomnia disorder has a very weak link to polysomnography (PSG) and so does sleep problems in the general population. The reason for this is not clear. One possibility is that the perception of disturbed sleep may be related to immune activation or anxiety/depression, without impairment of objective sleep. Methods 400 women participated, constituting a representative sample of the city of Uppsala with oversampling of snorers. Insomniacs (N=41) were compared with normal sleepers in terms of polysomnography (PSG), immune parameters, anxiety and depression Results The results (after adjustment for age and BMI) show that C-reactive protein (CRP) reached a higher level (4.4±.5) in insomniacs (vs 2.3±.2 for normal sleepers) (p=.003) and lower subjective health (p=.000), while anxiety (p=.000) and depression (p=.000) (Hospital Anxiety and Depression Scale (HAD)) showed higher levels. PSG sleep continuity variables lacked association with insomnia, as did all sleep stage variables except for REM%, with a lower level in the insomnia group (p=.021). Interleukin 6 and Tumor Necrosis Factor alpha were not related to insomnia. CRP levels did not correlate significantly with anxiety or depression, but with subjective health (r=-.21, p=.000). A logistic regression analysis (excluding the variable subjective health) with insomnia as outcome (0/1) yielded as predictors CRP (OR=1.14, Ci= 1.05; 1.24, p=.000), depression (OR=1.21, Ci=1.06;1.38, p=.000) and anxiety (OR=1.15, Ci=1.02;1.30, p=.021). Conclusion It was concluded that increased CRP levels may be part of the subjective experience of insomnia. Support No external funding

Background Subarachnoid haemorrhage (SAH) is a devastating disease, with high mortality rate and substantial disability among survivors. Its causes are poorly understood. We aimed to investigate risk factors for SAH using a novel nationwide cohort consortium. Methods We obtained individual participant data of 949 683 persons (330 334 women) between 25 and 90 years old, with no history of SAH at baseline, from 21 population-based cohorts. Outcomes were obtained from the Swedish Patient and Causes of Death Registries. Results During 13 704 959 person-years of follow-up, 2659 cases of first-ever fatal or non-fatal SAH occurred, with an age-standardized incidence rate of 9.0 [95% confidence interval (CI) (7.4–10.6)/100 000 person-years] in men and 13.8 [(11.4–16.2)/100 000 person-years] in women. The incidence rate increased exponentially with higher age. In multivariable-adjusted Poisson models, marked sex interactions for current smoking and body mass index (BMI) were observed. Current smoking conferred a rate ratio (RR) of 2.24 (95% CI 1.95–2.57) in women and 1.62 (1.47–1.79) in men. One standard deviation higher BMI was associated with an RR of 0.86 (0.81–0.92) in women and 1.02 (0.96–1.08) in men. Higher blood pressure and lower education level were also associated with higher risk of SAH. Conclusions The risk of SAH is 45% higher in women than in men, with substantial sex differences in risk factor strengths. In particular, a markedly stronger adverse effect of smoking in women may motivate targeted public health initiatives.

Background: Proteomic-based technologies offer new possibilities to identify altered levels of cardiac and inflammatory proteins that might reflect the cardiometabolic stress caused by different measures of OSA. Aim: To investigate the effects of OSA on the cardiovascular system by analysing a broad panel of cardiac and inflammatory proteins in relationship to different measures of OSA in a population based cohort of women. Method: In the “Sleep and Health in Women” (SHE) cohort study, 400 women underwent polysomnography, anthropometric measurements and blood sampling. Two proteomic assays (Olink Proseek® Inflammation panel and Cardiovascular II panel), each measuring 92 proteins, were analysed in a subsample of 253 women. Results: In unadjusted models, with false discovery rate set to 10%, 57 proteins were associated with AHI, 56 proteins with ODI and 64 proteins with REM AHI. After adjustment for age, BMI and plate there were no significant associations between AHI or ODI and any of the proteins. REM AHI>30 was associated with decreased levels of two proteins involved in anti-inflammatory processes; Sirt2 (q-value 0.016) and LAP-TGFs1 (q-value 0.016). There was further a negative association between REM AHI>30 and Axin1 (q-value 0.095), a protein known to facilitate TGFs signalling. Conclusion: Severe OSA during REM sleep affected the plasma levels of Sirt2, LAP-TGFs1 and Axin1. For overall AHI and ODI the associations with cardiac and inflammatory proteins were weaker and to a large extent explained by age and BMI.

There is a lack of studies on the association between total sleep time (TST) and other polysomnographical parameters. A key question is whether a short sleep is an expression of habitual short sleep, or whether it reflects temporary impairment. The purpose of the present study was to investigate the association between TST and amount of sleep stages and sleep continuity measures, in a large population‐based sample of women (n = 385), sleeping at home in a normal daily life setting. The results show that sleep efficiency, N1 (min), N2 (min), REM (min), REM% and proportion of long sleep segments, increased with increasing TST, whereas the number of awakenings/hr, the number of arousals/hr, N1% and REM intensity decreased. In addition, longer sleep was more associated with TST being perceived as of “usual” duration and with better subjective sleep quality. TST was not associated with habitual reported sleep duration. It was concluded that short TST of a recorded sleep in a real‐life context may be an indicator of poor objective sleep quality for that particular sleep episode. Because individuals clearly perceived this reduction, it appears that self‐reports of poor sleep quality often may be seen as indicators of poor sleep quality. It is also concluded that PSG‐recorded sleep duration does not reflect habitual reported sleep duration in the present real‐life context.

An association between obstructive sleep apnea and the incidence of heart failure has been reported in men but not in women. The aim of this study was to investigate whether a combination of snoring and excessive daytime sleepiness, the two main symptoms of obstructive sleep apnea syndrome, was able to predict incident heart failure in a population-based sample of women.The population-based cohort study Sleep and Health in Women (SHE; n = 5990 women born between 1901 and 1980) was used, with baseline questionnaire data from April 2000 relating to snoring, excessive daytime sleepiness, and covariates. Using data retrieved from the Swedish National Patient Register and Cause of Death Register, the follow-up of incident heart failure continued until 31 December 2011.Among women with both snoring and excessive daytime sleepiness at baseline, 5.3% developed heart failure during follow-up compared with 0.9% in the reference group with neither snoring nor excessive daytime sleepiness. After adjustment for age, waist circumference, smoking, alcohol, hypertension, diabetes, previous myocardial infarction, physical inactivity, depressive symptoms, menopausal status, and hormone replacement therapy, women with the combination of snoring and excessive daytime sleepiness had a twofold increase in the risk of incident heart failure (hazard ratio [HR] 2.2 95% confidence interval [CI] 1.1-4.4).Symptoms of obstructive sleep apnea, that is, the combination of snoring and excessive daytime sleepiness, are associated with an increased risk of developing heart failure in women.

Although obstructive sleep apnea (OSA) is associated with overall cardiovascular disease and mortality, the association with atherosclerotic cardiovascular disease is less clear, especially in women. Recently, it has been suggested that OSA during rapid eye movement (REM) sleep, associated with long apneas and deep desaturations, could have severe cardiometabolic consequences. The aim of this study was to investigate whether OSA during REM sleep is associated with early signs of atherosclerosis in a population-based sample of women.In the community-based "Sleep and Health in Women" (SHE) cohort study, 400 women underwent polysomnography, anthropometric measurements, blood sampling, blood pressure measurement, and answered questionnaires. Ten years later, 201 of the original participants, free of known atherosclerotic disease at baseline and without continuous positive airway pressure treatment for OSA, underwent a high-frequency ultrasound of the common carotid artery to assess the individual thickness of the layers of the artery wall.Severe OSA during REM sleep (REM apnea-hypopnea index [AHI] ≥ 30) was associated with a thicker intima. This association was still significant after adjustment for age, body mass index, alcohol, and smoking, as well as for further adjustment for systolic blood pressure, low-density lipoprotein, C-reactive protein, and diabetes (β-coefficient, 0.008; p-value, 0.022). The association between a REM AHI of ≥30 and intima thickness was also seen in women with no or mild OSA and normal non-REM AHI.In this study of a community-based sample of women, severe OSA during REM sleep was independently associated with early signs of atherosclerosis.

Background Hand hygiene compliance is the basis of infection control programs. In developing countries models to improve hand hygiene compliance to reduce healthcare acquired infections are required. The aim of this study was to determine hand hygiene compliance following an educational program in an obstetric and gynecological hospital in Vietnam. Methods Health care workers from neonatal intensive care, delivery suite and a surgical ward from Hung Vuong Hospital, Ho Chi Minh City, Vietnam undertook a 4-h educational program targeting hand hygiene. Compliance was monitored monthly for six months following the intervention. Hand hygiene knowledge was assessed at baseline and after six months of the study. Results There were 7124 opportunities over 370 hand hygiene recording sessions with 1531 opportunities at baseline and 1620 at 6 months following the intervention. Hand hygiene compliance increased significantly from baseline across all sites (43.6% [95% Confidence interval CI: 41.1–46.1] to 63% [95% CI: 60.6–65.3]; p

Objective Previous studies have shown that both sleep duration and insomnia have an impact on obesity and central obesity. However, studies of the joint effects of these sleep disorders are still sparse. Methods The present study utilized data from the Swedish EpiHealth cohort study. Participants (45–78 y) were asked to fill out an internet-based questionnaire. Body mass index (BMI) and central obesity (calculated from waist circumference) were based on measured data. Results A total of 18,823 participants (mean age = 60 ys) were included in this study. The reported prevalence of short ( 9 h/night) sleep duration was 8% and 4% respectively, and insomnia symptoms was 19%. Of the study population, 16% were obese (BMI ≥ 30 kg/m 2 ) and 40% had central obesity. There was a U-shaped association between sleep duration and obesity and central obesity, and significant associations between insomnia symptoms and obesity. When stratifying sleep duration by concurrent insomnia symptoms, there were associations (odds ratios, (95% confidence intervals)) between the combination of both short (1.48, (1.22–1.80)) and long sleep duration (1.77 (1.00–3.16)) with insomnia symptoms and obesity and central obesity (1.36 (1.16–1.61) and 2.44 (1.41–3.24) respectively). However, there was no significant association between insomnia symptoms and obesity or central obesity in participants with normal sleep duration. For central obesity there was an association with long sleep duration regardless of insomnia symptoms, while the association with short sleep duration was significant only if insomnia symptoms were present. Conclusions Both short and long sleep duration, as well as insomnia symptoms, are associated with obesity and central obesity. There is an important joint effect of sleep duration and insomnia symptoms and there is no association between insomnia symptoms and obesity, as long as a normal sleeping time can be attained. This indicates that sleep duration rather than insomnia symptoms per se is of importance for the relationship between sleep and obesity.

The aim of the study was to analyse the impact of self-reported nasal obstruction on sleep quality in women. A community-based sample of 400 women underwent a full night of polysomnography. Airway diseases, allergies and sleep-related symptoms were assessed by questionnaires. Women with subjective nasal obstruction were subdivided into three groups: persistent nasal obstruction (PNO, n = 46), hay fever (n = 88) and nasal obstruction at night (NON, n = 30). Sleep problems and related daytime symptoms were most prevalent among women with NON. After adjusting for age, BMI, smoking and asthma, NON was an independent predictor of 'Difficulties inducing sleep due to nasal obstruction' [adjusted odds ratio (95 % CI): 89.5 (27.0-296.7)], 'Snoring' [4.2 (1.7-10.2)], 'Sweating at night' [2.6 (1.1-6.1)], 'Difficulties maintaining sleep' [2.7 (1.2-6.2)], and 'Waking up hastily gasping for breath' [32.2 (8.7-119.1)]. 'Dry mouth on awakening' [7.7 (3.2-18.4)], 'Waking up unrefreshed' [2.7 (1.2-6.0)], 'Excessive daytime sleepiness' [2.6 (1.1-6.0)], and 'Daytime nasal obstruction' [12.2 (4.8-31.2)] were also associated with NON. Persistent nasal obstruction and hay fever were both associated with some reported sleep problems due to an overlap with NON. When women with NON were excluded, only 'Daytime nasal obstruction' was still significantly associated with PNO, while hay fever was associated with 'Daytime nasal obstruction' and 'Waking up hastily gasping for breath'. There were no significant differences in objectively measured sleep variables between any of the three subgroups and the study cohort. Self-reported nasal obstruction at night in women has a significant effect on several subjective day- and nighttime symptoms, but it does not appear to affect objectively measured sleep quality.

Background It has been suggested that sleep-disordered breathing (SDB) is a risk factor for diabetes, but long-term follow-up studies are lacking. The aim of this community-based study was to analyze the influence of SDB on glucose metabolism after > 10 years. Methods Men without diabetes (N = 141; mean age, 57.5 years) were investigated at baseline, including whole-night respiratory monitoring. After a mean period of 11 years and 4 months, they were followed up with an interview, anthropometric measurements, and blood sampling. Insulin resistance was quantified using the homeostasis model assessment of insulin resistance (HOMA-IR). ΔHOMA-IR was calculated as (HOMA-IR at follow-up − HOMA-IR at baseline). An oral glucose tolerance test was performed on 113 men to calculate the insulin sensitivity index. Results The mean apnea-hypopnea index (AHI) and oxygen desaturation index (ODI) at baseline were 4.7 and 3.3, respectively. At follow-up, 23 men had diabetes. An ODI > 5 was a predictor of developing diabetes (OR, 4.4; 95% CI, 1.1-18.1, after adjusting for age, BMI, and hypertension at baseline and ΔBMI and years with CPAP during follow-up). The ODI was inversely related to the insulin sensitivity index at follow-up (r = −0.27, P = .003). A deterioration in HOMA-IR was significantly related to all variables of SDB (AHI, AHI > 5; ODI, ODI > 5; minimum arterial oxygen saturation), even when adjusting for confounders. When excluding the variable years with CPAP from the multivariate model, all associations weakened. Conclusions SDB is independently related to the development of insulin resistance and, thereby, the risk of manifest diabetes mellitus.

Summary It is well known that the quantity and quality of physiological sleep changes across age. However, so far the effect of age on sleep microstructure has been mostly addressed in small samples. The current study examines the effect of age on several measures of sleep macro- and microstructure in 211 women (22–71 years old) of the ‘Sleep and Health in Women’ study for whom ambulatory polysomnography was registered. Older age was associated with significantly lower fast spindle (effect size f2 = 0.32) and K-complex density (f2 = 0.19) during N2 sleep, as well as slow-wave activity (log) in N3 sleep (f2 = 0.21). Moreover, total sleep time (f2 = 0.10), N3 sleep (min) (f2 = 0.10), rapid eye movement sleep (min) (f2 = 0.11) and sigma (log) (f2 = 0.05) and slow-wave activity (log) during non-rapid eye movement sleep (f2 = 0.09) were reduced, and N1 sleep (f2 = 0.03) was increased in older age. No significant effects of age were observed on slow spindle density, rapid eye movement density and beta power (log) during non-rapid eye movement sleep. In conclusion, effect sizes indicate that traditional sleep stage scoring may underestimate age-related changes in sleep.

Collectively, cross-sectional and longitudinal studies on self-reported sleep duration and obesity do not show a clear pattern of association with some showing a negative linear relationship, some showing a U-shaped relationship, and some showing no relationship. Associations between sleep duration and obesity seem stronger in younger adults. Cross-sectional studies using objectively measured sleep duration (actigraphy or polysomnography (PSG)) also show this mixed pattern whereas all longitudinal studies to date using actigraphy or PSG have failed to show a relationship with obesity/weight gain. It is still too early and a too easy solution to suggest that changing the sleep duration will cure the obesity epidemic. Given novel results on emotional stress and poor sleep as mediating factors in the relationship between sleep duration and obesity, detection and management of these should become the target of future clinical efforts as well as future research.

The study was financially supported by the Swedish Heart and Lung Foundation and the Swedish Association against Heart and Lung Diseases.

To assess characteristics of short sleepers and long sleepers and to assess association between sleep duration and central obesity in a population-based sample of women.Non-pregnant women ≥20 years that were randomly selected from the population-registry of Uppsala, Sweden, answered a questionnaire (n=6461) including questions on sleeping habits and somatic disorders.There was a U-shaped association between sleep duration and waist circumference. Short sleeping women (5 h) had a waist circumference of 89.2±14.9 cm (mean±SD) decreasing to 82.9±11.9 cm for women sleeping 7-8 h and increasing to 89.0±16.7 cm for women sleeping ≥10 h. Both short sleepers and long sleepers were more often physically inactive, smokers, ill or taking medication, and psychologically distressed than normal sleepers (6-9 h). In women50 years both short and long sleep duration were risk factors for central obesity. Short sleep duration remained a risk factor for central obesity, whereas the association with long sleep duration did not reach statistical significance after adjustments.Short sleepers and long sleepers showed differences in characteristics compared to normal sleepers. Furthermore, we showed an independent association between short sleep duration and central obesity, which was strongest in younger women. It is important to identify short sleepers, especially in younger women.

Women complain more about sleep than men, but polysomnography (PSG) seems to suggest worse sleep in men. This raises the question of how women (or men) perceive objective (PSG) sleep. The present study sought to investigate the relation between morning subjective sleep quality and PSG variables in older and younger women. A representative sample of 251 women was analysed in age groups above and below 51.5 years (median). PSG was recorded at home during one night. Perceived poor sleep was related to short total sleep time (TST), long wake within total sleep time (WTSP), low sleep efficiency and a high number of awakenings. The older women showed lower TST and sleep efficiency and higher WTSP for a rating of good sleep than did the younger women. For these PSG variables the values for good sleep in the older group were similar to the values for poor sleep in the young group. It was concluded that women perceive different levels of sleep duration, sleep efficiency and wake after sleep onset relatively well, but that older women adjust their objective criteria for good sleep downwards. It was also concluded that age is an important factor in the relation between subjective and objective sleep.

Young women with short sleep duration and insomnia run a high risk of developing hypertension and diabetes mellitus : A 10-year follow-up of the population-based SHE study

The aim of this study was to assess associations between obstructive sleep apnea (OSA) and metabolic syndrome in a population-based sample of women.Four hundred women aged 20-70 years underwent a full-night polysomnography, fasting blood sampling and measurement of anthropometric variables. Metabolic syndrome was defined according to the National Cholesterol Education Program (NCEP) criteria.The NCEP criteria of metabolic syndrome were fulfilled by 104 (26.0%) of the women. The frequency of metabolic syndrome increased from 10.5% in women with apnea-hypopnea-index (AHI)5 to 57.1% in women with AHI ≥30 (p for trend0.0001). In the multivariate analysis, the severity of OSA measured as AHI, ODI (oxygen desaturation index), minimal saturation or T(90) (percentage of time during night with saturation90%) were associated with metabolic syndrome after adjustment for age, level of physical activity, smoking and alcohol consumption. AHI (adj. OR 1.45; 95% CI 1.11-1.91), ODI (1.37; 1.09-1.73) and minimal saturation level (0.93; 0.87-0.99) remained significantly associated with metabolic syndrome also when adjusting for the waist-to-hip-ratio. The three markers of OSA were independently associated with central obesity, hypertriglyceridemia and reduced HDL cholesterol concentration.Measures of OSA were closely associated with metabolic syndrome and its components in this population-based sample of women also after adjustments. Therefore, when the health consequences of sleep-disordered breathing are investigated it is important to consider metabolic syndrome. Sleep-disordered breathing should also be considered when treating patients with metabolic syndrome.

Study Objectives: Obesity is often associated with impaired sleep, whereas the impact of body mass index (BMI) at younger age and previous weight gain on sleep problems remains unknown. Methods: The present study utilized data from the Swedish EpiHealth cohort study. A total of 15845 participants (45–75 years) filled out an internet-based questionnaire. BMI was calculated from both measured data at study time and self-reported data at age 20 from the questionnaire. Results: Sleep-related symptoms were most common among obese individuals (BMI > 30 kg/m2). An association between weight gain and sleep problems was found and those with a low BMI at age 20 were most vulnerable to weight gain when it came to risk of sleep problems. Among those who were underweight (BMI < 18.5 kg/m2) at age 20, weight gain (kg/year) was associated with difficulties initiating sleep with an adjusted OR of 2.64 (95% CI: 1.51–4.62) after adjusting for age, sex, smoking, alcohol consumption, physical activity, education, and civil status. The corresponding adjusted OR’s among those who had been normal weight (BMI 18.5–24.99) and overweight (BMI 25–29.99 kg/m2) at age 20 were 1.89 (1.47–2.45) and 1.02 (0.48–2.13), respectively. Also difficulties maintaining sleep and snoring were most strongly related to weight gain among those who were underweight at age 20 with decreasing odds with increasing BMI at that age. Conclusions: Sleep problems are related to weight gain and obesity. The impact of weight is most pronounced among those who had a low BMI when young. (Less)

Factors influencing compliance to continuous positive airway pressure treatment in obstructive sleep apnea and mortality associated with treatment failure

Chronic rhinosinusitis is an independent risk factor for sleeping problems – a 10-year-follow-up study

The change in sleepiness across 10 years of aging and its relation to changes in polysomnographic variables