The role of obstructive sleep apnea in metabolic syndrome: A population-based study in women

Does obstructive sleep apnea increase the risk of cancer and cancer mortality in combined community-based cohorts?

Obstructive sleep apnea (OSA) has been linked to cancer in several clinical and community-based cohorts. The effect in community-based studies free of clinical referral bias needs to be replicated. In this observational prospective cohort study, we pooled data from three community-based prospective cohorts (Uppsala Sleep and Health in Men cohort [UMEN]; Sleep and health in women [SHE]; Men Androgen Inflammation Lifestyle Environment and Stress Cohort [MAILES]; nTotal = 1467). All cohorts had objective data on obstructive sleep apnea and registry linkage data on cancer and cancer mortality. Analyses for different obstructive sleep apnea measures (apnea-hypopnea index [AHI], oxygen desaturation index [ODI], and minimal saturation) as risk factors for cancer incidence (all cancers) were performed using Cox proportional hazards models (follow-up 5-16 years). We did not find an overall increased risk of cancer after adjustment for age, sex, and BMI (HRAHI [95% CI] = 1.00 [0.98; 1.01] and HRODI [95% CI] = 0.99 [0.97; 1.01]). Stratifying by daytime sleepiness did not influence the association. Cancer mortality was not significantly associated with obstructive sleep apnea. Taken together, we did not observe an overall increased risk of cancer or cancer mortality in relation to obstructive sleep apnea, however, our confidence limits remain wide for important diagnostic categories of sleep apnea severity. The relationship between obstructive sleep apnea and cancer needs further investigation in a comprehensive multi-cohort approach with greater statistical precision. For future studies we may need to find and then combine every community-based cohort study that can provide a definitive answer to the question on the risk of cancer from obstructive sleep apnea in the general population.

Lifestyle patterns, nutritional, and metabolic syndrome determinants in a sample of the older Iranian population

BACKGROUND

Chronic diseases and metabolic disorders are prevalent health concerns that often escalate with increasing age and thus affect older individuals. The proportion of the elderly population in Iran increased from 7.22% in 2006 to 12.0% in 2023. The current study aimed to evaluate lifestyle patterns and lifestyle risk factors among patients with metabolic syndrome (MetS) based on dietary, physical activity, and smoking, as well as MetS components.

METHODS

This cross-sectional study included 582 older people with MetS living in Yazd, Iran. Latent class analysis (LCA) was used to determine the lifestyle behaviors of diet patterns, smoking, and physical activity. Dietary intake was measured using a validated food frequency questionnaire, and dietary patterns were identified using principal component analysis (PCA). Clinical measurements of MetS components were examined using relevant guidelines.

RESULTS

The mean age of the participants was 72.71 years (SD = 5.57). Using PCA, two dietary patterns were identified: traditional patterns (e.g., fruits, fish, poultry, vegetables, meats, salt, and sugar sweetened beverages) and high-fat patterns (e.g., high-fat dairy). Applying LCA identified two classes of lifestyle patterns. About 35% (n = 204) of the participants were categorized in a low-risk class (I) and characterized by physical activity (0.93%, n = 190), a traditional pattern for diet (61%, n = 122), and zero probability of smoking. About 65% (n = 378) of the patients were categorized in high-risk class (II) and characterized by low physical activity levels (69%, n = 261), cigarette smoking (71.6%, n = 271), and a high-fat dietary pattern (56.9%, n = 215).

CONCLUSION

The results of our study indicated two distinct classes within the patients. In class I, aging patients with MetS exhibited characteristics such as engagement in physical activity and having a traditional pattern for diet. Class II, with a higher prevalence of lifestyle risk factors, included individuals who engaged in cigarette smoking, displayed low physical activity (69%), and having a high-fat diet. The combination of these lifestyle factors exposed them to a heightened risk of developing MetS. The findings could guide healthcare professionals to be aware of the associations between different lifestyle risk factors and to focus on multiple behaviors at the same time.

A Review of Novel Oximetry Parameters for the Prediction of Cardiovascular Disease in Obstructive Sleep Apnoea

Obstructive sleep apnoea (OSA) is a sleep disorder with repetitive collapse of the upper airway during sleep, which leads to intermittent hypoxic events overnight, adverse neurocognitive, metabolic complications, and ultimately an increased risk of cardiovascular disease (CVD). The standard diagnostic parameter for OSA, apnoea-hypopnoea index (AHI), is inadequate to predict CVD morbidity and mortality, because it focuses only on the frequency of apnoea and hypopnoea events, and fails to reveal other physiological information for the prediction of CVD events. Novel parameters have been introduced to compensate for the deficiencies of AHI. However, the calculation methods and criteria for these parameters are unclear, hindering their use in cross-study analysis and studies. This review aims to discuss novel parameters for predicting CVD events from oximetry signals and to summarise the corresponding computational methods.

Relationship between obstructive sleep apnea, insulin resistance, and metabolic syndrome: a nationwide population-based survey

We aimed to identify the association between obstructive sleep apnea (OSA), insulin resistance (IR), and metabolic syndrome (MetS) in a nationwide population-based sample. A total of 7,900 adults with information on the STOP-Bang score and MetS (3,341 men and 4,469 women) were identified from the dataset of the Korea National Health and Nutrition Examination Survey 2019-2020. The association between OSA, IR, MetS, and its components was estimated using complex sample logistic regression analysis with adjustments for age, body mass index, residence, smoking status, alcohol consumption, household income, education, and the presence of diabetes. Participants with a high OSA score were more likely to have IR (odds ratio [OR] 2.78, 95% confidence interval [CI] 1.96-3.95 in men and OR 2.64, 95% CI 0.55-12.80 in women), MetS (OR 6.05, 95% CI 4.23-8.69 in men and OR 4.20, 95% CI 1.23-15.70 in women), and components of MetS, compared to individuals with a low OSA score. Compared to premenopausal women, postmenopausal women had a more intense association between OSA and IR (OR 1.78, 95% CI 0.13-24.43 for premenopausal women and OR 3.64, 95% CI 0.60-22.28 for postmenopausal women) and MetS (OR 2.58, 95% CI 0.23-29.55 for premenopausal women and OR 5.36, 95% CI 1.42-20.21 for postmenopausal women). OSA was associated with abdominal obesity and hypertension in premenopausal women, while all components of MetS were associated with OSA in postmenopausal women. Further studies are necessary to elucidate the underlying mechanisms of these findings.

Effects of a palaeolithic diet on obstructive sleep apnoea occurring in females who are overweight after menopause—a randomised controlled trial

Background/Objectives

Obesity is the main risk factor for obstructive sleep apnoea, commonly occurring in females who are overweight after menopause. We aimed to study the effect of a palaeolithic diet on sleep apnoea in females with overweight after menopause from the population.

Methods

Seventy healthy, non-smoking females with a mean age of 60 years and a mean BMI of 33 kg/m2 were randomised to a palaeolithic diet or to a control low-fat diet according to Nordic Nutritional Recommendations, for 2 years. The apnoea-hypopnoea index was measured and daytime sleepiness was estimated during the intervention.

Results

The mean apnoea-hypopnoea index at baseline was 11.6 (95% CI 8.6–14.5). The mean weight loss was 7.2 kg (95% CI 5.3–9.2 kg) in the palaeolithic diet group and 3.9 kg in the control group (95% CI 1.9–5.9 kg); p < 0.021 for the group difference. The reduction in weight corresponded to a reduction in the apnoea-hypopnoea index in the palaeolithic diet group (r = 0.38, p = 0.034) but not in the control group (r = 0.08, p = 0.69). The apnoea-hypopnoea index was reduced in the palaeolithic diet group when the weight was reduced by more than 8 kg. Daytime sleepiness according to the Epworth Sleepiness Scale score and the Karolinska Sleepiness Scale score was unaffected by dietary group allocation.

Conclusions

A substantial decrease in body weight of 8 kg was needed to achieve a reduction in sleep apnoea in this small trial of women who are overweight after menopause. The palaeolithic diet was more effective for weight reduction than a control low-fat diet and the reduction in sleep apnoea was related to the degree of weight decrement within this diet group.

Trial registration

Clinicaltrials.gov: NCT00692536.

Impact of obstructive sleep apnea on cardiometabolic health in a random sample of older adults in rural South Africa: building the case for the treatment of sleep disorders in underresourced settings

STUDY OBJECTIVES

The association between obstructive sleep apnea (OSA) and increased cardiometabolic risk (CMR) has been well documented in higher-income countries. However, OSA and its association with CMR have not yet been investigated, based on objective measures, in southern Africa. We measured polysomnography-derived sleep characteristics, OSA prevalence, and its association with cardiometabolic diseases in a rural, low-income, African-ancestry sample of older adult participants in South Africa.

METHODS

Seventy-five participants completed the study. Body mass index, hypertension, diabetes, dyslipidemia, and HIV status were determined. A continuous CMR score was calculated using waist circumference, random glucose, high-density-lipoprotein cholesterol, triglycerides, and mean arterial blood pressure. Sleep architecture, arousal index, and apnea-hypopnea index for detection of the OSA (apnea-hypopnea index ≥ 15 events/h) were assessed by home-based polysomnography. Associations between CMR score and age, sex, socioeconomic status, apnea-hypopnea index, and total sleep time were investigated by multivariable analysis.

RESULTS

In our sample (53 women, age 66.1 ± 10.7 years, 12 HIV+), 60.7% of participants were overweight/obese, 61.3% were hypertensive, and 29.3% had undiagnosed OSA. Being older (P = .02) and having a higher body mass index (P = .02) and higher waist circumference (P < .01) were associated with OSA. Apnea-hypopnea index severity (β = 0.011; P = .01) and being a woman (β = 0.369; P = .01) were independently associated with a higher CMR score in socioeconomic status- and age-adjusted analyses.

CONCLUSIONS

In this South African community with older adults with obesity and hypertension, OSA prevalence is alarming and associated with CMR. We show the feasibility of detecting OSA in a rural setting using polysomnography. Our results highlight the necessity for actively promoting health education and systematic screening and treatment of OSA in this population to prevent future cardiovascular morbidity, especially among women.

Prevalence of metabolic syndrome in patients with rheumatoid arthritis in eastern China-A hospital based study

OBJECTIVE

The purpose of this hospital clinic based study was to evaluate the potential risk factors associated with the prevalence of MetS in RA population.

METHODS

From January 2015 to October 2018, 717 patients with RA and 717 healthy controls who were treated or performed physical examination in Tianjin First Central Hospital were enrolled in this study. The basic disease diagnoses were recorded. A questionnaire was performed on all participants to assess the demographic details of the RA cohort. Moreover, laboratory indicators related to glucose and lipid metabolism in patients with RA were also detected. The potential risk factors for MetS were also analyzed.

RESULTS

The prevalence of MetS were 31.2% and 34.2% in case and control groups, respectively (P = .22). There were lower levels of HDL-C, obesity, TG, LDL-C and TC in case group than control group (all P < .05). The hypertension levels in healthy controls was decreased in compared with patients with RA (P < .05). Nevertheless, in patients with RA, complement 3 (OR: 1.02; 95% CI: 1.01-1.03, P = .007) and less glucocorticoids use (OR: 0.63, 95% CI: 0.39-0.99, P = .046) were associated with MetS.

CONCLUSION

The prevalence of MetS was not associated with RA. Complement 3 may be associated with the higher prevalence of MetS in patients with RA. Glucocorticoids treatment may be associated with MetS.

Examination of the Relationship Between Metabolic Syndrome and Obstructive Sleep Apnea in Iranian Patients with Type 2 Diabetes: A Case-Control Study

INTRODUCTION

Obstructive sleep apnea (OSA) is a common risk factor for metabolic syndrome (MS) that increases the chance of cardiovascular disease, stroke, and mortality. Many studies have been conducted on this matter, but the results are still conflicting. The aim of the present study was to examine the relationship between metabolic syndrome (MS) and obstructive sleep apnea (OSA) in Iranian patients with type 2 diabetes (T2D).

PATIENTS AND METHODS

This matched case-control study was conducted with 190 patients with T2D in Sanandaj, Iran. The data were selected using the demographic questionnaire, clinical and anthropometric measures, the Berlin Questionnaire (BQ), and the National Cholesterol Education Program's Adult Treatment Panel III (NCEP-ATP III). Participants were divided into two groups of high risk of OSA (experimental) and low risk of OSA (control). The data were analyzed using Stata, version 14.

RESULTS

The frequency of MS was higher in the OSA group than the control group (81.1% vs 70.5%), but the group difference was not statistically significant (p=0.127). The results of crude and age-sex adjusted logistic regression analysis revealed no significant association between OSA and the other variables under study (P>0.05). Sensitivity analysis and external adjustment for BMI showed no significant relationship between OSA and the other variables under study (P=0.319).

CONCLUSION

In the present study, no significant association was found between metabolic syndrome (MS) and obstructive sleep apnea (OSA) in patients with T2D; therefore, more studies should be conducted on this subject.

Effect of Three Hypopnea Scoring Criteria on OSA Prevalence and Associated Comorbidities in the General Population

STUDY OBJECTIVES

Apnea-hypopnea index (AHI) is the main polysomnographic measure to diagnose obstructive sleep apnea (OSA). We aimed to evaluate the effect of three standard hypopnea definitions on the prevalence of OSA and its association with cardiometabolic outcomes in the general population.

METHODS

We analyzed data from the HypnoLaus study (Lausanne, Switzerland), in which 2,162 participants (51% women, 57 ± 19 years) underwent in-home full polysomnography. AHI was calculated using three hypopnea definitions: AASM₁₉₉₉ (≥ 50% decrease in airflow or lower airflow reduction associated with oxygen desaturation ≥ 3% or an arousal), AASM₂₀₀₇ (≥ 30% airflow reduction associated with ≥ 4% oxygen desaturation), and AASM_{2012 (≥} 30% airflow reduction associated with ≥ 3% oxygen desaturation or an arousal). Participants underwent clinical assessment for hypertension, diabetes, and metabolic syndrome.

RESULTS

Median AHI of AASM₁₉₉₉, AASM₂₀₀₇ and AASM₂₀₁₂ criteria were 10.9, 4.4, and 10.1 events/h, respectively. OSA prevalence defined as AHI ≥ 5, ≥ 15, and ≥ 30 events/h was 74.5%, 39.3%, and 16.3% using AASM₁₉₉₉; 46.9%, 18.8%, and 6.8% using AASM₂₀₀₇; and 72.2%, 36.6%, and 14.9% using AASM₂₀₁₂. Different AHI thresholds derived from AASM₁₉₉₉, AASM₂₀₀₇, and AASM₂₀₁₂ criteria_, respectively, were associated with hypertension (11.5, 4.8, 10.7 events/h), diabetes (15.7, 7.1, 14.4 events/h), and metabolic syndrome (12.8, 5.5, 11.8 events/h).

CONCLUSIONS

Hypopnea definition has a major effect on AHI and on OSA prevalence in the general population and, hence, important implications for public health policies. There is a twofold difference in the threshold above which an association with diabetes, hypertension, and metabolic syndrome is observed using AASM₂₀₀₇ compared to AASM₁₉₉₉ or AASM₂₀₁₂ criteria.

Obesity metabolic and hormonal disorders associated with obstructive sleep apnea and their impact on the risk of cardiovascular events

OBJECTIVE

To analyze metabolic and hormonal disorders resulting from the association between obesity and obstructive sleep apnea (OSA) syndrome that predispose to cardiovascular diseases and investigate the clinical benefits obtained from treatment approaches for both conditions.

METHODS

A literature review between 1997 and 2017 was conducted in the PubMed search database.

RESULTS

Obesity is the most important risk factor for OSA, and the progressive increase in its prevalence also affects OSA incidence. In addition, OSA may aggravate weight gain and obesity comorbidities. Both conditions lead to an increase in the risk of cardiovascular events and mortality. The gold standard treatment for moderate to severe OSA is CPAP, but significant reduction in major cardiovascular events was not observed in clinical trials. Body weight reduction appears effective to improve OSA, as long as it is maintained. Lifestyle modifications and drug therapy seem to be the preferred approach to treat obesity, but in severe obesity and moderate to severe OSA, bariatric surgery is probably the most adequate treatment.

CONCLUSIONS

Weight control is essential to decrease the risk of cardiovascular events and mortality potentially linked to both obesity and OSA. CPAP seems to treat only OSA without decreasing these risks. Other treatment strategies are lifestyle modifications and drug therapy, which need further investigation as well as bariatric surgery for severe cases.

Associations Between the Prevalence of Metabolic Syndrome and Sleep Parameters Vary by Age

OBJECTIVE

To examine whether the relationship between the metabolic syndrome (MetS) and various sleep parameters [sleep duration, symptoms of sleep-disordered breathing (SDB), and sleep disturbances] varies by age.

METHODS

Waist circumference, blood pressure, triglycerides, high-density lipoprotein cholesterol, and fasting glucose were used to determine MetS status in a cohort (N = 19,691) of middle-aged (aged 45-64 years) and older (aged ≥65 years) subjects. Habitual sleep duration (short, ≤6 h/day; normal, 7-8 h/day; and long ≥9 h/day), sleep disturbances (such as problems with falling and staying asleep), and symptoms of sleep-disordered breathing (SDB, such as snoring and sleep apneas) were measured by questionnaires.

RESULTS

Among the participants, 4,941 subjects (25.1%) fulfilled the criteria for MetS. In the entire sample, both short and long sleep durations were associated with higher prevalence of MetS as compared to normal sleep duration. When stratified by age, a similar pattern was observed for middle-aged subjects (<65 years old; prevalence ratio (PR) [95% CI], 1.13 [1.06-1.22] for short sleep and 1.26 [1.06-1.50] for long sleep duration). In contrast, in older individuals (≥65 years old), only long sleep duration was linked to a higher prevalence of MetS (1.26 [1.12-1.42]; P < 0.01 for sleep duration × age). In the entire cohort, having at least one SDB symptom ≥4 times per week was linked to an increased prevalence of MetS; however, the PR was higher in middle-aged subjects compared with older subjects (1.50 [1.38-1.63] vs. 1.36 [1.26-1.47], respectively; P < 0.001 for SDB × age). Finally, independent of subjects' age, reports of sleep disturbances (i.e., at least one symptom ≥4 times per week) were associated with a higher likelihood of having MetS (1.12 [1.06-1.18]; P > 0.05 for sleep disturbance × age).

CONCLUSION

Our results suggest that age may modify the associations between some sleep parameters and the prevalence of MetS.

Severe insomnia is associated with hypertriglyceridemia in women with major depression treated in psychiatry settings

BACKGROUND

Hypertriglyceridemia (HTG) is a cardiovascular risk factor. In the general population, elevated fasting triglyceridemia (TG) is associated with insomnia. Since insomnia is a core symptom of Major Depressive Episodes (MDE), we studied the association of severe insomnia with HTG in major depression.

METHODS

We used the baseline data of the METADAP cohort, comprising 624 patients with a current MDE in a context of Major Depressive Disorder treated in psychiatry settings, without current alcohol use disorders. Patients were screened for severe insomnia, defined by a score of four or more on the three Hamilton Depression Rating Scale (HDRS) sleep items, and for HTG characterised by TG≥200mg/dL.

RESULTS

Severe insomnia was observed in 335(54%) patients with a current MDE, of whom 234(70%) were women; 49(8%) patients had HTG, of whom 25(51%) were women. 69(11%) patients were treated with lipid-lowering drugs. Severe insomnia was associated with a higher frequency of HTG in the whole sample (9.9% vs 5.6%, p=0.046) and in the subgroup of women (9.0% vs 2.0%, p=0.002). Multivariate logistic regression analyses adjusted for age, education levels, BMI and total HDRS scores confirmed the association between severe insomnia and HTG in the whole sample (OR=2.02, 95%CI [1.00-4.08], p=0.05) as well as in the subgroup of women (OR=4.82, 95%CI [1.5-15.5], p=0.008). No association was shown in men.

PERSPECTIVES

HTG should be systematically investigated in depressed patients with severe insomnia and particularly in women. Further studies are needed to explain the association we observed between severe insomnia and HTG.

Obstructive sleep apnea predicts risk of metabolic syndrome independently of obesity: a meta-analysis

INTRODUCTION

Obstructive sleep apnea (OSA) has been suggested to be associated with a high risk of metabolic syndrome (MS). However, results on whether the association between OSA and risk of MS is independent of obesity, and the effect of nocturnal intermittent hypoxia (IH) on MS, are conflicting. Our purpose was to estimate the magnitude of the independent association between OSA and risk of MS and further explore whether nocturnal IH in OSA plays a role in MS risk.

MATERIAL AND METHODS

The PubMed and EMBASE databases were systematically searched (until January 21, 2015) for available observational evidence. Unadjusted and body mass index (BMI)-adjusted pooled odds ratios (ORs) for MS in OSA or higher nocturnal IH were calculated using fixed or random models. Tests of homogeneity, publication bias, and robustness of the results were performed.

RESULTS

A total of 13 independent studies (involving 857 participants in 3 case-control studies and 7077 participants in 10 cross-sectional studies) were included. The OSA was significantly associated with an increased risk of MS in a meta-analysis of 10 studies (pooled OR = 1.72, 95% CI: 1.31-2.26, p < 0.001), with a BMI-adjusted pooled OR of 1.97 (95% CI: 1.34-2.88, p < 0.001). Pooled results from 3 studies on the oxygen desaturation index (ODI) and MS risk (OR = 1.96, 95% CI: 1.73-2.22, p < 0.001) and 3 studies on the cumulative percentage of sleep time with SpO₂ below 90% (CT90) and MS risk (OR = 1.05, 95% CI: 1.02-1.07, p < 0.001) were also significant.

CONCLUSIONS

Our findings demonstrated a significant association between OSA and increased MS risk independent of BMI, and further indicated a role of nocturnal IH in this association.

The association between obstructive sleep apnea and metabolic syndrome: a systematic review and meta-analysis

Background

Obstructive sleep apnea (OSA) is characterized by repeated episodes of obstruction of the upper airway. Numerous studies have indicated a relationship between OSA and metabolic syndrome (MS), but the results remain debatable. We aimed to perform a systematic review and meta-analysis to evaluate the association between OSA and MS.

Methods

We searched electronic databases (PubMed, EMBASE, and ISO Web of Knowledge) up to September 2014 with English-language restriction. Cross-sectional, case–control, and cohort studies in which the presence of OSA was assessed by objective measurements, the exposure of interest was OSA, and the outcome of interest was the presence (or incidence) of MS were included. The adjusted odds ratios (ORs) (or relative risk) and 95 % confidence intervals (CIs) were extracted and pooled. Sensitivity analyses were conducted, and heterogeneity and publication bias were assessed.

Results

Overall, 15 cross-sectional (2456 patients with OSA and 1705 subjects without OSA), five case–control (1156 OSA patients and 404 controls), and no cohort studies were included. The pooled ORs of MS in individuals with OSA for cross-sectional and case–control studies were 2.87 (95 % CI: 2.41–3.42) and 2.56 (95 % CI: 1.98–3.31), respectively. There was clinically unimportant (I² = 20 %) and moderate (I² = 35 %) between-study heterogeneity of the analysis. The pooled crude ORs of MS in individuals with mild and moderate-to-severe OSA was 2.39 (95 % CI: 1.65–3.46) and 3.45 (95 % CI: 2.33–5.12), respectively, and there was substantial heterogeneity in the meta-analyses (I² = 53 % and I² = 63 %, respectively). However, no evidence of publication bias was detected.

Conclusions

OSA is shown to be associated with MS, although causality between these two factors has not been demonstrated yet. Future cohort and randomized controlled studies are needed.

Electronic supplementary material

The online version of this article (doi:10.1186/s12890-015-0102-3) contains supplementary material, which is available to authorized users.

Insomnia and sleep apnea in midlife women: prevalence and consequences to health and functioning

Sleep disturbance is common during the menopausal transition, with numerous downstream consequences to health and functioning, including reduced quality of life, impaired mental health, and increased physical health morbidity. Insomnia affects approximately 50% of midlife women and is characterized by nocturnal symptoms of difficulties initiating or maintaining sleep (or both) and daytime symptoms that impair occupational, social, or other components of functioning. In addition, approximately 20% of midlife women develop sleep-disordered breathing during the menopausal transition. This commentary summarizes the prevalence, risk factors, and treatment options for each of these sleep disorders in midlife women, with specific focus on first-line treatments for insomnia (cognitive behavioral therapy for insomnia) and sleep-disordered breathing (continuous positive airway pressure) and unique considerations for treating sleep disorders in midlife women. Future directions are also discussed.

Sleep-disordered breathing during pregnancy: future implications for cardiovascular health

IMPORTANCE

Cardiovascular disease (CVD) is a common condition in postreproductive females. Key risk factors for later-life CVD include gestational hypertension (GHTN) and preeclampsia (PE). Although several risk factors of hypertension in pregnancy are well recognized, a novel risk factor that has emerged recently is sleep-disordered breathing (SDB), a condition characterized by repeated closure of the upper airway during sleep with disrupted ventilation and sleep fragmentation. In the nonpregnant population, SDB is now known to play a causal role in future CVD.

OBJECTIVE

The aim of this study was to propose the hypothesis that occult SDB during pregnancy may play a role in long-term CVD in women who had hypertensive disorders of pregnancy.

EVIDENCE ACQUISITION

This study is a review and synthesis of empirical evidence that links SDB to GHTN/PE and GHTN/PE to future CVD.

RESULTS

An increasing body of evidence supports the relationship between SDB and hypertensive disorders of pregnancy via mechanisms of inflammation, oxidative stress, and endothelial dysfunction. It is well established that hypertensive disorders of pregnancy are associated with long-term risk for CVD via similar mechanisms. However, no studies have addressed the potential role of SDB in long-term outcomes of women with GHTN/PE during pregnancy.

CONCLUSIONS

Given the suggested mechanisms that explain these associations, it is plausible that SDB during pregnancy may increase long-term cardiovascular morbidity and mortality.

RELEVANCE

Pregnancy may offer a window of opportunity for identification and treatment of SDB, which could provide substantial health benefit for many years to come.

Sleep hygiene behaviors among midlife women with insomnia or sleep-disordered breathing: the SWAN sleep study

BACKGROUND

Insomnia and sleep-disordered breathing (SDB) are the most common sleep disorders among midlife women. Although promoting sleep hygiene behaviors may be a useful behavioral approach for the management of insomnia or SDB, the frequency with which women engage in these behaviors is unclear.

METHODS

Participants were from the Study of Women's Health Across the Nation (SWAN) Sleep Study (N=321; age range=48-58 years). Out of the full sample, 10.3% (n=33) met Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition diagnostic criteria for insomnia, 15.3% (n=49) had clinically significant SDB (apnea-hypopnea index ≥15), and 4.7% (n=15) met criteria for both insomnia and SDB, resulting in an overall prevalence of 15.0% (n=48) for insomnia and 19.9% (n=64) for SDB. Participants provided diary-based assessments of sleep hygiene behaviors for 14-35 days. Two positive behaviors (sufficient exercise, regular morning out-of-bed time) and four negative behaviors (taking long daytime naps, caffeine consumption near bedtime, alcohol consumption near bedtime, smoking) were examined. These behaviors were compared between women with and without insomnia or SDB following adjustment for sociodemographic factors and mental and physical health indices.

RESULTS

Women with insomnia engaged in significantly fewer negative sleep hygiene behaviors than women without insomnia (1.61±0.15 vs. 2.09±0.09 behaviors; p<0.01); specifically, women with insomnia were less likely to take long naps (odds ratio [OR]=0.30, 95% confidence interval [CI]: 0.12-0.74) or consume caffeine near bedtime (OR=0.44, 95% CI: 0.20-0.98). In contrast, women with SDB were less likely to be physically active than women without SDB (OR=0.52, 95% CI: 0.27-0.98), but no other differences in sleep hygiene behaviors were observed.

CONCLUSIONS

These data suggest that insomnia in midlife women is not associated with poor sleep hygiene. Increasing physical activity may be a valuable recommendation for midlife women with SDB.

Treating obstructive sleep apnea with continuous positive airway pressure benefits type 2 diabetes management

Type 2 diabetes mellitus (T2DM) and obstructive sleep apnea (OSA) are both common major public health concerns. Epidemiological and clinical evidence postulates that OSA may be a causal factor in the pathogenesis of T2DM. This review examines recent empirical developments in theory, research, and practice regarding T2DM and OSA. We first examined the data from 10 studies that covered 281 patients with T2DM who used continuous positive airway pressure therapy, followed by research that describes how hypoxia/reoxygenation in OSA may be key triggers that initiate or contribute to the status of insulin resistance and inflammation. We then propose mechanisms that may relate diabetes with OSA. The issues that should be addressed in the future are outlined. We suggest that intervention with continuous positive airway pressure may improve diabetic symptoms and should be encouraged for patients with diabetes.

Snoring, daytime sleepiness, and incident cardiovascular disease in the health, aging, and body composition study

OBJECTIVES

To examine the association between snoring and incident cardiovascular disease (CVD).

DESIGN SETTINGS AND PARTICIPANTS

This is a prospective study in which community dwelling older adults were evaluated at baseline, and followed up for an average of 9.9 years.

MEASUREMENTS

Data on snoring, daytime sleepiness, as well as demographic and clinical characteristics of study participants was collected at baseline, and participants were followed up every six months for an average of 9.9 years. Based on snoring and sleepiness status, 4 groups of participants were created: (1) No Snoring, No Sleepiness; (2) No Snoring, Sleepiness; (3) Snoring, No Sleepiness; (4) Snoring, Sleepiness. Incident CVD was defined as a diagnosis of myocardial infarction, angina pectoris, or congestive heart failure that resulted in overnight hospitalization during the follow-up period. Cox proportional hazard was used to estimate the risk of incident cardiovascular disease during follow-up by baseline snoring and sleepiness status.

RESULTS

A total of 2,320 participants with a mean age of 73.6 (2.9) years at baseline were included in the analysis. Fifty-two percent were women, and 58% were white. A total of 543 participants developed CVD events during the follow-up period. Participants who reported snoring associated with daytime sleepiness had significantly increased hazard ratio for CVD events (HR = 1.46 [1.03-2.08], P = 0.035) after adjusting for demographic and clinical confounding factors.

CONCLUSION

The results suggest that self-reported snoring and daytime sleepiness status are associated with an increased risk of future cardiovascular disease among older adults.

Physical activity and sedentary time in persons with obstructive sleep apnea and overweight enrolled in a randomized controlled trial for enhanced physical activity and healthy eating

BACKGROUND

The aim of the study was to describe the amount of physical activity and sedentary time in patients with obstructive sleep apnea syndrome (OSAS) and overweight and to explore potential disease-related and psychological correlates.

METHODS

A descriptive and correlational study was performed. Prospective data of physical activity and sedentary time were collected through accelerometry, and body mass index (BMI), daytime sleepiness, exercise self-efficacy, fear of movement, and depressive symptoms were measured at one point. Seventy-three participants with overweight (mean BMI, 35 kg/m(2) (5 SD)) and moderate/severe OSAS (apnea-hypopnea index ≥15) were consecutively recruited. Multivariate associations were determined through multiple linear regression analysis.

RESULTS

The participants took a daily average of 7,734 (3,528 SD) steps, spent an average of 77 min (54 SD) in moderate-to-vigorous physical activity (MVPA), and spent 11 h and 45 min (2 h and 8 min SD) sedentary. BMI, daytime sleepiness, exercise self-efficacy, fear of movement, and depressive symptoms did not explain variance in MVPA or steps but explained 22.9 % of variance in sedentary time. In backward selection analysis, BMI contributed to the explanatory degree of MVPA with 9 % whereas, fear of movement explained 6.3 % of the variance in steps and 14.3 % of the variance in sedentary time.

CONCLUSIONS

An important implication for future physical activity interventions is that both physical activity and sedentary behaviors should be targeted, and fear of movement may be an important determinant for change in patients with OSAS and overweight.

Pathobiology of obstructive sleep apnea-related dyslipidemia: focus on the liver

Obstructive sleep apnea and dyslipidemia are common medical disorders that independently increase vascular morbidity and mortality. Current animal and human data show that, indeed, obstructive sleep apnea may mediate pathological alterations in cholesterol and triglyceride metabolism. The mechanisms involved are increased lipolysis, decreased lipoprotein clearance, and enhanced lipid output from the liver. Human evidence shows that the treatment of obstructive sleep apnea with continuous positive airway pressure leads to an improvement of postprandial hyperlipidemia. However, more studies are needed, to clarify the pathophysiology of the interrelationship between obstructive sleep apnea and dyslipidemia and whether treatment of obstructive sleep apnea will lead to an improvement in the lipid profile and, more importantly, reduce hyperlipidemia-related vascular outcomes.

Level of agreement between methods for measuring moderate to vigorous physical activity and sedentary time in people with obstructive sleep apnea and obesity

BACKGROUND

There is ambiguity about what measures to use to best identify physical activity and sedentary behavior, and agreement between methods for measuring physical activity and sedentary behavior in people with obstructive sleep apnea syndrome (OSAS) and obesity has not been evaluated.

OBJECTIVE

The objective of this study was to examine the level of agreement between an accelerometer and a self-report questionnaire (International Physical Activity Questionnaire [IPAQ]) or a logbook for measuring time spent on moderate to vigorous physical activity and time spent sedentary in people with OSAS and obesity.

DESIGN

This prospective study was a psychometric evaluation of agreement between measurement methods.

METHODS

Thirty-nine people who were obese (body mass index: X=36.1 kg/m², SD=4.35) and had moderate to severe OSAS (apnea-hypopnea index of ≥15) were consecutively recruited from a sleep clinic in Sweden. All were treated with continuous positive airway pressure and were waiting for a follow-up sleep evaluation.

RESULTS

Agreement between the measurement methods was limited. For physical activity, the mean difference between the accelerometer and the IPAQ was 47 minutes, and the mean difference between the accelerometer and the logbook was 32 minutes. Agreement was limited for sedentary time as well; the mean difference between the accelerometer and the IPAQ was 114 minutes, and the mean difference between the accelerometer and the logbook was 86 minutes.

LIMITATIONS

The small sample size may affect the interpretation and generalizability of the results.

CONCLUSIONS

The results imply that the methods cannot be used interchangeably. A combination of an accelerometer and a daily logbook seems to provide a detailed description of physical activity and sedentary behavior.

Obstructive sleep apnea and pregnancy: the effect on perinatal outcomes

Obstructive sleep apnea (OSA) is characterized by repeated episodes of upper airway obstruction, resulting in hypoxemia, hypercapnia and sleep fragmentation. Pathophysiological sequelae include sympathetic activation, increased oxidative stress and a generalized inflammatory response, culminating in endothelial dysfunction. These are the proposed mechanisms that mediate the increased risk of hypertension and cardiovascular disease among patients with OSA outside of pregnancy. It is intriguing to consider the consequences of these events on pregnancy outcomes. There is a growing literature on the impact of maternal OSA on hypertensive disorders of pregnancy, gestational diabetes and impaired fetal growth. The data, while promising, require confirmation with larger numbers to verify the findings. OSA may be an important mediator of the poor perinatal outcomes associated with maternal obesity; moreover, one which may be amenable to treatment. This review discusses OSA and summarizes the current literature linking OSA with adverse perinatal outcomes.