Chronic sleep complaints in premenopausal women and their association with sleep-disordered breathing

Cardiovascular and somatic comorbidities and sleep measures using three hypopnea criteria in mild obstructive sleep-disordered breathing: sex, age, and body mass index differences in a retrospective sleep clinic cohort

STUDY OBJECTIVES

To describe sex, age, and body mass index (BMI) differences in comorbidities and polysomnography measures, categorized using 3 different apnea-hypopnea index (AHI) criteria in sleep clinic patients with mild obstructive sleep-disordered breathing.

METHODS

A retrospective cohort of 305 (64% female) adult sleep clinic patients who underwent full-night in-laboratory polysomnography having been diagnosed with mild sleep-disordered breathing and prescribed positive airway pressure. Effects of sex, age, and BMI on comorbidities and polysomnography measures, including rates of AHI defined by ≥ 3% desaturations (AHI_3%), with arousals (AHI_3%A), by ≥ 4% desaturations (AHI_4%), and by respiratory disturbance index, were evaluated.

RESULTS

Sixty-nine (23%), 116 (38%), 258 (85%), and 267 (88%) patients had AHI_4%, AHI_3%, AHI_3%A, and respiratory disturbance index ≥ 5 events/h, respectively. Ninety-day positive airway pressure adherence rates were 45.9% overall and higher in women > 50-years-old (51.2%, P = 0.013) and men (54.5%, P = 0.024) with no difference whether AHI_4% or AHI_3%A was < 5 or ≥ 5 events/h. Men and women had similar rates of daytime sleepiness (43.3%), anxiety (44.9%), and hypertension (44.9%). Women were more likely to have obesity, anemia, asthma, depression, diabetes, fibromyalgia, hypothyroidism, migraine, and lower rates of coronary artery disease. More patients with AHI_4% < 5 events/h had depression, migraines, and anemia, and more patients with AHI_4% ≥ 5 events/h had congestive heart failure. Women were more likely to have higher sleep maintenance and efficiency, shorter average obstructive apnea and hypopnea durations, and less supine-dominant pattern. Average obstructive apnea and hypopnea duration decreased with increasing BMI, and average hypopnea duration increased with age. Obstructive apnea duration and obstructive hypopnea with arousal duration decreased with increasing BMI. More women had AHI_4% < 5 (81.5% vs 69.1%), AHI_3% < 5 (68.7% vs 49.1%), and AHI_3%A < 5 events/h (18.5% vs 10.0%). Greater age and higher BMI were associated with higher AHI.

CONCLUSIONS

Current AHI criteria do not predict comorbidities or adherence in mild sleep-disordered breathing patients. In this hypothesis-generating descriptive analysis, sex, BMI, and age may all be factors that should be accounted for in future research of mild sleep-disordered breathing patients. Different sleep study measures may weigh differently in calculations of risk for cardiovascular versus somatic comorbidities.

Prediction Models of Obstructive Sleep Apnea in Pregnancy: A Systematic Review and Meta-Analysis of Model Performance

BACKGROUND

Gestational obstructive sleep apnea (OSA) is associated with adverse maternal and fetal outcomes. Timely diagnosis and treatment are crucial to improve pregnancy outcomes. Conventional OSA screening questionnaires are less accurate, and various prediction models have been studied specifically during pregnancy.

METHODS

A systematic review and meta-analysis were performed for multivariable prediction models of both development and validation involving diagnosis of OSA during pregnancy.

RESULTS

Of 1262 articles, only 6 studies (3713 participants) met the inclusion criteria and were included for review. All studies showed high risk of bias for the construct of models. The pooled C-statistics (95%CI) for development prediction models was 0.817 (0.783, 0850), I² = 97.81 and 0.855 (0.822, 0.887), I² = 98.06 for the first and second-third trimesters, respectively. Only multivariable apnea prediction (MVAP), and Facco models were externally validated with pooled C-statistics (95%CI) of 0.743 (0.688, 0.798), I² = 95.84, and 0.791 (0.767, 0.815), I² = 77.34, respectively. The most common predictors in the models were body mass index, age, and snoring, none included hypersomnolence.

CONCLUSIONS

Prediction models for gestational OSA showed good performance during early and late trimesters. A high level of heterogeneity and few external validations were found indicating limitation for generalizability and the need for further studies.

Flow limitation/obstruction with recovery breath (FLOW) event for improved scoring of mild obstructive sleep apnea without electroencephalography

OBJECTIVE

Apnea/hypopnea index (AHI), especially without arousal criteria, does not adequately risk stratify patients with mild obstructive sleep apnea (OSA). We describe and test scoring reliability of an event, Flow Limitation/Obstruction With recovery breath (FLOW), representing obstructive airflow disruptions using only pressure transducer and snore signals available without electroencephalography.

METHODS

The following process was used (i) Development of FLOW event definition, (ii) Training period and definition refinement, and (iii) Reliability testing on 10 100-epoch polysomnography (PSG) samples and two 100-sample tests. Twenty full-night in-laboratory baseline PSGs in OSA patients with AHI with ≥4% desaturations <15 were rescored for FLOW events, traditional hypopneas with desaturations, respiratory-related arousal (RRA) events (hypopneas with arousals and respiratory-effort related arousals) and non-respiratory arousals (NRA).

RESULTS

Scoring of FLOW events in 100-epoch samples had good reliability with intraclass correlation (ICC) of 0.91. The overall kappa for presence of events on two sets of 100 sample events was 0.84 and 0.87 demonstrating good agreement. Moreover, 80% of RRA and 8% of NRA were concurrent with FLOW events. Furthermore, 56% of FLOW events were independent of RRA events. FLOW stratifies patients in traditional AHI categories with 50%/8% of AHI with ≥3% desaturations (AHI3) <5 and 12%/63% of AHI3 >5 in lowest/highest tertiles of AHI3 plus FLOW index.

CONCLUSIONS

Scoring of FLOW after training is reliable. FLOW scores a high proportion of RRA and many currently unrepresented obstructive airflow disruptions. FLOW allows for stratification within the current normal-mild OSA category, which may better identify patients who will benefit from treatment.

Clinical observation of a patient with arterial hypertension and obstructive sleep apnea syndrome

The clinical observation of a postmenopausal patient with the syndrome of obstructive sleep apnea in the outpatient health care stage.

Sleep-disordered breathing and the menopausal transition among participants in the Sleep in Midlife Women Study

OBJECTIVE

Menopause is widely believed to be an established cause of sleep disorders, but evidence for this theory is inconclusive. Attributing any sleep problem to normal processes of menopause may lead to underdiagnosis of treatable sleep disorders in midlife women. This study uses detailed longitudinal data on sleep and menopausal health from participants in the Sleep in Midlife Women Study to investigate whether risk and severity of sleep-disordered breathing increase with progression through menopause, accounting for changes in age and body habitus.

METHODS

A total of 219 women aged 38 to 62 years were recruited from participants in the Wisconsin Sleep Cohort Study. Menopause status was determined from daily diaries in which participants reported menstrual flow, hot flashes, and use of hormonal medications. Each participant underwent in-home polysomnography studies every 6 months, to measure the apnea-hypopnea index (AHI) (N = 1,667 studies). Linear models with empirical standard errors were fit for logarithm of AHI on menopause status and years in menopause, adjusting for age, body mass index, waist girth, and neck girth.

RESULTS

Compared with women in premenopause, AHI was 21% higher among participants in perimenopause (95% CI, -4 to 54), 31% higher among participants in postmenopause (95% CI, 2-68), and 41% higher among participants whose menopausal stage could not be distinguished between peri- and postmenopause (95% CI, 8-82). Among women who had begun perimenopause, each additional year in menopause was associated with 4% greater AHI (95% CI, 2-6).

CONCLUSIONS

Progression through menopause is associated with greater sleep-disordered breathing severity. This association is independent of aging and changes in body habitus.

Performance of screening questionnaires for obstructive sleep apnea during pregnancy: A systematic review and meta-analysis

This review aims to evaluate the performance of obstructive sleep apnea (OSA) screening questionnaires during pregnancy. A systematic review and meta-analysis was performed using MEDLINE Scopus, CINAHL, and the Cochrane library. A bivariate meta-analysis was applied for pooling of diagnostic parameters. Six of the total 4719 articles met the inclusion criteria. The Berlin questionnaire (BQ, N = 604) and Epworth sleepiness scale (ESS, N = 420) were the most frequently used screening tools during pregnancy. The pooled prevalence of OSA during pregnancy was 26.7% (95%CI: 16.9%, 34.4%, I² = 83.15%). BQ performance was poor to fair with pooled sensitivity and specificity of 0.66 (95%CI: 0.45, 0.83; I² = 78.65%) and 0.62 (95%CI: 0.48, 0.75; I² = 81.55%), respectively. BQ performance was heterogeneous depending on type of reference test and pregnancy. Sensitivity increased if diagnosis was based on polysomnography (0.90), and respiratory disturbance index (0.90). However, sensitivity decreased if screening was performed in early pregnancy (≤20 weeks gestation: 0.47), and high-risk pregnancy (0.44). Performance of ESS was poor with pooled sensitivity and specificity of 0.44 (95%CI: 0.33, 0.56; I² = 32.8%) and 0.62 (95%CI: 0.48, 0.75; I² = 81.55%), respectively. In conclusion, BQ and ESS showed poor performance during pregnancy, hence a new OSA screening questionnaire is needed. Registration: PROSPERO registration CRD42015025848.

The role of flow limitation as an important diagnostic tool and clinical finding in mild sleep-disordered breathing

Obstructive sleep apnea (OSA) is defined by quantifying apneas and hypopneas along with symptoms suggesting sleep disruption. Subtler forms of sleep-disordered breathing can be missed when this criteria is used. Newer technologies allow for non-invasive detection of flow limitation, however consensus classification is needed. Subjects with flow limitation demonstrate electroencephalogram changes and clinical symptoms indicating sleep fragmentation. Flow limitation may be increased in special populations and treatment with nasal continuous positive airway pressure (CPAP) has been shown to improve outcomes. Titrating CPAP to eliminate flow limitation may be associated with improved clinical outcomes compared to treating apneas and hypopneas.

Airflow limitations in pregnant women suspected of sleep-disordered breathing

BACKGROUND AND AIM

Pregnancy physiology may predispose women to the development of airflow limitations during sleep. The goal of this study was to evaluate whether pregnant women suspected of sleep-disordered breathing (SDB) are more likely to have airflow limitations compared to non-pregnant controls.

METHODS

We recruited pregnant women referred for polysomnography for a diagnosis of SDB. Non-pregnant female controls matched for age, body mass index (BMI), and apnoea-hypopnoea index (AHI) were identified from a database. We examined airflow tracings for changes in amplitude and shape. We classified airflow limitation by (a) amplitude criteria defined as decreased airflow of > or =10 s without desaturation or arousal (FL 10), or decreased airflow of any duration combined with either 1-2% desaturation or arousal, (FL 1-2%); and (b) shape criteria defined as the presence of flattening or oscillations of the inspiratory flow curve.

RESULTS

We identified 25 case-control pairs. Mean BMI was 44.0±6.9 in cases and 44.1±7.3 in controls. Using shape criteria, pregnant women had significantly more flow-limited breaths throughout total sleep time (32.4±35.8 vs. 9.4±17.9, p<0.0001) and in each stage of sleep (p<0.0001) than non-pregnant controls. In a subgroup analysis, pregnant women without a diagnosis of obstructive sleep apnoea (OSA) who had an AHI <5 had similar findings (p<0.0001). There was no difference in airflow limitation by amplitude criteria between pregnant women and controls (p=0.22).

CONCLUSIONS

Pregnant women suspected of OSA have more frequent shape-defined airflow limitations than non-pregnant controls, even when they do not meet polysomnographic OSA criteria.

Accurate scoring of the apnea-hypopnea index using a simple non-contact breathing sensor

Sleep apnea is a serious condition that afflicts many individuals and is associated with serious health complications. Polysomnography, the gold standard for assessing and diagnosing sleep apnea, uses breathing sensors that are intrusive and can disrupt the patient's sleep during the overnight testing. We investigated the use of breathing signals derived from non-contact force sensors (i.e. load cells) placed under the supports of the bed as an alternative to traditional polysomnography breathing sensors (e.g. nasal pressure, oral-nasal thermistor, chest belt and abdominal belt). The apnea-hypopnea index estimated using the load cells was not different than that estimated using standard polysomnography leads (t44  = 0.37, P = 0.71). Overnight polysomnography sleep studies scored using load cell breathing signals had an intra-class correlation coefficient of 0.97 for the apnea-hypopnea index and an intra-class correlation coefficient of 0.85 for the respiratory disturbance index when compared with scoring using traditional polysomnography breathing sensors following American Academy of Sleep Medicine guidelines. These results demonstrate the feasibility of using unobtrusive load cells installed under the bed to measure the apnea-hypopnea index.

Improvement in headaches with continuous positive airway pressure for obstructive sleep apnea: a retrospective analysis

OBJECTIVE

We aimed to identify clinical features in patients with severe headaches that predicted obstructive sleep apnea (OSA) and determine clinical and sleep study characteristics that predicted headache improvement with continuous positive airway pressure (CPAP).

BACKGROUND

Many patients with headaches complain of sleep symptoms and have OSA. There is often improvement of headaches with CPAP treatment.

METHODS

We conducted a retrospective chart review of all patients referred to adult neurology clinic for headaches and sent for polysomnography between January 2008 and December 2009. Follow-up ranged from 18 to 42 months.

RESULTS

Eighty-two headache patients (70 females, 12 males) were studied. Mean age was 45±13 years (females 45±13, males 43±11) and mean body mass index was 32±9. Headache types included 17% chronic migraine without aura, 22% episodic migraine without aura, 32% migraine with aura, 21% tension-type headache, 6% chronic post-traumatic headache, 11% medication overuse headache, and 7% other types. All patients were receiving standard treatment for their headaches by their neurologist. Fifty-two patients (63%) had OSA. Increasing age, female gender, and chronic migraine without aura were predictive of OSA. Of the patients with OSA, 33 (63%) used CPAP and 27 (82%) were adherent to CPAP. Headache improvement was reported by 40 patients (49%) due to either standard medical therapy or CPAP. Patients with OSA who were CPAP adherent (21/27) were more likely to have improvement in headaches than patients intolerant of CPAP (2/6), those that did not try CPAP (8/19), and those who did not have OSA (16/30) (P=.045). Of the 33 patients who used CPAP, 13 reported improvement in headaches specifically due to CPAP therapy and 10 additional patients noted benefit in sleep symptoms. The presence of witnessed apneas (P=.045) and male gender (P=.021) predicted improvement in headaches due to CPAP.

CONCLUSIONS

Headache patients should be evaluated for the presence of OSA. Treating OSA improves headaches in some patients.

Women with partial upper airway obstruction are not less sleepy than those with obstructive sleep apnea

PURPOSE

Sleep-disordered breathing (SDB) differs between genders in terms of the type, signs, and symptoms of the disease. Partial upper airway obstruction is underdiagnosed and undertreated.

METHODS

In this study, we retrospectively investigated respiratory sleep recordings of 601 women, ending up with 240 women for the final statistical analyses. We hypothesized that there are differences between the signs and symptoms of sleep-disordered breathing whether women had partial upper airway obstruction or obstructive sleep apnea.

RESULTS

The results showed no difference in sleepiness between women with partial upper airway obstruction or obstructive sleep apnea. Also, the other main symptoms of SDB were the same between the groups. Micrognathia was more common in women with partial upper airway obstruction than with obstructive sleep apnea.

CONCLUSION

These results indicate that partial upper airway obstruction in women should be clinically recognized like obstructive sleep apnea.

Sleepwalking, a possible side effect of antipsychotic medication

Two case examples and a review of the sleep literature illustrate the potential of antipsychotic medication to trigger sleepwalking episodes in the context of schizophrenia. Causative hypotheses are briefly reviewed, as well as risk factors, differential diagnosis, and management. Sleepwalking may contribute to delusions, aggression, and accidental suicide. It is important to investigate sleep disorders in schizophrenia. They are not rare and may contribute to behavior that increases the stigma and isolation of individuals with schizophrenia.

Clinical assessment of the obstructive sleep apnoea/hypopnoea syndrome

This review focuses on the clinical presentation of the obstructive sleep apnoea/hypopnoea syndrome in adults. Features consistent with the diagnosis are described. A brief discussion of the objective measurement of sleep-disordered breathing, largely in the form of overnight monitoring, is undertaken.