Longitudinal association of sleep-disordered breathing and nondipping of nocturnal blood pressure in the Wisconsin Sleep Cohort Study

The association between depressive symptoms and masked hypertension in participants with normotension measured at research center

Masked hypertension is a risk factor for cardiovascular diseases. However, masked hypertension is sometimes overlooked owing to the requirement for home blood pressure measurements for diagnosing. Mental status influences blood pressure. To reduce undiagnosed masked hypertension, this study assessed the association between depressive symptoms and masked hypertension. This cross-sectional study used data from the Tohoku Medical Megabank Project Community-Based Cohort Study (conducted in Miyagi Prefecture, Japan, from 2013) and included participants with normotension measured at the research center (systolic blood pressure<140 mmHg and diastolic blood pressure <90 mmHg). Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression Scale (Japanese version). Masked hypertension was defined as normotension measured at the research center and home hypertension (home systolic blood pressure ≥135 mmHg or home diastolic blood pressure ≥85 mmHg). The study comprised 6705 participants (mean age: 55.7 ± 13.7 years). Of these participants, 1106 (22.1%) without depressive symptoms and 393 (23.2%) with depressive symptoms were categorized to have masked hypertension. Sex-specific and age-adjusted least mean squares for home blood pressure, not for research blood pressure were significantly higher in the group with depressive symptoms in both sex categories. The multivariate odds ratio for masked hypertension in the patients with depressive symptoms was 1.72 (95% confidence interval: 1.26-2.34) in male participants and 1.30 (95% confidence interval: 1.06-1.59) in female ones. Depressive symptoms were associated with masked hypertension in individuals with normotension measured at the research center. Depressive symptoms may be one of the risk factors for masked hypertension. Depressive symptoms were associated with masked hypertension in individuals with normotension measured at research center.

Recommended assessment and management of sleep disordered breathing in patients with atrial fibrillation, hypertension and heart failure: Taiwan Society of Cardiology/Taiwan Society of sleep Medicine/Taiwan Society of pulmonary and Critical Care Medicine joint consensus statement

Sleep disordered breathing (SDB) is highly prevalent and may be linked to cardiovascular disease in a bidirectional manner. The Taiwan Society of Cardiology, Taiwan Society of Sleep Medicine and Taiwan Society of Pulmonary and Critical Care Medicine established a task force of experts to evaluate the evidence regarding the assessment and management of SDB in patients with atrial fibrillation (AF), hypertension and heart failure with reduced ejection fraction (HFrEF). The GRADE process was used to assess the evidence associated with 15 formulated questions. The task force developed recommendations and determined strength (Strong, Weak) and direction (For, Against) based on the quality of evidence, balance of benefits and harms, patient values and preferences, and resource use. The resulting 11 recommendations are intended to guide clinicians in determining which the specific patient-care strategy should be utilized by clinicians based on the needs of individual patients.

Selecting patients for interventional procedures to treat hypertension

Purpose: Interventional approaches to treat hypertension are an emerging option that may be suitable for patients whose BP control cannot be achieved with lifestyle and/or pharmacotherapy and possibly for those who do not wish to take drug therapy.Materials and Methods: Interventional strategies include renal denervation with radiofrequency, ultrasound and alcohol-mediated platforms as well as baroreflex activation therapy and cardiac neuromodulation therapy. Presently renal denervation is the most advanced of the therapeutic options and is currently being commercialised in the EU.Results: It is apparent that RDN is effective in both unmedicated patients and patients with more severe hypertension including those with resistant hypertension.Conclusion: However, at present there is no evidence for the use of RDN in patients with secondary forms of hypertension and thus evaluation to rule these out is necessary before proceeding with a procedure. Furthermore, there are numerous pitfalls in the diagnosis and management of secondary hypertension which need to be taken into consideration. Finally, prior to performing an intervention it is appropriate to document presence/absence of hypertension-mediated organ damage.

Metabolipidomic Analysis in Patients with Obstructive Sleep Apnea Discloses a Circulating Metabotype of Non-Dipping Blood Pressure

A non-dipping blood pressure (BP) pattern, which is frequently present in patients with obstructive sleep apnea (OSA), confers high cardiovascular risk. The mechanisms connecting these two conditions remain unclear. In the present study we performed a comprehensive analysis of the blood metabolipidome that aims to provide new insights into the molecular link between OSA and the dysregulation of circadian BP rhythmicity. This was an observational prospective longitudinal study involving adults with suspected OSA who were subjected to full polysomnography (PSG). Patients with an apnea-hypopnea index ≥ 5 events/h were included. Fasting plasma samples were obtained the morning after PSG. Based on the dipping ratio (DR; ratio of night/day BP values) measured via 24 h ambulatory BP monitoring, two groups were established: dippers (DR ≤ 0.9) and non-dippers (DR > 0.9). Treatment recommendations for OSA followed the clinical guidelines. Untargeted metabolomic and lipidomic analyses were performed in plasma samples via liquid chromatography-tandem mass spectrometry. Non-dipper patients represented 53.7% of the cohort (88/164 patients). A set of 31 metabolic species and 13 lipidic species were differentially detected between OSA patients who present a physiologic nocturnal BP decrease and those with abnormal BP dipping. Among the 44 differentially abundant plasma compounds, 25 were putatively identified, notably glycerophospholipids, glycolipids, sterols, and fatty acid derivates. Multivariate analysis defined a specific metabotype of non-dipping BP, which showed a significant dose-response relationship with PSG parameters of OSA severity, and with BP dipping changes after 6 months of OSA treatment with continuous positive airway pressure (CPAP). Bioinformatic analyses revealed that the identified metabolipidomic profile was found to be implicated in multiple systemic biological pathways, with potential physiopathologic implications for the circadian control of BP among individuals with OSA.

A Narrative Review of the Association of Obstructive Sleep Apnea with Hypertension: How to Treat Both When They Coexist?

Hypertension (HT) is a worldwide public health issue and an essential risk factor for cardiovascular and cerebrovascular diseases. Obstructive sleep apnea (OSA) is a condition characterized by recurrent episodes of apnea and hypopnea as a consequence of partial or complete obstruction of the upper airways due to anatomic and/or functional disturbances. There is mounting evidence of a relationship between OSA and HT. In patients with OSA, HT is predominantly nocturnal and characterized by high diastolic blood pressure and usually by a nondipping pattern. Optimizing the blood pressure control is recommended in the current guidelines as the first treatment option in hypertensive patients with OSA. Continuous positive airway pressure (CPAP) therapy may reduce blood pressure, albeit only slightly as a stand-alone treatment. CPAP, as an add-on treatment to antihypertensive medication, appears to be an efficient treatment modality when both conditions coexist. This narrative review aims to summarize the current perspectives on the association of OSA with HT and the treatment options available for adults with OSA-related HT.

Respiratory Event-Induced Blood Pressure Oscillations Vary by Sleep Stage in Sleep Apnea Patients

Obstructive sleep apnea (OSA) pathologically stresses the cardiovascular system. Apneic events cause significant oscillatory surges in nocturnal blood pressure (BP). Trajectories of these surges vary widely. This variability challenges the quantification, characterization, and mathematical modeling of BP surge dynamics. We present a method of aggregating trajectories of apnea-induced BP surges using a sample-by-sample averaging of continuously recorded BP. We applied the method to recordings of overnight BP (average total sleep time: 4.77 ± 1.64 h) for 10 OSA patients (mean AHI: 63.5 events/h; range: 18.3-105.4). We studied surges in blood pressure due to obstructive respiratory events separated from other such events by at least 30 s (274 total events). These events increased systolic (SBP) and diastolic (DBP) BP by 19 ± 7.1 mmHg (14.8%) and 11 ± 5.6 mmHg (15.5%), respectively, relative to mean values during wakefulness. Further, aggregated SBP and DBP peaks occurred on average 9 s and 9.5 s after apnea events, respectively. Interestingly, the amplitude of the SBP and DBP peaks varied across sleep stages, with mean peak ranging from 128.8 ± 12.4 to 166.1 ± 15.5 mmHg for SBP and from 63.1 ± 8.2 to 84.2 ± 9.4 mmHg for DBP. The aggregation method provides a high level of granularity in quantifying BP oscillations from OSA events and may be useful in modeling autonomic nervous system responses to OSA-induced stresses.

Efficacy and safety of acupuncture in the treatment of stroke complicated with sleep apnea syndrome: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

stroke patients often have a combination of sleep apnea syndrome, which is an important and modifiable risk factor for stroke prognosis. Acupuncture is one of the measures for sleep apnea syndrome, and it is also widely used in stroke. However, we are concerned that its efficacy and safety in the treatment of stroke with sleep apnea syndrome are not yet clear.

METHODS

This systematic review and meta-analysis was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses schema and was registered with INPLASY (registration number: INPLASY202250113). The following 8 databases were searched: PubMed, Cochrane Library (CENTRAL), Embase, Web of Science, China National Knowledge Infrastructure, Chongqing VIP Information, WanFang Data, and China Biomedical Literature Database limited from the establishment of each database to May 4, 2022. Subject headings, free words, and keywords were used for retrieval. Relevant literature was supplemented by consulting other resources. We assessed the risk of bias in the included studies using the Cochrane risk of bias tool. RevMan 5.4 software (The Cochrane Collaboration, 2020) was used to perform the meta-analysis.

RESULTS

Six records were included, including a total of 513 participants: 256 in the experimental group and 257 in the control group. The results showed that the total effective rate (relative risk = 1.23, 95% confidence interval (CI): 1.13, 1.34, P < .00001), apnea-hypopnea index (mean difference (MD) = -8.39, 95% CI: -9.19, -7.59, P < .00001), Epworth Sleepiness Scale score (MD = -1.59, 95% CI: -2.66, -0.52, P = .004), minimal oxygen saturation (MD = 4.99, 95% CI: 3.5, 6.47, P < .00001), longest duration of apnea (MD = -7.47, 95% CI: -8.97, -5.97, P < .00001), longest duration of apnea (MD = -6.48, 95% CI: -8.60, -4.35, P < .00001), and S100β levels (standard mean difference = -1.52, 95% CI: -1.87, -1.18, P < .00001) were better in the experimental group than in the control group. Simultaneously, the effect of reducing the neuron-specific enolase level in the experimental group was comparable to that in the control group (MD = -3.40, 95% CI: -9.08, 2.29, P = .24).

CONCLUSIONS

Acupuncture can improve the clinical symptoms and related laboratory indicators for sleep apnea syndrome in patients with stroke. More high-quality trials remain urgently needed.

Controversies in Hypertension III: Dipping, Nocturnal Hypertension, and the Morning Surge

A comprehensive approach to hypertension requires out-of-office determinations by home and/or ambulatory monitoring. The 4 phenotypes comparing office and out-of-office pressures in treated and untreated patients include normotension, hypertension, white-coat phenomena, and masked phenomena. Components of out-of-office pressure may be equally as important as mean values. Nighttime pressures are normally 10 - 20% lower than daytime (normal "dipping"). Abnormalities include dipping more than 20% (extreme dippers), less than 10 % (non-dippers), or rising above daytime (risers) and have been associated with elevated cardiovascular risk. Nighttime pressure may be elevated (nocturnal hypertension) in isolation or together with daytime hypertension. Isolated nocturnal hypertension theoretically changes white-coat hypertension to true hypertension and normotension to masked hypertension. Pressure normally peaks in the morning hours ("morning surge") when cardiovascular events are most common. Morning hypertension may result from residual nocturnal hypertension or an exaggerated surge and has been associated with enhanced cardiovascular risk, especially in Asian populations. Randomized trials are needed to determine whether altering therapy based solely on either abnormal dipping, isolated nocturnal hypertension, and/or an abnormal surge is justified.

Non-dipping blood pressure pattern is associated with higher risk of new-onset diabetes in hypertensive patients with obstructive sleep apnea: UROSAH data

OBJECTIVE

Impairment of circadian blood pressure (BP) patterns has been associated with cardiovascular risks and events in individuals with hypertension and in general populations, which are more likely to be found in obstructive sleep apnea (OSA). The aim of this study was to investigate the association of non-dipping BP pattern with new-onset diabetes in hypertensive patients with OSA, based on Urumqi Research on Sleep Apnea and Hypertension (UROSAH) data.

MATERIALS AND METHODS

This retrospective cohort study included 1841 hypertensive patients at least 18 years of age, who were diagnosed with OSA without baseline diabetes and had adequate ambulatory blood pressure monitoring (ABPM) data at enrollment. The exposure of interest for the present study was the circadian BP patterns, including non-dipping and dipping BP pattern, and the study outcome was defined as the time from baseline to new-onset diabetes. The associations between circadian BP patterns and new-onset diabetes were assessed using Cox proportional hazard models.

RESULTS

Among 1841 participants (mean age: 48.8 ± 10.5 years, 69.1% male), during the total follow-up of 12172 person-years with a median follow-up of 6.9 (inter quartile range: 6.0-8.0) years, 217 participants developed new-onset diabetes with an incidence rate of 17.8 per 1000 person-years. The proportion of non-dippers and dippers at enrollment in this cohort was 58.8% and 41.2%, respectively. Non-dippers were associated with higher risk of new-onset diabetes compared with dippers (full adjusted hazard ratio [HR]=1.53, 95% confidence interval [CI]: 1.14-2.06, P=0.005). Multiple subgroup and sensitivity analyses yielded similar results. We further explored the association of systolic and diastolic BP patterns with new-onset diabetes separately, and found that diastolic BP non-dippers were associated with higher risk of new-onset diabetes (full adjusted HR=1.54, 95% CI: 1.12-2.10, P=0.008), whereas for systolic BP non-dippers, the association was nonsignificant after adjusted the confounding covariates (full adjusted HR=1.35, 95% CI: 0.98-1.86, P=0.070).

CONCLUSIONS

Non-dipping BP pattern is associated with an approximately 1.5-fold higher risk of new-onset diabetes in hypertensive patients with OSA, suggesting that non-dipping BP pattern may be an important clinical implication for the early prevention of diabetes in hypertensive patients with OSA.

Predictors for short-term and long-term automatic PAP compliance

STUDY OBJECTIVES

Positive airway pressure (PAP) is considered a standard treatment for obstructive sleep apnea (OSA), but there are compliance issues. As compliance to PAP tends to decrease with time, it is necessary to consider reasons affecting compliance at each period. Therefore, this study aimed to define factors affecting short-term and long-term compliance to PAP therapy.

METHODS

One hundred eighty-seven patients with OSA who started PAP treatment between July 2018 to March 2020 were included. Acceptance and compliance rates were monitored. Demographics, polysomnography (PSG) profiles, cephalometric data, and physical examination results were analyzed to identify factors predictive of PAP compliance at short-term (3 months) and long-term (12 months) periods.

RESULTS

The acceptance rate of PAP was 92.5%. Compliance at 3 months and 12 months was 79.1% and 51.3%, respectively. Higher apnea-hypopnea index (odds ratio [OR] 1.018, P = .049) and older age (OR 1.032, P = .039) were predictive factors of good automatic PAP (APAP) compliance at 3 months. However, long-term compliance was affected by the percentage of duration with O2 desaturation of < 90% (CT90; OR 1.032, P = .011) and baseline self-reported symptom scores such as nasal obstruction (OR 0.819, P = .038) and awakening (OR 0.796, P = .045).

CONCLUSIONS

In PAP use, indicators of OSA severity such as apnea-hypopnea index affect short-term compliance. On the other hand, the mandibular plane to hyoid distance and self-reported symptoms such as nasal obstruction and awakening can affect long-term compliance.

CITATION

Park SI, Kim BK, Lee KE, Hong SD, Jung YG, Kim HY. Predictors for short-term and long-term automatic PAP compliance. J Clin Sleep Med. 2023;19(1):17-26.

Influence of obstructive sleep apnea on postoperative cognitive dysfunction in elderly patients undergoing joint replacement

OBJECTIVE

To clarify the influence of obstructive sleep apnea (OSA) on postoperative cognitive dysfunction (POCD) in elderly patients undergoing joint replacement.

METHODS

This study retrospectively enrolled130 patients who underwent joint replacement in the Department of Orthopaedics of Taizhou Municipal Hospital between January 2019 and March 2021 for analysis. According to polysomnography (PSG) results, 80 patients without OSA were included in group A and 50 with OSA were assigned to group B. The two groups were compared with respect to the following items: surgical indications (length of stay (LOS), intraoperative blood loss (IBL) and operation time (OT), incidence of postoperative delirium (POD), postoperative cognitive function (Mini-mental State Examination, MMSE), neurological function recovery (National Institutes of Health Stroke Scale, NIHSS) and (Scandinavian Stroke Scale, SSS)), mental health (Self-Rating Anxiety Scale (SAS) and Self-Rating Depression Scale (SDS)), compliance, overall response rate (ORR), complications and patient satisfaction.

RESULTS

The LOS and OT were shorter, and the IBL was less in group A compared with those in group B. Group A also showed reduced NIHSS and SSS scores as well as SAS and SDS scores when compared with group B. In addition, lower incidence of POD, and higher compliance, ORR and satisfaction were observed in group A than in group B. In terms of cognitive function, although the MMSE score in both groups decreased after surgery, patients in group B had a lower MMSE score and a milder form of POCD.

CONCLUSIONS

OSA may affect the postoperative cognitive function and adversely influence the treatment outcome of elderly patients undergoing joint replacement.

Long-term Effect of OSA and CPAP Treatment on Blood Pressure in Patients with Acute Coronary Syndrome

RATIONALE

Obstructive sleep apnea (OSA) is prevalent in acute coronary syndrome (ACS) patients and is a cause of secondary hypertension.

OBJECTIVE

To explore the long-term effects of OSA and CPAP treatment on blood pressure (BP) in ACS patients.

METHODS

Post-hoc analysis of the ISAACC study included 1803 patients admitted for ACS (NCT01335087). Patients with OSA (apnea-hypopnea index (AHI) ≥15 events/h) were randomly assigned to receive either CPAP or/and usual care and followed up for one to 5 years. Office BP was determined at each visit.

RESULTS

We included 596 patients without OSA, 978 patients in the usual care/poor CPAP adherence group and 229 patients in the good CPAP adherence group. At baseline, 52% of the patients were diagnosed with hypertension. Median age and body mass index were 59 [52.0;67.0] years and 28.2 [25.6;31.2] kg/m2, respectively. After a median [25th;75th percentile] follow-up of 41.2 [18.3;59.6] months, BP changes were similar between OSA and non-OSA groups. However, we observed an increase in BP in the third tertile of the AHI (AHI>40 events/h) with a maximum difference in mean BP of +3.3 mmHg at 30 months. OSA patients with good CPAP adherence (≥4 hours/night) reduced mean BP after 18 months compared to usual care/poor CPAP adherence patients, maximum mean difference (95% CI) of -4.7 (-6.7,-2.7) mmHg. In patients with severe OSA we observed a maximum mean difference of -7.1 (-10.3,-3.8) mmHg.

CONCLUSIONS

In patients with ACS, severe OSA is associated with a long-term increase in BP, which is reduced by good CPAP adherence.

Obstructive Sleep Apnea and Hypertension: Updates to a Critical Relationship

Purpose of Review

Obstructive sleep apnea (OSA) is an underdiagnosed illness linked to essential hypertension (HTN), resistant hypertension (r-HTN), and cardiovascular disease (CVD). This review provides updates on the epidemiology, pathophysiology, and treatments of OSA-associated HTN.

Recent Findings

Mild sleep apnea increases the risk for HTN. Eighty-nine percent of young patients aged 18–35 with HTN not attributed to secondary causes have underlying OSA. Home sleep studies are noninferior to formal polysomnography for OSA diagnosis. Nocturnal oxygen desaturation rate is positively correlated with HTN severity. Gut microbiome neo-colonization in response to high-fat diet cravings in patients with OSA alters immune function and worsens HTN. Carbonic anhydrase inhibitors and probiotics show newfound potential for OSA-associated HTN treatment. OSA recognition improves hospital outcomes after a STEMI. Hypoxia-inducible factor (HIF) transcription increases in a dose-dependent manner to hypoxia, and HIFs are strongly linked to cancer growth.

Summary

OSA and HTN are comorbid conditions with adversely connected pathophysiology including sympathetic hyperactivity, gut dysbiosis, proinflammation, endothelial damage, rostral fluid shifts, pharyngeal collapse, intravascular fluid retention, nocturnal energy expenditure, and metabolic derangements. The dose–response effect of OSA on HTN severity challenges blood pressure (BP) control, so those with refractory HTN should be screened for OSA.

Nocturnal Blood Pressure Fluctuations in Patients with Rapid Eye Movement-Related Obstructive Sleep Apnea

Rapid eye movement-related obstructive sleep apnea (REM-related OSA) is a polysomnographic phenotype. Nocturnal blood pressure (BP) fluctuations remain unclear in patients with REM-related OSA. We studied 27 patients with REM-related OSA, categorized as having REM-apnea-hypopnea index (REM-AHI) ≥ 5/h, REM-AHI/non-REM-AHI ≥ 2, and non-REM-AHI < 15/h. Beat-to-beat systolic BP (SBP) variability and nocturnal SBP fluctuation patterns using pulse transit time (PTT) were investigated. The maximum increase and average nocturnal SBP were significantly higher in males than in females (p = 0.003 and p = 0.008, respectively). The rate of non-dipping patterns in nocturnal SBP fluctuations was 63% in all patients (males, 70%; females, 50%). Epworth Sleepiness Scale (ESS) and Self-rating Depression Scale (SDS) scores in females were higher than those in males (8.4 ± 6.1 vs. 13.4 ± 5.4 points, p = 0.04; 43.8 ± 7.9 vs. 52 ± 11.6 points, p = 0.04, respectively). A high proportion of patients with REM-related OSA had a non-dipping pattern. Using PPT, we observed that in patients with REM-related OSA, SBP variability was greater in males. Despite clinical symptoms being slightly more severe in females, nocturnal SBP fluctuations should be considered in male patients with REM-related OSA.

Non-dipping nocturnal blood pressure correlates with obstructive sleep apnoea severity in normotensive subjects and may reverse with therapy

Background

Obstructive sleep apnoea (OSA) is strongly associated with systemic hypertension, but there are limited data on the relationship with blood pressure (BP) in normotensive subjects. Here, we examined the relationship of OSA with nocturnal BP in a documented diurnal normotensive cohort, explored potential intermediate pathways and assessed the effects on BP of continuous positive airways pressure (CPAP) therapy.

Methods

65 males referred for assessment of possible OSA and normotensive on 24-hour BP monitoring underwent overnight inpatient polysomnography (age 41±7 years, body mass index (BMI) 34±6 kg·m⁻², apnoea–hypopnoea index (AHI) 14 (interquartile range 5–26)). Urine and serum were assessed for markers of sympathetic activation, renin–angiotensin–aldosterone system activity, oxidative stress, endothelial function and systemic inflammation. In a subset of patients, 24-hour BP monitoring was repeated after CPAP therapy.

Results

Within this normotensive cohort, night-time systolic and diastolic BP and nocturnal BP dip were highest in the fourth OSA severity quartile (p<0.05). Nocturnal BP dip correlated with AHI (r=−0.327, p<0.05) and oxygen desaturation index (ODI) (r=−0.371, p<0.05), but only ODI was an independent predictor of BP dip (B=–0.351, p<0.01) and non-dipping status (B=0.046, p<0.05). Overnight urinary norepinephrine correlated with nocturnal systolic BP (r=0.387, p<0.01) with a trend towards correlation with systolic dipping (p=0.087). In 20 CPAP-treated patients, night-time systolic BP decreased (p<0.05) and mean nocturnal BP dip increased (p≤0.05).

Conclusion

In this normotensive cohort, OSA severity was associated with higher nocturnal BP, which improved following CPAP therapy, and intermittent hypoxia was the most important OSA-related variable in this relationship.

There is a strong association in a normotensive cohort between OSA and nocturnal blood pressure, with intermittent hypoxia as an important mechanistic pathwayhttps://bit.ly/2SFvWiB

Mild obstructive sleep apnea increases hypertension risk, challenging traditional severity classification

STUDY OBJECTIVES

The association of mild obstructive sleep apnea (OSA) with important clinical outcomes remains unclear. We aimed to investigate the association between mild OSA and systemic arterial hypertension (SAH) in the European Sleep Apnea Database cohort.

METHODS

In a multicenter sample of 4,732 participants, we analyzed the risk of mild OSA (subclassified into 2 groups: mild_{AHI 5-<11/h} (apnea-hypopnea index [AHI], 5 to <11 events/h) and mild_{AHI 11-<15/h} (AHI, ≥11 to <15 events/h) compared with nonapneic snorers for prevalent SAH after adjustment for relevant confounding factors including sex, age, smoking, obesity, daytime sleepiness, dyslipidemia, chronic obstructive pulmonary disease, type 2 diabetes, and sleep test methodology (polygraphy or polysomnography).

RESULTS

SAH prevalence was higher in the mild_{AHI 11-<15/h} OSA group compared with the mild_{AHI 5-<11/h} group and nonapneic snorers (52% vs 45% vs 30%; P < .001). Corresponding adjusted odds ratios for SAH were 1.789 (mild_{AHI 11-<15/h}; 95% confidence interval [CI], 1.49-2.15) and 1.558 (mild_{AHI 5-<11/h}; 95%, CI, 1.34-1.82), respectively (P < .001). In sensitivity analysis, mild_{AHI 11-<15/h} OSA remained a significant predictor for SAH both in the polygraphy (odds ratio, 1.779; 95% CI, 1.403-2.256; P < .001) and polysomnography groups (odds ratio, 1.424; 95% CI, 1.047-1.939; P = .025).

CONCLUSIONS

Our data suggest a dose-response relationship between mild OSA and SAH risk, starting from 5 events/h in polygraphy recordings and continuing with a further risk increase in the 11- to <150-events/h range. These findings potentially introduce a challenge to traditional thresholds of OSA severity and may help to stratify participants with OSA according to cardiovascular risk.

Sex differences in the association between arterial hypertension, blood pressure, and sleep apnea in the general population

STUDY OBJECTIVES

To assess sex-related differences in the relationship between hypertension (HT), blood pressure (BP), and sleep apnea in the general population.

METHODS

We performed home polygraphy in a cohort of 1809 men and women in the general population. Office BP was measured. Presence of HT (drug-treated, physician-diagnosed, or high BP during study visit) was also recorded. HT rate and BP were assessed over a range of 7 sleep apnea severity categories based on the respiratory event index (REI).

RESULTS

The age-adjusted HT prevalence rate increased with higher REI in both sexes. After additional adjustment for obesity the association remained significant in women but not in men. In participants not treated with antihypertensive medications, age-adjusted BP increased with REI. Remarkably, the association was already significant within the normal range (REI < 5 events/h). The REI threshold for higher BP was situated at a distinctly lower cutoff point in women compared to men. After additional adjustment for obesity, the associations remained significant for diastolic but not systolic BP.

CONCLUSIONS

Significant increases in the age-adjusted BP and HT rate in the general population were present at lower REI cutoffs in women compared to men. Even a very low number of respiratory events was associated with higher BP and HT prevalence. Adjustment for obesity attenuated these associations, especially in men. Sex differences in BP susceptibility across the sleep apnea spectrum may be present.

Characteristics of hypertension in obstructive sleep apnea: An Asian experience

Obstructive sleep apnea (OSA) is a risk of hypertension and is associated with cardiovascular disease (CVD) incidence. In Asian countries, the prevalence of OSA is high, as in Western countries. When blood pressure (BP) is evaluated in OSA individuals using ambulatory BP monitoring (ABPM), the BP phenotype often indicates abnormal BP variability, such as increased nighttime BP or abnormal diurnal BP variation, that is, non‐dipper pattern, riser pattern, and morning BP surge, and all these conditions have been associated with increased CVD events. Asians have a higher prevalence of increased nighttime BP or morning BP surge than Westerners. Therefore, this review paper focused on OSA and hypertension from an Asian perspective to investigate the importance of the association between OSA and hypertension in the Asian population. Such abnormal BP variability has been shown to be associated with progression of arterial stiffness, and this association could provoke a vicious cycle between abnormal BP phenotypes and arterial stiffness, a phenomenon recognized as systemic hemodynamic atherothrombotic syndrome (SHATS). OSA may be one of the background factors that augment SHATS. An oxygen‐triggered nocturnal oscillometric BP measurement device combined with a pulse oximeter for continuous SpO₂ monitoring could detect BP variability caused by OSA. In addition to treating the OSA, accurate and reliable detection and treatment of any residual BP elevation and BP variability caused by OSA would be necessary to prevent CVD events. However, more detailed detection of BP variability, such as beat‐by‐beat BP monitoring, would further help to reduce CV events.

Effect of Sleep Disturbances on Blood Pressure

This review summarizes recent literature addressing the association of short sleep duration, shift work, and obstructive sleep apnea with hypertension risk, blood pressure (BP) levels, and 24-hour ambulatory BP. Observational studies demonstrate that subjectively assessed short sleep increases hypertension risk, though conflicting results are observed in studies of objectively assessed short sleep. Intervention studies demonstrate that mild and severe sleep restriction are associated with higher BP. Rotating and night shift work are associated with hypertension as shift work may exacerbate the detrimental impact of short sleep on BP. Further, studies demonstrate that shift work may increase nighttime BP and reduce BP control in patients with hypertension. Finally, moderate to severe obstructive sleep apnea is associated with hypertension, particularly resistant hypertension. Obstructive sleep apnea is also associated with abnormal 24-hour ambulatory BP profiles, including higher daytime and nighttime BP, nondipping BP, and a higher morning surge. Continuous positive airway pressure treatment may lower BP and improve BP dipping. In conclusion, efforts should be made to educate patients and health care providers about the importance of identifying and treating sleep disturbances for hypertension prevention and management. Empirically supported sleep health interventions represent a critical next step to advance this research area and establish causality.

Impact of obstructive sleep apnea on left ventricular mass index in men with coronary artery disease

STUDY OBJECTIVES

Left ventricular hypertrophy (LVH) is associated with augmented risk for mortality in patients with coronary artery disease (CAD). These patients often have obstructive sleep apnea (OSA). We aimed to evaluate the relationship between OSA and the left ventricular mass index (LVMI) in men with CAD.

METHODS

Consecutive patients with CAD were recruited and underwent overnight portable monitoring for the assessment of OSA. LVMI was ascertained using high-resolution echocardiography. Univariate and multivariate regression analyses were conducted to explore the associations between the OSA parameters and the LVMI levels.

RESULTS

Of the 1,053 examined male patients with CAD, 425 (40.4%) had moderate-to-severe OSA (respiratory event index ≥ 15 events/h). The prevalence of LVH (LVMI > 125 g/m²) was 36.0% (n = 379). The mean LVMI values increased with increasing OSA severity (P < .001). Patients with respiratory event index ≥ 30 events/h had 2.30 (95% confidence interval 1.50-3.54, P < .001) times increased risk of LVH than those without OSA (respiratory event index < 5 events/h) independent of confounders. The minimum oxygen saturation levels were the strongest factor correlated with LVMI (β = -0.299, P = .004) of several OSA indices. Patients with minimum oxygen saturation < 70% had an adjusted odds ratio of 3.62 (95% confidence interval 1.81-7.25, P < .001) for LVH development compared with those with minimum oxygen saturation ≥ 90%.

CONCLUSIONS

OSA severity was associated with a higher likelihood of LVH in men with CAD, which is partially related to severe nocturnal intermittent hypoxemia. Aggressive effort at managing OSA among patients with CAD may further reduce the cardiovascular risk.

Quantification of Nocturnal Blood Pressure Oscillations Induced by Sleep Disordered Breathing

We present an approach to quantifying nocturnal blood pressure (BP) variations that are elicited by sleep disordered breathing (SDB). A sample-by-sample aggregation of the dynamic BP variations during normal breathing and BP oscillations prompted by apnea episodes is performed. This approach facilitates visualization and analysis of BP oscillations. Preliminary results from analysis of a full night study of 7 SDB subjects (5 Male 2 Female, 52±5.6 yrs., Body Mass Index 36.4±7.4 kg/m², Apnea-Hypopnea Index 69.1±26.8) are presented. Aggregate trajectory and quantitative values for changes in systolic blood pressure (SBP) and diastolic blood pressure (DBP) concomitant with obstructive apnea episodes are presented. The results show 19.4 mmHg (15.3%) surge in SBP and 9.4 mmHg (13.6%) surge in DBP compared to their respective values during normal breathing (p<0.05). Further, the peak of the surge in SBP and DBP occurred about 9s and 7s, respectively, post the end of apnea events. The return of SBP and DBP to baseline values displays a decaying oscillatory pattern.

OSA in patients with head and neck cancer is associated with cancer size and oncologic outcome

Purpose

Obstructive sleep apnea (OSA) is associated with severe daytime sleepiness and reduced quality of life. These symptoms are also present in patients with squamous cell carcinoma of the head and neck (SCCHN) before, during and after treatment, so that comorbidity cannot be excluded. The aim was to evaluate the prevalence of OSA and its impact on the quality of life in patients with oropharyngeal, hypopharyngeal and lateral tongue SCCHN in a prospective study.

Methods

We performed cardiorespiratory home sleep apnea testing and recorded sleep-related patient-reported outcomes in 33 patients with confirmed oropharyngeal, hypopharyngeal and lateral tongue SCCHN. We correlated the sleep-related variables to oncologic variables and endpoints.

Results

Five female and 28 male patients with SCCHN (aged 46–77 years) were recruited. Thirty patients (90%) had OSA as defined by an Apnea/Hypopnea Index (AHI) > 5 /h before treatment. Evaluation after treatment, which was possible in 17 patients, showed OSA in 16 patients (94%). Radiologic primary tumor size showed significant positive correlation with AHI and apnea-index. Tumor recurrence and tumor-related mortality showed significant positive association with AHI. PSQI of these patients showed at least a moderate sleep disturbance. EORTC QLQ c30 questionnaire showed reduced values for all tested qualities, in particular for fatigue, insomnia, pain and financial distress.

Conclusion

Obstructive sleep apnea is a significant comorbidity in patients with SCCHN. Pre-interventional AHI may be correlated with the oncologic outcome. Further research is needed to further describe the course of OSA and its treatment before, during and after therapy.

Sleep-Disordered Breathing and 24-Hour Ambulatory Blood Pressure Monitoring in Renal Transplant Patients: Longitudinal Study

Background Sleep-disordered breathing (SDB) is considered a strong risk factor for hypertension in the general population. This disturbance is common in end-stage kidney disease patients on long-term hemodialysis and improves early on after renal transplantation. Whether SDB may be a risk factor for hypertension in renal transplant patients is unclear. Methods and Results We investigated the long-term evolution of simultaneous polysomnographic and 24-hour ambulatory blood pressure (BP) monitoring recordings in a cohort of 221 renal transplant patients. Overall, 404 paired recordings were made over a median follow-up of 35 months. A longitudinal data analysis was performed by the mixed linear model. The apnea-hypopnea index increased from a median baseline value of 1.8 (interquartile range, 0.6-5.0) to a median final value of 3.6 (interquartile range, 1.7-10.4; P=0.009). Repeated categorical measurements of the apnea-hypopnea index were directly associated with simultaneous 24-hour, daytime, and nighttime systolic ambulatory BP monitoring (adjusted analyses; P ranging from 0.002-0.01). In a sensitivity analysis restricted to 139 patients with at least 2 visits, 24-hour, daytime, and nighttime systolic BP significantly increased across visits (P<0.05) in patients with worsening SDB (n=40), whereas the same BP metrics did not change in patients (n=99) with stable apnea-hypopnea index. Conclusions In renal transplant patients, worsening SDB associates with a parallel increase in average 24-hour, daytime, and nighttime systolic BP. These data are compatible with the hypothesis that the link between SDB and hypertension is causal in nature. Clinical trials are, however, needed to definitively test this hypothesis.

Blood Pressure Increases Before Pulse Rate During the Nocturnal Period in Hypertensive Patients

Ambulatory blood pressure monitoring (ABPM) is used for the evaluation of out-of-office blood pressure (BP), however, knowledge concerning the detailed behavior of nocturnal blood pressure (BP) and pulse rate (PR) is limited.A total of 190 participants (64 ± 15 years, 46.3% males) underwent ABPM for diagnosis of hypertension or evaluation of hypertensive therapy. BP and PR were measured automatically by the oscillometric method. From the hourly average ABPM values, the nocturnal time courses (0 AM to 6 AM) of SBP and PR were determined and compared to each other.In general, SBP fell to the lowest level at around midnight and started to increase progressively towards dawn while PR stayed unchanged until 7 AM. Age and gender affected the time course of SBP, most distinctly in the female patients aged ≥ 60 years. The time course of the increase of SBP was very similar in the patients, with BP dipping and non-dipping. The cardiothoracic ratio (CTR) slightly and renal dysfunction modestly facilitated the increase of nocturnal SBP. The nocturnal increase in SBP was not accompanied by an increase of PR in any group or subgroup. The pathophysiology and clinical significance of the early and exclusive increase in nocturnal BP need to be investigated.Average ABPM values in these hypertensive patients showed that BP starts to increase toward dawn without an increase in PR and that this discrepant behavior between BP and RP was most distinct in females 60 or older. The mechanism and clinical significance of such a discordant variation in BP and PR need to be elucidated.

The relationship between diurnal variation of cytokines and symptom expression in mild obstructive sleep apnea

OBJECTIVES

To identify the relationship between (1) cytokines and everyday symptoms and (2) cytokine diurnal variation and everyday symptoms in mild obstructive sleep apnea (OSA).

METHODS

An observational, single-night study of 20 adults with mild to moderate OSA undergoing diagnostic polysomnography. Everyday symptoms included sleepiness measured by Stanford Sleepiness Scale, fatigue and energy levels measured by Lee Fatigue Scale, and cytokine plasma concentrations including interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor-α (TNF-α) measured concurrent with symptoms at presleep (8 pm to 10 pm; time 1) and postsleep (5 am to 6 am; time. 2) Cytokine diurnal variation was calculated as [time 2 - time 1]. Wilcoxon signed-rank tests and Spearman partial rank correlations adjusted for age, body mass index, cardiovascular disease, and type 2 diabetes were used.

RESULTS

Twenty patients (50% male, obese, median age = 51.0 years) with mild OSA (apnea-hypopnea index, AHI; median 9.5 events/h) were evaluated. Evening IL-6 was associated with evening symptoms, including sleepiness (r = .69, P = .002) and energy level (r = -0.68, P = .003); morning IL-8 (r = .73, P = .001), and TNF-α (r = .59, P = .015) were associated with morning fatigue. Only morning IL-8 (r = -0.57, P = .022) and diurnal variations in IL-8 (r = -0.60, P = .014) were associated with morning energy level.

CONCLUSION

There is scant evidence addressing the diurnal variation of inflammatory biomarkers and the relationship with symptom expression in mild OSA. The present findings provide preliminary mechanistic findings for symptom expression in OSA and contribute insight to mild OSA symptom phenotypes.

Relationship between nocturnal blood pressure patterns and end organ damage and diastolic dysfunction in heart transplant recipients

BACKGROUND

We assessed the relationship between circadian blood pressure (BP) patterns and clinical outcomes in a contemporary cohort of adult heart transplant recipients.

METHODS

This retrospective, cross-sectional study included adult heart transplant recipients at least 6 months post-transplant. Ambulatory BP measurements were recorded over 24 hours. Nondippers were defined as a decline in average nighttime BP ≤ 10% compared with daytime. Primary outcomes were the presence of end organ damage, that is, microalbuminuria, chronic kidney disease, and/or left ventricular hypertrophy. Secondary outcomes were measures of diastolic dysfunction (ie, mitral valve deceleration time, e/e', E/A, and isovolumetric relaxation time), microalbumin/creatinine ratio, eGFR, interventricular septal thickness, and left ventricular posterior wall thickness.

RESULTS

Of 30 patients, 53.3% (n = 16) were systolic nondippers and 40% (n = 12) were diastolic nondippers. Diastolic nondippers had three times higher urine microalbumin/creatinine ratios than diastolic dippers (P = .03). Systolic nondippers had 16.3% lower mitral valve deceleration time (P = .05) than systolic dippers, while diastolic nondippers had 20.4% higher e/e' (P = .05) than diastolic dippers. There were no significant relationships between BP dipping status and any of the primary outcomes.

CONCLUSIONS

These data suggest that systolic and diastolic nondipping BP patterns are associated with subclinical kidney damage and diastolic dysfunction in heart transplant recipients.

Association of Sleep Characteristics With Nocturnal Hypertension and Nondipping Blood Pressure in the CARDIA Study

Background Sleep characteristics and disorders are associated with higher blood pressure (BP) when measured in the clinic setting. Methods and Results We tested whether self-reported sleep characteristics and likelihood of obstructive sleep apnea (OSA) were associated with nocturnal hypertension and nondipping systolic BP (SBP) among participants in the CARDIA (Coronary Artery Risk Development in Young Adults) study who completed 24-hour ambulatory BP monitoring during the year 30 examination. Likelihood of OSA was determined using the STOP-Bang questionnaire. Global sleep quality, habitual sleep duration, sleep efficiency, and midsleep time were obtained from the Pittsburgh Sleep Quality Index. Nocturnal hypertension was defined as mean asleep SBP ≥120 mm Hg or diastolic BP ≥70 mm Hg. Nondipping SBP was defined as a decline in awake-to-asleep SBP <10%. Among 702 participants, the prevalence of nocturnal hypertension and nondipping SBP was 41.3% and 32.5%, respectively. After multivariable adjustment including cardiovascular risk factors, the prevalence ratios (PRs) for nocturnal hypertension and nondipping SBP associated with high versus low likelihood of OSA were 1.32 (95% CI, 1.00-1.75) and 1.31 (95% CI, 1.02-1.68), respectively. The association between likelihood of OSA and nocturnal hypertension was stronger for white participants (PR: 2.09; 95% CI, 1.23-3.48) compared with black participants (PR: 1.11; 95% CI, 0.79-1.56). The PR for nondipping SBP associated with a 1-hour later midsleep time was 0.92 (95% CI, 0.85-0.99). Global sleep quality, habitual sleep duration, and sleep efficiency were not associated with either nocturnal hypertension or nondipping SBP. Conclusions These findings suggest that addressing OSA risk and sleep timing in a clinical trial may improve BP during sleep.

The Importance of Sleep Fragmentation on the Hemodynamic Dipping in Obstructive Sleep Apnea Patients

Introduction

Obstructive sleep apnea (OSA) has been associated with non-dipping blood pressure (BP). The precise mechanism is still under investigation, but repetitive oxygen desaturation and arousal induced sleep fragmentation are considered the main contributors.

Methods

We analyzed beat-to-beat measurements of hemodynamic parameters (HPs) during a 25-min period of wake–sleep transition. Differences in the mean HP values for heart rate (HR), systolic BP (SBP), and stroke volume (SV) during wake and sleep and their standard deviations (SDs) were compared between 34 controls (C) and 22 OSA patients. The Student’s t-test for independent samples and the effect size by Cohen’s d (d) were calculated. HP evolution was investigated by plotting the measured HP values against each consecutive pulse wave. After a simple regression analysis, the calculated coefficient beta (SCB) was used to indicate the HP evolution. We furthermore explored by a hierarchical block regression which variables increased the prediction for the SCB: model 1 BMI and age, model 2 + apnea/hypopnea index (AHI), and model 3 + arousal index (AI).

Results

Between the two groups, the SBP increased in OSA and decreased in C resulting in a significant difference (p = 0.001; d = 0.92). The SV demonstrated a similar development (p = 0.047; d = 0.56). The wake/sleep variation of the HP measured by the SD was higher in the OSA group—HR: p < 0.001; d = 1.2; SBP: p = 0.001; d = 0.94; and SV: p = 0.005; d = 0.82. The hierarchical regression analysis of the SCB demonstrated in SBP that the addition of AI to AHI resulted in ΔR²: +0.163 and ΔF + 13.257 (p = 0.001) and for SV ΔR²: +0.07 and ΔF 4.83 (p = 0.003). The AI but not the AHI remained statistically significant in the regression analysis model 3—SBP: β = 0.717, p = 0.001; SV: β = 0.469, p = 0.033.

Conclusion

In this study, we demonstrated that in OSA, the physiological dipping in SBP and SV decreased, and the variation of all investigated parameters increased. Hierarchical regression analysis indicates that the addition of the AI to BMI, age, and AHI increases the prediction of the HP evolution following sleep onset for both SBP and SV and may be the most important variable.

[Cardiac dysfunction and the obstructive sleep apnoea syndrome]

INTRODUCTION

Cardiac insufficiency affects nearly 2% of the population with increased morbidity/mortality despite advances in therapeutic management. The sleep apnoea syndrome (SAS) is a risk factor for, and cause of aggravation of, myocardial dysfunction.

BACKGROUND

SAS is found in 70% of patients with chronic cardiac failure, 65% of patients with refractory hypertension, 60% of patients with cerebro-vascular accidents and 50% of patients with atrial fibrillation. The associated cardiovascular mortality is multiplied by a factor of 2 to 3. The pathophysiological mechanisms are intermittent nocturnal hypoxia, variations in CO₂ levels, variations in intrathoracic pressure and repeated arrousals from sleep, concurrent with sympathetic hyperactivity, endothelial dysfunction and systemic inflammation.

CONCLUSIONS

SAS and cardiological management in patients presenting with myocardial dysfunction should be combined. It is necessary to pursue the scientific investigations with the aim of determining a precise care pathway and the respective places of each of the cardiological and pulmonary measures.

Obstructive sleep apnea, cognition and Alzheimer's disease: A systematic review integrating three decades of multidisciplinary research

Increasing evidence links cognitive-decline and Alzheimer's disease (AD) to various sleep disorders, including obstructive sleep apnea (OSA). With increasing age, there are substantial differences in OSA's prevalence, associated comorbidities and phenotypic presentation. An important question for sleep and AD researchers is whether OSA's heterogeneity results in varying cognitive-outcomes in older-adults compared to middle-aged adults. In this review, we systematically integrated research examining OSA and cognition, mild cognitive-impairment (MCI) and AD/AD biomarkers; including the effects of continuous positive airway pressure (CPAP) treatment, particularly focusing on characterizing the heterogeneity of OSA and its cognitive-outcomes. Broadly, in middle-aged adults, OSA is often associated with mild impairment in attention, memory and executive function. In older-adults, OSA is not associated with any particular pattern of cognitive-impairment at cross-section; however, OSA is associated with the development of MCI or AD with symptomatic patients who have a higher likelihood of associated disturbed sleep/cognitive-impairment driving these findings. CPAP treatment may be effective in improving cognition in OSA patients with AD. Recent trends demonstrate links between OSA and AD-biomarkers of neurodegeneration across all age-groups. These distinct patterns provide the foundation for envisioning better characterization of OSA and the need for more sensitive/novel sleep-dependent cognitive assessments to assess OSA-related cognitive-impairment.

Sleep apnea and kidney transplant outcomes: findings from a 20-year (1997-2017) historical cohort study

OBJECTIVE/BACKGROUND

A historic cohort single-center study of kidney transplant recipients with graft loss examined the associations between sleep apnea and two transplant outcomes, death with a functioning graft (DWFG), and graft survival time.

PATIENT/METHODS

Adult patients who received transplants and experienced graft failure or DWFG from January 1, 1997 to January 1, 2017 constituted the cohort (n = 322). Data for the study were obtained by merging two secondary data sources: the Organ Procurement and Transplantation Network (OPTN) database and the transplant center's medical records. A Cox regression modeled the association of diagnosed sleep apnea, stratified by year-of transplant surgery, with graft survival time. Using backward elimination, this model was adjusted for recipient age, race/ethnicity, gender, functional status, donor age, and antigen mismatch.

RESULTS

No statistically significant differences were found for proportions of DWFG in those with, versus without, sleep apnea, informing our censoring approach. When examining graft survival time, the Cox regression model was stratified given a sleep apnea and year-of-transplant interaction (p < 0.01, adjusted model). For patients transplanted between 1997 and 2008, sleep apnea was statistically significantly associated with a decreased risk of graft failure or cardiovascular-related DWFG [adjusted Hazard Ratio (aHR) = 0.63, 95%CI, 0.42-0.94]. For patients transplanted between 2009 and 2017, sleep apnea statistically significantly increased the risk of graft failure or cardiovascular-related DWFG (aHR = 2.61, 95%CI, 1.13-6.00).

CONCLUSIONS

In a cohort of transplant recipients with graft loss, sleep apnea increased the risk of graft loss nearly three-fold among patients transplanted between 2009 and 2017. Similar DWFG proportions by sleep apnea presence indicate this risk is likely driven by renal failure, not mortality. Further research on whether treatment of sleep apnea can improve graft survival is warranted.

The Effects of Eplerenone on the Circadian Blood Pressure Pattern and Left Ventricular Hypertrophy in Patients with Obstructive Sleep Apnea and Resistant Hypertension-A Randomized, Controlled Trial

The obstructive sleep apnea (OSA) is highly associated with various significant cardiovascular outcomes such as resistant hypertension (RAH). Despite this, as of now the relationship between high night-time blood pressure (BP) and left ventricular hypertrophy (LVH) in patients with OSA and RAH is not fully understood. The aim of this study was to assess the influence of the addition of eplerenone to a standard antihypertensive therapy on parameters of 24-h ambulatory blood pressure measurement (ABPM) as well as on the results of echocardiography and polysomnography in patients with OSA and RAH. The patients were randomly assigned to one of the two study groups: the treatment group, receiving 50 mg/d eplerenone orally for 6 months (n = 51) and the control group, remaining on their standard antihypertensive therapy (n = 51). After that period, a significant reduction in the night-time BP parameters in the treatment group including an increased night blood pressure fall from 4.6 to 8.9% was noted. Additionally, the number of non-dipper patients was reduced by 45.1%. The treatment group also revealed a decrease in left ventricular hypertrophy and in the apnea-hypopnea index (AHI) with a positive correlation being observed between these two parameters. This study is the first to report the improvement of the circadian BP profile and the improvement of the left ventricle geometry in patients with OSA and RAH following the addition of selective mineralocorticoid receptor antagonists to antihypertensive therapy.

Expert panel consensus recommendations for ambulatory blood pressure monitoring in Asia: The HOPE Asia Network

Hypertension is an important public health issue because of its association with a number of significant diseases and adverse outcomes. However, there are important ethnic differences in the pathogenesis and cardio-/cerebrovascular consequences of hypertension. Given the large populations and rapidly aging demographic in Asian regions, optimal strategies to diagnose and manage hypertension are of high importance. Ambulatory blood pressure monitoring (ABPM) is an important out-of-office blood pressure (BP) measurement tool that should play a central role in hypertension detection and management. The use of ABPM is particularly important in Asia due to the specific features of hypertension in Asian patients, including a high prevalence of masked hypertension, disrupted BP variability with marked morning BP surge, and nocturnal hypertension. This HOPE Asia Network document summarizes region-specific literature on the relationship between ABPM parameters and cardiovascular risk and target organ damage, providing a rationale for consensus-based recommendations on the use of ABPM in Asia. The aim of these recommendations is to guide and improve clinical practice to facilitate optimal BP monitoring with the goal of optimizing patient management and expediting the efficient allocation of treatment and health care resources. This should contribute to the HOPE Asia Network mission of improving the management of hypertension and organ protection toward achieving "zero" cardiovascular events in Asia.

Ambulatory blood pressure monitoring on admission in survivors of recent stroke entering inpatient rehabilitation

Arterial hypertension (AHT) is a major risk factor for stroke, yet blood pressure (BP) goals thereafter remain uncertain. Although additional prognostic value of 24-hour ambulant BP monitoring (ABPM) is acknowledged, its clinical impacts remain limited. We suspected that routine ABPM could identify characteristic circadian BP patterns in different brain lesion types, the knowledge of which might, in turn, be helpful in improving overall BP management in patients after stroke. In our study, we compared cardiovascular parameters derived from ABPM and traditional blood pressure measurements (TBPM) among 105 stroke survivors who entered our inpatient neuro-rehabilitation program. The mean age of mostly male (64.8%) patients was 71 ± 12 years. Ischemic strokes were predominant (75.2%). Despite normotensive systolic BP means in TBPM (133.5 ± 18.2 mmHg) and ABPM (24 h: 122.8 ± 14.7 mmHg), AHT persisted in up to 67.6% of all patients, with ABPM uncovering nocturnal systolic non- or reversed dipping in 89.5% and 53.3%, respectively. The latter was predominant (85.7%) in the hemorrhagic subgroup which also displayed lower daytime SBP than the ischemic one (ABPM: 117.1 ± 11.8 vs 124.7 ± 14.7 mmHg, p = 0.033). Further differences were present among distinct brain lesion types. Sufficient dippers were younger (58 ± 12 vs 75 ± 11 years, p < 0.001), but adjusting for age yielded no independent correlations. In spite of normotensive daytime BP measurements, ABPM detects latent AHT and insufficient nocturnal BP dipping after the acute phase of stroke. Further studies are needed to elucidate the role of increased nocturnal BP in patients after stroke.

Nondipping Nocturnal Blood Pressure Predicts Sleep Apnea in Patients With Hypertension

STUDY OBJECTIVES

Systemic hypertension is highly prevalent in obstructive sleep apnea (OSA) but there are limited data on OSA prevalence in cohorts with hypertension comparing dippers and nondippers. We investigated this relationship in a clinic-based cohort of patients with hypertension who were not screened for any pretest possibility of OSA.

METHODS

A total of 100 patients with hypertension aged (mean ± SD) 58 ± 10 years, body mass index 30.5 ± 6.1 kg/m2, and Epworth Sleepiness Scale score 6 ± 4 were included. All underwent overnight attended sleep studies and 24-hour ambulatory blood pressure monitoring. The primary study end-point was OSA prevalence based on the standard criteria of apnea-hypopnea index (AHI) ≥ 15 events/h in patients with dipping and nondipping nocturnal blood pressure.

RESULTS

Results showed 10.5% of dippers and 43.5% of nondippers had an AHI ≥ 15 (chi-square P = .001). In univariate analysis, AHI correlated significantly with blood pressure dip (r = -.26, P < .05), as did ESS (r = -.28, P < .05). In linear regression, AHI predicted the magnitude of blood pressure dip (standardised β = -.288, P = .03), whereas age, body mass index, systolic blood pressure and diastolic blood pressure did not.

CONCLUSIONS

Patients with nondipping nocturnal blood pressure are at high risk of OSA, regardless of symptom profile, which supports the recommendation that such patients should be assessed for co-existing OSA.

The Relationship between Obstructive Sleep Apnea and Alzheimer's Disease

Obstructive sleep apnea (OSA) and Alzheimer's disease (AD) are highly prevalent conditions with growing impact on our aging society. While the causes of OSA are now better characterized, the mechanisms underlying AD are still largely unknown, challenging the development of effective treatments. Cognitive impairment, especially affecting attention and executive functions, is a recognized clinical consequence of OSA. A deeper contribution of OSA to AD pathogenesis is now gaining support from several lines of research. OSA is intrinsically associated with disruptions of sleep architecture, intermittent hypoxia and oxidative stress, intrathoracic and hemodynamic changes as well as cardiovascular comorbidities. All of these could increase the risk for AD, rendering OSA as a potential modifiable target for AD prevention. Evidence supporting the relevance of each of these mechanisms for AD risk, as well as a possible effect of AD in OSA expression, will be explored in this review.

Sleep and Stroke: New Updates on Epidemiology, Pathophysiology, Assessment, and Treatment

PURPOSE OF REVIEW

This review aims to discuss the most recent data on sleep disorders and stroke, highlighting relevant findings for the practicing neurologist or health providers who encounter patients with sleep disorders and stroke.

RECENT FINDINGS

Sleep apnea and abnormal sleep duration have the strongest association with stroke risk. Possible mechanisms include non-dipping of blood pressure during sleep, hypoxemia or reoxygenation leading to sympathetic activation, hypertension, atrial fibrillation and impaired cerebral hemodynamics. Treatment studies suggest that continuous positive airway pressure (CPAP) for sleep apnea could improve primary prevention of stroke, but data is equivocal for secondary prevention. However, CPAP could improve functional outcomes after stroke.

SUMMARY

Sleep disorders present an opportunity to improve stroke risk and functional outcomes. However, new strategies are needed to determine the patients at high-risk who would most likely benefit from targeted care. Novel methods for phenotyping sleep disorders could provide personalized stroke care to improve clinical outcomes and public health strategies.

Diurnal changes in central blood pressure and pulse pressure amplification in patients with obstructive sleep apnoea

STUDY OBJECTIVES

Recent evidence suggests that compared to peripheral blood pressure (BP), central BP may be more strongly associated with target organ damage and cardiovascular morbidity and mortality. Technological advances now allow the ambulatory measurement of peripheral and central BP over 24 ​h. For the first time, we set out to characterise the diurnal profile of central BP and pulse pressure amplification (PPA) in patients with obstructive sleep apnoea (OSA).

METHODS

In this observational study, patients with moderate to severe OSA underwent 24 ​h central and peripheral BP testing before and after at least 4 weeks of CPAP therapy. Concurrent actigraphy was performed to confirm sleep and wake times.

RESULTS

36 patients were screened, 31 had successful testing (mean (SD) age 45 ​± ​10 years, AHI 58 ​± ​27 events/hr, Office BP 136/89 ​± ​10.7/9.5 ​mmHg, 32% on anti-hypertensives, 77% dippers), 21 completed testing post CPAP. Central systolic and diastolic BP followed the same nocturnal dipping profile as peripheral BP, however the peripheral pulse pressure (PP) narrowed in sleep (-3.2 ​mmHg, p ​< ​0.001), whereas the central PP remained unchanged (0.124 ​mmHg, NS), causing a significant reduction in PPA overnight (-10.7%, p ​< ​0.001). The magnitude of dip in central systolic pressure was less than peripheral systolic pressure (by 2.3 ​mmHg, p ​< ​0.001). After treatment with CPAP, the PPA reduction overnight was attenuated (by -3.3%, p ​= ​0.004).

CONCLUSIONS

In moderate to severe OSA, central BP and PPA reduce overnight during sleep. Further randomised controlled studies are needed to quantify the differential effects of CPAP and anti-hypertensives on central versus peripheral BP.

Sleep and Resistant Hypertension

PURPOSE OF REVIEW

The goal of the present review is to describe the current findings on the association of sleep with resistant hypertension (hypertension that remains uncontrolled despite the use of three or more antihypertensive medications from different classes, including a diuretic).

RECENT FINDINGS

Sleep disturbances, particularly obstructive sleep apnea (OSA), are highly prevalent among adults who have resistant hypertension. Randomized controlled trials indicate that treating OSA has modest effects on blood pressure lowering among those with the highest initial blood pressure. There is a paucity of research on the association of habitual sleep and other sleep disturbances with resistant hypertension. Of note, the most recent observational studies describing the association of OSA with resistant hypertension are comprised primarily of non-white race/ethnic groups who are far more likely to have resistant hypertension. OSA is associated with resistant hypertension, but there is limited data on associations between sleep characteristics and resistant hypertension. Future studies should investigate whether treating OSA can reduce disparities in resistant hypertension and whether other aspects of sleep also contribute to resistant hypertension.

Mild-to-moderate sleep apnea is associated with incident hypertension: age effect

STUDY OBJECTIVES

Mild-to-moderate obstructive sleep apnea (OSA) is highly prevalent in the general population; however, previous studies on its association with incident hypertension are mixed. We examined the association between mild and moderate OSA and incident hypertension in a large random general population sample.

METHODS

From 1741 adults of the Penn State Cohort, 744 adults without hypertension or severe OSA (i.e. apnea/hypopnea index [AHI] ≥ 30 events/hour) were followed-up after 9.2 years. Mild OSA was defined as an AHI of 5 to 14.9 events/hour (n = 71), while moderate OSA as an AHI of 15 to 29.9 events/hour (n = 32). Incident hypertension was defined by a self-report of receiving antihypertensive medication and/or history of a diagnosis since their baseline study.

RESULTS

After adjusting for multiple potential confounders, mild-to-moderate OSA was significantly associated with increased risk of incident hypertension (overall hazard ratio [HR] = 2.94, 95% confidence interval (CI) = 1.96-4.41; HR = 3.24, 95% CI = 2.08-5.03 for mild OSA and HR = 2.23, 95% CI = 1.10-4.50 for moderate OSA). Importantly, this association was modified by age (p-interaction < 0.05); while strong in young and middle-aged adults (HR = 3.62, 95% CI = 2.34-5.60), the association was lost in adults older than 60 years (HR = 1.36 95% CI = 0.50-3.72). Furthermore, the association of mild-to-moderate OSA with components of metabolic syndrome was strongest in young and middle-aged adults.

CONCLUSIONS

Mild-to-moderate OSA, even when asymptomatic, is associated with increased risk of incident hypertension, but the strength of association significantly decreases with age. Although older participants with asymptomatic mild-to-moderate OSA are not at significant risk of developing hypertension, early detection and intervention, including improving metabolic indices, is especially warranted in young and middle-aged adults.

Untreated Obstructive Sleep Apnea Is Associated With Myocardial Injury Independent of Blood Pressure Control in Hypertension

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) and hypertension are independent risk factors of cardiovascular morbidities. This study aims to investigate the relationship between OSA, blood pressure (BP) control, and myocardial injury in patients with difficult-to-control hypertension.

METHODS

Patients with hypertension who required three or more medications were prospectively recruited at a tertiary referral center. In-laboratory polysomnography, followed by blood tests for fasting glucose, glycated hemoglobin, lipids, high-sensitivity troponin I (hsTnI), B-type natriuretic peptide (BNP), C-reactive protein, and advanced oxidation protein products were performed. After polysomnography, 24-hour ambulatory BP monitoring was arranged.

RESULTS

A total of 98 participants were analyzed, with mean age 51 ± 9 years and body mass index 30 ± 5 kg/m². Previously undiagnosed severe OSA (apneahypopnea index [AHI] ≥ 30 events/h) was present in 51 patients (52%). hsTnI was negatively correlated with nocturnal dip in systolic BP (r = -.205, P = .048). After controlling for confounders, including BP control, AHI and oxygen desaturation index (ODI) were positively correlated with hsTnI (r = .282, P = .009 and r = .279, P = .010, respectively) and C-reactive protein (r = .302, P = .005 and r = .285, P = .008, respectively), but not with BNP or advanced oxidation protein products. Age, ODI, and loss of nocturnal systolic BP dip were significant determinants of hsTnI level (β = .225, P = .022; β = .293, P = .003; and β = -.215, P = .029; R² = .151). Age, female sex, 24-hour mean diastolic BP, and metabolic syndrome, but not indices of apnea severity, were predictors of BNP level.

CONCLUSIONS

Unrecognized severe OSA was common in patients with difficult-to-control hypertension, and OSA severity was associated with myocardial injury, independent of BP control with medications.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov, Title: A Cross-sectional Study of the Occurrence and Effect of Obstructive Sleep Apnea in Subjects With Resistant Hypertension, Identifier: NCT00843583, URL: https://clinicaltrials.gov/ct2/show/NCT00843583.

Chronotherapy for Hypertension

PURPOSE OF REVIEW

Given the emerging knowledge that circadian rhythmicity exists in every cell and all organ systems, there is increasing interest in the possible benefits of chronotherapy for many diseases. There is a well-documented 24-h pattern of blood pressure with a morning surge that may contribute to the observed morning increase in adverse cardiovascular events. Historically, antihypertensive therapy involves morning doses, usually aimed at reducing daytime blood pressure surges, but an absence of nocturnal dipping blood pressure is also associated with increased cardiovascular risk.

RECENT FINDINGS

To more effectively reduce nocturnal blood pressure and still counteract the morning surge in blood pressure, a number of studies have examined moving one or more antihypertensives from morning to bedtime dosing. More recently, such studies of chronotherapy have studied comorbid populations including obstructive sleep apnea, chronic kidney disease, or diabetes. Here, we summarize major findings from recent research in this area (2013-2017). In general, nighttime administration of antihypertensives improved overall 24-h blood pressure profiles regardless of disease comorbidity. However, inconsistencies between studies suggest a need for more prospective randomized controlled trials with sufficient statistical power. In addition, experimental studies to ascertain mechanisms by which chronotherapy is beneficial could aid drug design and guidelines for timed administration.