Resistant hypertension and obstructive sleep apnea in the primary-care setting

Controversies in Hypertension V: Resistant and Refractory Hypertension

Apparent resistant hypertension, defined as uncontrolled office blood pressure despite ≥ 3 antihypertensive medications including a diuretic or use of ≥ 4 medications regardless of blood pressure, occurs in ≤ 15% of treated hypertensives. Apparent refractory hypertension, defined as uncontrolled office pressure despite use of 5 or more medications including a diuretic, occurs in ≤ 10% of resistant cases. Both are associated with increased comorbidity and enhanced cardiovascular risk. To rule out pseudo-resistant or pseudo-refractory hypertension, employ guideline-based methodology for obtaining pressure, maximize the regimen, rule out white-coat effect, and assess adherence. True resistant hypertension is characterized by volume overload and aldosterone excess, refractory by enhanced sympathetic tone. Spironolactone is the preferred agent for resistance, with lower doses. Spironolactone, potassium binders, or both, are preferred if the estimated glomerular filtration rate is below 45. If significant albuminuria, finerenone is indicated. The optimal treatment of refractory hypertension is unclear, but sympathetic inhibition (α-β blockade, centrally acting sympathoinhibitors, or both) seems reasonable. Renal denervation has shown minimal benefit for resistance, but its role in refractory hypertension remains to be defined.

Association of modifiable risk factors with obstructive sleep apnea: a Mendelian randomization study

BACKGROUND

The risk factors involved in obstructive sleep apnea (OSA) have not been clearly identified yet. We attempted to systematically investigate genetically predicted modifiable risk factors and lifestyle behaviors associated with OSA.

METHODS

The association between 34 risk factors and OSA was evaluated using the two-sample Mendelian randomization (MR). Genetic variants for risk factors were acquired from European-descent genome-wide studies. Data sources for OSA were extracted from FinnGen study with 16,761 cases and 201,194 controls. The primary analysis chosen was the inverse-variance weighted method.

RESULTS

MR analyses provide evidence of genetically predicted poor overall health rating (odds ratio (OR), 2.82; 95% confidence interval (CI), 1.95-4.08), nap during day (OR, 2.01; 95% CI, 1.37-2.93), high body mass index (BMI) (OR, 1.14; 95% CI, 1.09-1.19), increased body fat mass (OR, 1.83; 95% CI, 1.83-2.05), elevated body water mass (OR, 1.50; 95% CI, 1.31-1.70) and hypertension (OR, 1.81; 95% CI, 1.34-2.45) were associated with higher OSA risk, while high education level (OR, 0.55; 95% CI, 0.40-0.75) correlated with reduced OSA risk. Suggestive evidence was obtained for smoking and waist-to-hip ratio (WHR) with higher OSA odds, and vigorous physical activity, and HDL cholesterol with lower OSA odds. After adjusting for BMI using multivariable MR analysis, the effects of smoking, WHR, vigorous physical activity, and HDL-cholesterol were fully attenuated.

CONCLUSIONS

This MR study indicates that overall health rating, nap during day, BMI, body fat mass, body water mass, hypertension, and education are causally associated with the risk of OSA, which means that these modifiable risk factors are key targets for OSA prevention.

When blood pressure refuses to budge: exploring the complexity of resistant hypertension

Resistant hypertension, defined as blood pressure that remains above goal despite using three or more antihypertensive medications, including a diuretic, affects a significant proportion of the hypertensive population and is associated with increased cardiovascular morbidity and mortality. Despite the availability of a wide range of pharmacological therapies, achieving optimal blood pressure control in patients with resistant hypertension remains a significant challenge. However, recent advances in the field have identified several promising treatment options, including spironolactone, mineralocorticoid receptor antagonists, and renal denervation. In addition, personalized management approaches based on genetic and other biomarkers may offer new opportunities to tailor therapy and improve outcomes. This review aims to provide an overview of the current state of knowledge regarding managing resistant hypertension, including the epidemiology, pathophysiology, and clinical implications of the condition, as well as the latest developments in therapeutic strategies and future prospects.

Relationship Between Risks for Obstructive Sleep Apnea, Resistant Hypertension, and Aldosterone Among African American Adults in the Jackson Heart Study

BACKGROUND

African Americans have a higher prevalence of resistant hypertension compared with Caucasians. Racial differences in obstructive sleep apnea (OSA) and increased aldosterone level may explain the racial disparity in resistant hypertension prevalence. Therefore, the purpose of this study is to investigate if aldosterone level and hypertension status differ by risks for OSA (e.g., obesity, loud snoring, and daytime sleepiness) and how aldosterone level varies with hypertension severity and control among African Americans.

METHODS

A cross-sectional analysis was performed using baseline data on 5,052 African American adults in the Jackson Heart Study to investigate the relationships of interest using multivariable linear and multinomial logistic regression models adjusted for potential confounders. Risks for OSA were defined by a "risk score" consisting of the number of risks for OSA.

RESULTS

Of the 5,052 participants, 623 had no risks for OSA. Body mass index was the highest among those with a risk score of 6. About 39% of the sample had no hypertension, 29% had controlled hypertension, 26% had uncontrolled hypertension, and 6% had resistant hypertension. Higher odds of having uncontrolled hypertension or resistant hypertension were present in those with a higher risk score compared with those without risks for OSA. Log-aldosterone level increased with each additional risk for OSA (P-trend <0.05). Similarly, log-aldosterone also increased with more severe hypertension (P-trend <0.001). The highest aldosterone level was found in those with resistant hypertension that was inadequately controlled with medications.

CONCLUSIONS

Risks for OSA were positively associated with resistant hypertension and higher aldosterone level in African American adults.

Prevalence, predictors, and outcomes of both true- and pseudo-resistant hypertension in the action to control cardiovascular risk in diabetes trial: a cohort study

Resistant hypertension (RH) has been poorly studied due to the difficulty in distinguishing it from nonadherence-the exclusion of which is necessary to accurately diagnose RH. Therefore, little is known about the prevalence, predictors, and outcomes of true RH. We evaluated 1838 patients from the standard blood pressure (BP) arm of the Action to Control Cardiovascular Risk in Diabetes Trial. We classified patients into three groups: "true RH", "pseudo-RH" (i.e., patients with BP levels that would classify them as RH but who were non-adherent), and "other" (i.e., those who could not be classified as having "true RH" or "pseudo-RH"). We examined predictors of true and pseudo-RH and the relationship between true RH and the composite outcome of nonfatal MI, nonfatal stroke, or cardiovascular death. Among 1838 participants with complete information, 489 (26.6%) met the definition of true RH, and 94 (16.1%) RH patients had "pseudo-RH" on ≥1 visit over the first 12 months. Predictors of RH included: baseline SBP ≥ 160 mmHg (OR = 8.79; 95% CI: 5.70-13.68) and baseline SBP between 140-159 (OR = 2.91; 95% CI: 2.13-4.00) compared to SBP < 140, additional baseline BP medication (OR = 3.40; 95% CI: 2.83-4.11), macroalbuminuria (OR = 2.35; 95% CI: 1.50-3.67), CKD (OR = 1.53; 95% CI: 0.99-2.33), history of stroke (OR = 1.73; 95% CI: 1.04-2.82), and black race (OR = 1.39; 95% CI: 1.02-1.88); the cross-validated C-statistic was 0.80. "True RH" patients had a 65% increased hazard in composite outcome (HR = 1.65; 95% CI: 1.13-2.42). In conclusion, the majority of patients classified as having RH had "true RH," which was more common among those who are black, have macroalbuminuria, CKD, stroke, higher baseline SBP, and are taking more baseline antihypertensives. These patients are at increased risk for cardiovascular and mortality events.

Nonpharmacological Management of Resistant Hypertension

PURPOSE OF REVIEW

In the United States (US), 46% of adults have hypertension (systolic blood pressure ≥ 130 mmHg, diastolic blood pressure ≥ 80 mmHg). Approximately, 16% of patients with hypertension have apparent treatment-resistant hypertension (aTRH) and the incidence of true resistant hypertension (RHT) is thought to be much lower (~ 2%). These patients with RHT are at a higher risk for adverse events and worse clinical outcomes.

RECENT FINDINGS

Although lifestyle interventions have proven to be effective as the first line of defense in treating hypertension, their role in the management of patients with RHT is not well established. Despite fewer in number, available studies examining lifestyle interventions in patients with RHT do indeed show promising results. In this review, we aim to discuss the role of common lifestyle interventions such as physical activity, exercise, weight loss, and dietary modifications on blood pressure control in patients with RHT.

Obstructive sleep apnea, hypertension, resistant hypertension and cardiovascular disease

Obstructive sleep apnea (OSA) is one of the most common causes of hypertension (HTN) and cardiovascular disease (CVD). It is also a quite common underlying factor in resistant HTN (RHTN). The main etiological factor of OSA is obesity, which is a rapidly growing global epidemic. To control obesity, patients should be encouraged by health care professionals to lose weight and be educated about weight loss strategies such as lifestyle modifications, which include regular exercise, low-calorie diet, low sodium intake, smoking cessation, and decreased alcohol consumption. This review also emphasizes the importance of screening for OSA as the major underlying cause of essential, and RHTN, which can lead to CVD and can cause end-organ damage. It also stresses the importance of using continuous positive airway pressure (CPAP) and its beneficial effects, along with other antihypertensive regimens, in treating HTN, and RHTN. Treatment with CPAP therapy decreases sympathetic activity, high blood pressure (BP), heart rate, and CVD as well as its associated mortality.

Resistant/Refractory Hypertension and Sleep Apnoea: Current Knowledge and Future Challenges

Hypertension is one of the most frequent cardiovascular risk factors. The population of hypertensive patients includes some phenotypes whose blood pressure levels are particularly difficult to control, thus putting them at greater cardiovascular risk. This is especially true of so-called resistant hypertension (RH) and refractory hypertension (RfH). Recent findings suggest that the former may be due to an alteration in the renin-angiotensin-aldosterone axis, while the latter seems to be more closely related to sympathetic hyper-activation. Both these pathophysiological mechanisms are also activated in patients with obstructive sleep apnoea (OSA). It is not surprising, therefore, that the prevalence of OSA in RH and RfH patients is very high (as reflected in several studies) and that treatment with continuous positive airway pressure (CPAP) manages to reduce blood pressure levels in a clinically significant way in both these groups of hypertensive patients. It is therefore necessary to incorporate into the multidimensional treatment of patients with RH and RfH (changes in lifestyle, control of obesity and drug treatment) a study of the possible existence of OSA, as this is a potentially treatable disease. There are many questions that remain to be answered, especially regarding the ideal combination of treatment in patients with RH/RfH and OSA (drugs, renal denervation, CPAP treatment) and patients' varying response to CPAP treatment.

The Potential Role of Obstructive Sleep Apnoea in Refractory Hypertension

PURPOSE OF REVIEW

This review seeks to present an overview of the recently found association between refractory hypertension (RfH) and obstructive sleep apnoea (OSA).

RECENT FINDINGS

RfH was recently defined as an extreme phenotype of resistant hypertension characterized by the lack of blood pressure control despite using ≥ 5 antihypertensive drugs at optimal doses. Current data support that the pathophysiological pathway of both types of hypertension is different. The main mechanism involved in resistant hypertension is fluid retention whereas in the case of RfH is the sympathetic over-activity. OSA is now recognized as a cause of hypertension (especially in the case of difficult-to-treat hypertension). It seems that the biological mechanism linking OSA and arterial hypertension is the sympathetic over-activity related to the respiratory events (apnoeas and hypopnoeas) during the night. So, it is not surprising that, although the literature is scarce, some studies have found a very high prevalence of OSA and an excess of sympathetic activity in patients with RfH. Finally, a very recent study demonstrated that continuous positive airway pressure (CPAP) treatment, which controls sympathetic activation in OSA patients, achieves very significant reductions in blood pressure levels in RfH patients, even greater than in those with resistant (non-refractory) hypertension. The prevalence of OSA in patients with RfH is very high. CPAP treatment achieves a clinically significant reduction in blood pressure levels in those patients with RfH (especially in night readings). Patients with RfH must be sent to a sleep unit for a study.

Resistant Hypertension: Detection, Evaluation, and Management: A Scientific Statement From the American Heart Association

Resistant hypertension (RH) is defined as above-goal elevated blood pressure (BP) in a patient despite the concurrent use of 3 antihypertensive drug classes, commonly including a long-acting calcium channel blocker, a blocker of the renin-angiotensin system (angiotensin-converting enzyme inhibitor or angiotensin receptor blocker), and a diuretic. The antihypertensive drugs should be administered at maximum or maximally tolerated daily doses. RH also includes patients whose BP achieves target values on ≥4 antihypertensive medications. The diagnosis of RH requires assurance of antihypertensive medication adherence and exclusion of the "white-coat effect" (office BP above goal but out-of-office BP at or below target). The importance of RH is underscored by the associated risk of adverse outcomes compared with non-RH. This article is an updated American Heart Association scientific statement on the detection, evaluation, and management of RH. Once antihypertensive medication adherence is confirmed and out-of-office BP recordings exclude a white-coat effect, evaluation includes identification of contributing lifestyle issues, detection of drugs interfering with antihypertensive medication effectiveness, screening for secondary hypertension, and assessment of target organ damage. Management of RH includes maximization of lifestyle interventions, use of long-acting thiazide-like diuretics (chlorthalidone or indapamide), addition of a mineralocorticoid receptor antagonist (spironolactone or eplerenone), and, if BP remains elevated, stepwise addition of antihypertensive drugs with complementary mechanisms of action to lower BP. If BP remains uncontrolled, referral to a hypertension specialist is advised.

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.

Resistant Hypertension: Diagnosis and Management

Resistant hypertension is defined as high blood pressure requiring 3 or more medications for adequate control or controlled blood pressure requiring 4 or more medications. Considering the growing prevalence of hypertension and the strong link with cardiovascular disease, it is vital to understand the causes and treatment of resistant hypertension. This review article starts with an overview of the prevalence and little-known pathophysiology of resistant hypertension. Afterward, we discuss the evaluation and management of suspected secondary resistant hypertension in 2 broad categories: pseudoresistant hypertension and true resistant hypertension. Strategies for the identification and management of pseudoresistant hypertension are addressed. In addition, causes of true resistant hypertension, such as obstructive sleep apnea, primary aldosteronism, and renal artery stenosis, are examined along with their respective treatments. Finally, treatment of resistant hypertension is reviewed including pharmacologic treatments and novel procedural interventions for resistant hypertension. Overall, the review hopes to provide practitioners with a cohesive approach for the diagnosis and treatment of resistant hypertension.

Culturally tailored, peer-based sleep health education and social support to increase obstructive sleep apnea assessment and treatment adherence among a community sample of blacks: study protocol for a randomized controlled trial

BACKGROUND

Compared to whites, blacks are at increased risk for obstructive sleep apnea (OSA) yet less likely to adhere to physician-recommended sleep assessment and treatment. Poor OSA health literacy and lack of social support to navigate the current healthcare system are two potential barriers to adequate OSA care. This study is designed to address these barriers by evaluating the effectiveness of a peer-based sleep health education program on adherence to OSA assessment and treatment among blacks at risk for OSA.

METHOD/DESIGN

In a two-arm, randomized controlled trial, we will ascertain the effectiveness of peer-based sleep health education and social support in increasing OSA evaluation and treatment rates among 398 blacks at low to high OSA risk. Participants at risk of OSA will receive quality controlled, culturally, and linguistically tailored peer education based on Motivational Enhancement principles over a period of 12 months. During this 12-month period, participants are encouraged to participate in a sleep home study to determine risk of OSA and, if found to be at risk, they are invited to undergo a diagnostic sleep assessment at a clinic. Participants who are diagnosed with OSA and who are prescribed continuous positive airway pressure treatment will be encouraged, through peer-based education, to adhere to recommended treatment. Recruitment for the project is ongoing.

DISCUSSION

The use of a culturally tailored sleep health education program, peer health educators trained in sleep health, and home-based sleep assessment are novel approaches in improving OSA assessment and treatment adherence in blacks who are significantly at risk for OSA. Empirical evidence from this trial will provide clinical and population level solutions on how to improve and increase assessment and treatment of OSA among blacks.

TRIAL REGISTRATION

NCT02427815 . Registered on 20 April 2015. ClinicalTrials.gov title: Sleep Health Education and Social Support Among Blacks With OSA.

Sleep Disorders and Symptoms in Blacks with Metabolic Syndrome: The Metabolic Syndrome Outcome Study (MetSO)

Introduction

Sleep disturbance is a major public health issue and is comorbid with the cluster of conditions associated with metabolic syndrome (MetS). Our study explored the presence of sleep disturbance, including daytime sleepiness, the risk for obstructive sleep apnea (OSA), and insomnia symptoms, in a cohort of adult Black men and women with MetS.

Methods

Patients (n=1,013) from the Metabolic Syndrome Outcome Study (MetSO), 2009-2012, met criteria for MetS based on guidelines from the National Cholesterol Education Program's Adult Treatment Panel and provided sociodemographic data and the Apnea Risk Evaluation System (ARES) questionnaire to assess OSA risk, sleep characteristics, and physician-reported diagnosis of a sleep disorder.

Results

Prevalence of the components of MetS included: diabetes (60%); obesity (67%); hypertension (94%); and dyslipidemia (74%). Based on the ARES, 49% were at risk for OSA. Of all study patients, slightly more than half (53%) reported feeling sleepy during the day, and 10% reported an insomnia diagnosis. The most common sleep disturbance reported by 46% of the patients was early morning awakenings (EMA). This was closely followed by 42% who reported difficulty staying asleep (DSA) and 38% reporting difficulty falling asleep (DFA). Seventy percent reported short sleep (≤ 6 hours), whereas a minority (19%) reported long sleep (≥ 9 hours). Only 12% used sleep aids. Women, compared with men, reported greater daytime sleepiness, greater DFA, and greater DSA (57% vs 45%; 41% vs 32.4%; 45% vs 37%), respectively.

Conclusion

Blacks with MetS reported insomnia symptoms and insomnia disorder, use of sleep aids, feeling sleepy during the day, and inadequate sleep durations. The presence of these sleep characteristics suggests that patients with MetS should be referred for further sleep assessment.

Identifying patients at high risk for obstructive sleep apnoea syndrome in Nigeria: A multicentre observational study

Background

Obstructive sleep apnoea is associated with significant health consequences. A significant proportion of hospitalized patients at risk for obstructive sleep apnoea were never identified and referred for polysomnography for diagnosis. The objective of this study was to determine the factors associated with high risk for obstructive sleep apnoea and use it to identify patients at risk for the condition in tertiary hospitals in Nigeria.

Methods

This was a multicentre observational study of adult patients hospitalized in three selected hospitals from 15th January to 17th March 2015. Berlin questionnaire and Epworth sleepiness scale were used to assess for obstructive sleep apnoea risk and excessive daytime sleepiness respectively. Additional questions on traditional risk factors for obstructive sleep apnoea were also obtained.

Results

Nine hundred and twenty-six patients were recruited into the study. Respondents' mean age was 44.3 years ± 15.2years, 486 (52.5%) were females and 556 (60.0%) had one or more medical co-morbidity and none of the patients had a previous diagnosis of obstructive sleep apnoea. Factors that were independently associated with high risk for obstructive sleep apnoea include systemic hypertension(aOR-10.33;95%: CI 6.42–16.61), obesity(aOR-7.87;95% CI: 4.33–14.29); excessive daytime sleepiness (aOR-3.77;95% CI :2.28–6.22), tobacco smoking (aOR-2.99;95% CI: 1.76–5.07), snoring in a first-degree relative (aOR-1.83;95% CI: 1.19–2.81); and the use of sedative (aOR-1.82;95% CI: 1.06–3.15).

Conclusions

This study shows that patients with systemic hypertension, obesity, excessive daytime sleepiness, history of smoking, snoring in a first-degree relative and use of sedatives are at high risk of obstructive sleep apnoea. None of the patients at high risk had a previous diagnosis of sleep apnoea by a physician, highlighting the diagnostic challenges of this condition. The results of this study will assist health care professionals in early identification of individuals at risk of obstructive sleep apnoea and subsequent referral for a sleep study.

Review of and Updates on Hypertension in Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) is a prevalent sleep disorder as is hypertension (HTN) in the 21st century with the rising incidence of obesity. Numerous studies have shown a strong association of OSA with cardiovascular morbidity and mortality. There is overwhelming evidence supporting the relationship between OSA and hypertension (HTN). The pathophysiology of HTN in OSA is complex and dependent on various factors such as sympathetic tone, renin-angiotensin-aldosterone system, endothelial dysfunction, and altered baroreceptor reflexes. The treatment of OSA is multifactorial ranging from CPAP to oral appliances to lifestyle modifications to antihypertensive drugs. OSA and HTN both need prompt diagnosis and treatment to help address the growing cardiovascular morbidity and mortality due to these two entities.

Effect of Maladaptive Beliefs and Attitudes about Sleep among Community-dwelling African American Men at Risk for Obstructive Sleep Apnea

This study compared differences in both maladaptive beliefs and attitudes about sleep between African American (heareafter referred to as black) men at risk for obstructive sleep apnea (OSA) and those without OSA risk.

Correlation of upper airway radiographic measurements with risk status for obstructive sleep apnea syndrome in young dental patients

OBJECTIVE

The aim of the present study is to compare radiographic measurements of the upper airway (UA) in young adult patients with different levels of risk status for obstructive sleep apnea syndrome.

STUDY DESIGN

The study included 50 patients between 18 and 30 years of age who were referred for dental examination and evaluation of impacted third molars. Case record forms, including habit history, along with the Berlin Questionnaire and the Epworth Sleepiness Scale, were completed by the patients and their relatives. According to the answers, 25 low-risk patients and 25 high-risk patients were selected. Cephalometric radiographs and cone beam computed radiography images were obtained for radiographic analysis when the patients were admitted into the study.

RESULTS

There were significant differences in body mass index, neck circumference measurements, Epworth score, and smoking status between risk groups. There were significant differences for UA measurements on radiographic evaluation. Body mass index (BMI) was found to be correlated positively with neck circumference and Epworth scores and negatively with UA measurements for all patients. Velopharyngeal measurements showed the highest correlation with Epworth scores, BMI, and neck circumference.

CONCLUSIONS

The radiographic findings correlated with the survey results. Our data suggest that radiographic measurements of UA may be used as a predictor of risk for obstructive sleep apnea syndrome in a young population.

Tailored approach to sleep health education (TASHE): study protocol for a web-based randomized controlled trial

BACKGROUND

Obstructive sleep apnea (OSA) is a sleep disorder that disproportionately affects African Americans (hereafter referred to as blacks). Moreover, blacks may underutilize sleep services including overnight polysomnography. Thus, OSA among blacks may go undiagnosed and untreated, which has significant health consequences, including hypertension, diabetes, cognitive impairment, and daytime sleepiness.

DESIGN AND METHODS

This two-arm randomized controlled trial will assign 200 participants to a culturally and linguistically tailored web-based sleep educational platform. The website will be developed to ensure that the content is user friendly and that it is readable and acceptable by the target community. Participants will receive login information to a password-protected website and will have access to the website for 2 months. Study assessments will be collected at baseline, 2 months (post-enrollment) and at 6 months (follow-up). We will use qualitative and quantitative methods to develop tailored materials and to ascertain whether tailored materials will increase OSA knowledge and OSA health literacy by comparing blacks exposed to tailored materials versus those exposed to standard sleep health literature. We hypothesize that exposure to tailored OSA information will improve OSA health literacy.

DISCUSSION

Few studies have investigated the racial/ethnic disparities in relation to OSA screening and treatment comparing blacks and whites. Moreover, we know of no interventions designed to increase OSA knowledge and health literacy among blacks. Use of the Internet to disseminate health information is growing in this population. Thus, the Internet may be an effective means to increase OSA health literacy, thereby potentially increasing utilization of sleep-related services in this population.

TRIAL REGISTRATION

The study is registered at clinicaltrials.gov, reference number NCT02507089 . Registered on 21 July 2015.

Resistant Hypertension and Sleep Duration among Blacks with Metabolic Syndrome MetSO

INTRODUCTION

Resistant hypertension (RHTN) is an important condition affecting 29% of the hypertensive population in the U.S., especially among blacks. Sleep disturbances, like obstructive sleep apnea, insomnia, and short sleep duration, are increasingly recognized as underlying modifiable factors for RHTN. We evaluated associations of RHTN with short sleep duration among blacks with metabolic syndrome.

METHODS

Data from the Metabolic Syndrome Outcome Study (MetSO), a NIH-funded cohort study characterizing metabolic syndrome (MetS) among blacks were analyzed. MetS was defined according to criteria from the Adult Treatment Panel (ATP III). RHTN was defined according to guidelines from the American Heart Association. Short sleep was defined as self-reported sleep duration <7 hrs experienced during a 24-hour period.

RESULTS

Analysis was based on 1,035 patients (mean age: 62±14years; female: 69.2%). Of the sample, 90.4% were overweight /obese; 61.4% had diabetes; 74.8% had dyslipidemia; 30.2% had a history of heart disease; and 48% were at high risk for obstructive sleep apnea. Overall, 92.6% reported physician-diagnosed hypertension (HTN) and 20.8% met criteria for RHTN. Analyses showed those with RHTN were more likely to be short sleepers (26.8% vs. 14.9%, p< 0.001). Based on logistic regression analysis, adjusting for effects of age, sex, and medical comorbidities, patients with metabolic syndrome and RHTN had increased odds of being short sleepers (OR = 1.95, 95% CI: 1.28-2.97, p = 0.002).

CONCLUSION

Among blacks with metabolic syndrome, patients meeting criteria for resistant hypertension showed a twofold greater likelihood of being short sleepers, prompting the need for sleep screening in this vulnerable population.

Comparisons of sleep apnoea rate and outcomes among patients with resistant and non-resistant hypertension

BACKGROUND AND OBJECTIVE

We directly compared sleep apnoea (SA) rates and risk of cardiovascular and mortality outcomes among SA patients with resistant hypertension (RH) and non-RH within a large diverse hypertension population.

METHODS

A retrospective cohort study between 1 January 2006 and 31 December 2010 among hypertensive adults (age ≥ 18 years) was performed within an integrated health system. Rates of SA in RH and non-RH were determined. Multivariable logistic regression analyses were used to calculate OR for SA. Cox proportional hazard modelling was used to estimate hazard ratios (HRs) for cardiovascular and mortality outcomes between SA in RH versus SA in non-RH adjusting for age, gender, race, BMI, chronic kidney disease and other comorbidities.

RESULTS

SA was identified in 33 682 (7.2%) from 470 386 hypertensive individuals. SA in RH accounted for 5806 (9.6%) compared to SA in non-RH 27 876 individuals (6.8%). Multivariable OR (95% CI) for SA was 1.16 (1.12, 1.19), 3.57 (3.47, 3.66) and 2.20 (2.15, 2.25) for RH versus non-RH, BMI ≥ 30, and males, respectively. Compared to SA in non-RH individuals, SA in RH had a multivariable adjusted HR (95% CI) of 1.24 (1.13, 1.36), 1.43 (1.28, 1.61), 0.98 (0.85, 1.12) and 1.04 (0.95, 1.14) for ischaemic heart event (IHE), congestive heart failure (CHF), stroke and mortality, respectively.

CONCLUSION

We observed a modest increase in likelihood for SA among RH compared to non-RH patients. Risks for IHE and CHF were higher for SA in RH compared to SA in non-RH patients; however, there were no differences in risk for stroke and mortality.

Relationship Between OSA and Hypertension

There is a bidirectional association between OSA and systemic hypertension. The strengths of this relationship appear to be modulated by factors such as age, sex, and somnolence. The 24-h BP circadian pattern also appears to be influenced by OSA. Patients with this syndrome exhibit a high prevalence of nondipping or riser circadian patterns, which are related to clinical and subclinical organ damage in the heart and brain. However, the influence of OSA on nocturnal hypertension development has not yet been clarified. A special area of interest is the recognized relationship between OSA and resistant hypertension. The majority of patients with resistant hypertension suffer OSA. CPAP treatment significantly reduces BP in such patients and could play a clinical role in the management of BP in these patients. Several meta-analyses have demonstrated a concordant mild effect of CPAP on systemic hypertension. This effect is related to CPAP compliance, somnolence status, and baseline BP. The effects of oral appliances on BP in patients with OSA must be evaluated in randomized controlled trials. In the absence of additional data reported by clinical studies on other antihypertensive drug treatments, diuretics, particularly antialdosteronic diuretic agents, should be considered the first-line antihypertensive drug treatment in patients with OSA. By reducing parapharyngeal edema and secondary upper airway obstruction, these drugs appear to improve OSA severity and also to reduce BP.

Uncontrolled blood pressure and risk of sleep apnea among blacks: findings from the Metabolic Syndrome Outcome (MetSO) study

Uncontrolled blood pressure (BP) is linked to increased risk of obstructive sleep apnea (OSA). However, few studies have assessed the impact of this relationship among blacks with metabolic syndrome (MetS). Data for this study were collected from 1035 blacks (mean age=62±13 years) enrolled in the Metabolic Syndrome Outcome study. Patients with a score ⩾6 on the Apnea Risk Evaluation System were considered at risk for OSA. Of the sample, 77.1% were low-to-high OSA risk and 92.3% were hypertensive, of which 16.8% had uncontrolled BP levels. Analysis also showed that 60.4% were diabetic, 8.9% had a stroke history, 74.3% had dyslipidemia, 69.8% were obese and 30.9% had a history of heart disease. Logistic regression analyses were employed to investigate associations between uncontrolled BP and OSA risk, while adjusting for known covariates. Findings showed that uncontrolled BP independently increased the odds of OSA risk twofold (odds ratio=2.02, 95% confidence interval=1.18-3.48, P<0.05). In conclusion, our findings show that uncontrolled BP was associated with a twofold greater risk of OSA among blacks, suggesting that those with MetS and who have uncontrolled BP should be screened for the presence of OSA.

Predictors of Obstructive Sleep Apnea Risk among Blacks with Metabolic Syndrome

INTRODUCTION

Identification of risk factors for obstructive sleep apnea (OSA) is important to enable comprehensive intervention to reduce OSA-related cardiovascular disease (CVD). The metabolic syndrome outcome study (MetSO) provides a unique opportunity to address these factors. This study investigated risk of OSA among blacks with metabolic syndrome.

METHODS

The present study utilized data from MetSO, an NIH-funded cohort study of blacks with metabolic syndrome. A total of 1,035 patients provided data for the analysis. These included sociodemographic factors, health risks, and medical history. Physician-diagnosed conditions were obtained using an electronic medical record system (Allscripts, Sunrise Enterprise). Patients were diagnosed with metabolic syndrome using criteria articulated in the joint interim statement for harmonizing the metabolic syndrome. Patients with a score ≥6 on the Apnea Risk Evaluation System (ARES) questionnaire were considered at risk for OSA. Obesity is defined by body mass index (BMI ≥ 30 kg/m2).

RESULTS

Of the 1,035 patients screened in the MetSO cohort, 48.9% were at high risk for OSA. Using multivariate-adjusted logistic regression analysis, we observed that obesity was the strongest predictor of OSA risk (OR=1.59, 95%CI=1.24-2.04, p<0.0001). This finding remained significant even after adjustment for known covariates including blood pressure, low-density lipoprotein, high-density lipoprotein, and glucose levels (OR=1.44, 95%CI=1.11-1.86, p<0.001).

CONCLUSION

Blacks in the MetSO cohort are at greater OSA risk, relative to the adult population in developed countries. Consistent with previous observations, obesity proved the strongest independent predictor of OSA risk among blacks with metabolic syndrome.

Associations between sleep disturbances and diabetes mellitus among blacks with metabolic syndrome: Results from the Metabolic Syndrome Outcome Study (MetSO)

INTRODUCTION

The association between sleep disturbances and cardiometabolic diseases has been understudied in blacks with metabolic syndrome.

METHODS

This study is a cross-sectional analysis of the Metabolic Syndrome Outcome Study (MetSO) trial. We assessed insomnia symptoms, sleep duration, and risk for sleep apnea. Multivariate logistic regression models evaluated the association between sleep disturbances with diabetes mellitus (DM) and the combined outcomes of DM and hypertension as well as DM and dyslipidemia.

RESULTS

The sample consisted of 1,013 participants, mean age of 62 ± 14 years and 61% female. DM was diagnosed in 60% of the sample. Sleep apnea risk was observed in 48% of the sample, while 10% had insomnia symptoms and 65% reported short sleep duration (< 6 hours). Sleep apnea risk, but not insomnia or sleep duration, was associated with DM (OR 1.66; 95% CI 1.21-2.28), adjusting for age, sex, income, obesity (BMI ≥ 30 kg/m(2)), tobacco use, alcohol use, hypertension, dyslipidemia, and depression. In fully adjusted models, sleep apnea risk was associated with the combined outcome of DM-hypertension (OR 1.95; 95% CI 1.42-2.69), but not with diabetes-dyslipidemia.

CONCLUSION

We observed a strong association between sleep apnea risk and diabetes mellitus among blacks with metabolic syndrome.

Obstructive sleep apnea risk and psychological health among non-Hispanic blacks in the Metabolic Syndrome Outcome (MetSO) cohort study

INTRODUCTION

This study assessed associations of depression and anxiety with risk of obstructive sleep apnea (OSA) among non-Hispanic blacks in the Metabolic Syndrome Outcome (MetSO) study.

METHOD

A total of 1,035 patients participated. ARES™ score ≥6 defined high OSA risk. Moderate depression was defined by a CES-D score ≥16. Moderate anxiety was measured by a BAI score ≥16.

RESULTS

The mean age was 62 ± 14 years; 70% were female. A total of 93% were diagnosed with hypertension; 61%, diabetes; and 72%, dyslipidemia; 90% were overweight/obese; 33% had a history of heart disease; and 10% had a stroke. Logistic regression analysis, adjusting for age and gender, showed that patients with depression had nearly two-fold increased odds of being at risk for OSA (OR 1.75, 95% CI 1.02-2.98, p < 0.05). Patients with anxiety had three-fold increased odds of being at risk for OSA (OR 3.30, 95% CI 2.11-5.15, p < 0.01). After adjusting for marital status and income, patients with anxiety had a 6% increase in OSA risk (OR 1.06, 95% CI 1.04-1.09, p < 0.05), but depression was no longer significant.

CONCLUSION

Our results suggest that non-Hispanic blacks with metabolic syndrome who experience anxiety and/or depression should be screened for OSA.

Sleep in America: role of racial/ethnic differences

Sleep duration in America has gradually declined over the last four decades and appears to have reached a plateau for the last six years, with recent studies reporting that the population's current average sleep duration is approximately 6 h. In this paper, we examine epidemiologic and community-based data on sleep complaints reported by American adults, specifically addressing the role of race/ethnicity in the subjective report of sleep problems. Subjective and objective findings indicate that black (throughout the text, we use the term black in lieu of African American for there are instances where we refer to individuals with self-ascribed race/ethnicity as black, African American, African, or Caribbean American; the term white is used to denote individuals of European descent). Americans have higher rates of long (≥9 h) and short (≤5 h) sleep than their white counterparts, and this may mediate a higher risk of cardiovascular disease, obesity and diabetes among blacks. In addition, studies show mixed results on sleep complaints among blacks compared to those among other ethnicities. This paper explores factors that may contribute to racial/ethnic differences in sleep including intra-ethnic variation, cultural biases, genetics and psychosocial factors.

Supine fluid redistribution: should we consider this as an important risk factor for obstructive sleep apnea?

INTRODUCTION

Obstructive sleep apnea (OSA) is a common medical disorder affecting at least 2 % of women and 4 % of men living in Western societies. Obesity, older age, male gender, alcohol and sedative use, smoking, craniofacial parameters, and volume overload are some of the risk factors for this disorder.

DISCUSSION

OSA is a known risk factor complicating the course of arterial hypertension, heart failure, and chronic kidney disease. It is important to note that all of the aforementioned comorbid disorders are associated with volume overload. This explains why patients with OSA and comorbid disorders associated with fluid overload can benefit from treatment with diuretics and drugs modulating the renin-angiotensin-aldosterone system. Additionally, patients with heart failure and high sodium intake are at increased risk for OSA, further supporting the complex interrelationship.

CONCLUSIONS

Hemodialysis and renal transplantation can markedly improve the severity of OSA in patients with concomitant kidney disease. Finally, there is a potential of a vicious cycle between OSA and fluid overload disorders, whereby OSA can contribute to the pathogenesis of arterial hypertension, heart failure, and chronic kidney disease, which in turn will significantly contribute to the course OSA.

Race/ethnicity, sleep duration, and diabetes mellitus: analysis of the National Health Interview Survey

BACKGROUND

The effect of race/ethnicity on the risk of diabetes associated with sleep duration has not been systematically investigated. This study assessed whether blacks reporting short (<6 hours) or long (>8 hours) sleep durations were at greater risk for diabetes than their white counterparts. In addition, this study also examined whether the influence of race/ethnicity on associations between abnormal sleep durations and the presence of diabetes were independent of individuals' sociodemographic and medical characteristics.

METHODS

A total of 29,818 Americans (age range: 18-85 years) enrolled in the 2005 National Health Interview Survey, a cross-sectional household interview survey, provided complete data for this analysis.

RESULTS

Of the sample, 85% self-ascribed their ethnicity as white and 15% as black. The average age was 47.4 years, and 56% were female. Results of univariate regression analysis adjusting for medical comorbidities showed that black and white participants who reported short sleep duration (<6 hours) were more likely to have diabetes than individuals who reported sleeping 6 to 8 hours (odds ratios 1.66 and 1.87, respectively). Likewise, black and white participants reporting long sleep duration (>8 hours) had a greater likelihood of reporting diabetes compared with those sleeping 6 to 8 hours (odds ratios 1.68 and 2.33, respectively). Significant interactions of short and long sleep with black and white race were observed. Compared with white participants, greater diabetes risk was associated with being short or long sleepers of black race.

CONCLUSION

The present findings suggest that American short and long sleepers of black race may be at greater risk for diabetes independently of their sociodemographic profile or the presence of comorbid medical conditions, which have been shown to influence habitual sleep durations. Among black individuals at risk for diabetes, healthcare providers should stress the need for adequate sleep.