Cardiovascular risk after hospitalisation for unexplained syncope and orthostatic hypotension

An Investigation of Metabolic Risk Factors and Gut Microbiota in Unexplained Syncope

BACKGROUND

The pathogenesis of many syncopal episodes remains unexplained. Intestinal dysbiosis could be involved in the pathophysiological mechanisms of syncope due to its connection with the central nervous system via the microbiota-gut-brain axis. This pilot study aimed to explore the specific cardiometabolic risk factors and gut microbiota in unexplained syncope (US), compared to other types of syncope, to assess their similarity or verify their different origins.

METHODS

We studied 86 participants with syncope, who were divided into four groups: an orthostatic syncope group (OH, n = 24), a neuromediated syncope group (NMS, n = 26), a cardiological syncope group (CS, n = 9), and an unexplained syncope group (US, n = 27). We evaluated the anthropometric, clinical, and metabolic characteristics of the four groups; the α- and β-diversity; and the differences in the abundance of the microbial taxa.

RESULTS

The US group had a lower incidence of systolic hypertension at the first visit and a lower frequency of patients with nocturnal hypertension than the CS group. Compared to the OH and NMS groups, the US group had a higher incidence of carotid plaques and greater carotid intima-media thickness, respectively. The microbiota differed significantly between the US and CS groups, but not between the US group and the OH or NMS group.

CONCLUSIONS

We observed significant differences in the gut microbiota between CS and US. Future studies are necessary to evaluate the involvement of the gut microbiota in the complex pathogenesis of syncope and whether its analysis could support the interpretation of the pathophysiological mechasnisms underlying some episodes classifiable as US.

Definitive aetiology of unexplained syncope after cardiovascular autonomic tests in a tertiary syncope unit

AIMS

Syncope is a common condition with many possible causes, ranging from benign to life-threatening aetiologies. Establishing a diagnosis can be difficult, and specialized syncope units, using cardiovascular autonomic tests (CATs), including a head-up tilt test, can increase the diagnostic yield. However, up to one-fifth of examined patients have inconclusive CAT results. The aim of the present study was to investigate the predictive value of history, and clinical findings for unexplained syncope after CAT and characterize the group with negative results.

METHODS AND RESULTS

Consecutive syncope patients [n = 2663, 61% women, median age 52 (32-69) years] were evaluated and CAT explained aetiology of syncope in 79% of cases, whereas 21% remained unexplained. Predictors of negative CAT were older age at first syncope (+8% higher odds per 10-year increment, P = 0.042), higher supine heart rate (HR; +12% per 10 b.p.m.; P = 0.003), absence of prodromes (+48%; P < 0.001), hypertension (+45%; P = 0.003), diabetes (+82%; P < 0.001), heart failure (+98%; P = 0.014), and coronary artery disease (+51%; P = 0.027). Compared with vasovagal syncope, patients with negative CAT were older, reported more often the absence of prodromes, and had a higher burden of cardiovascular comorbidities.

CONCLUSION

A cardiovascular autonomic test established the cause of syncope in 79% of patients evaluated in a syncope unit. Syncope without prodromes and cardiovascular comorbidities were significant predictors of failure to reveal an aetiology from assessment by CAT. These are known risk factors for cardiac syncope and patients with inconclusive CAT warrant further investigation.

Adverse childhood experiences are associated with altered cardiovascular reactivity to head-up tilt in young adults

Adverse childhood experiences (ACEs) are associated with greater prevalence of cardiovascular disease and altered acute stress reactivity. The current study investigated the effect of ACEs on hemodynamic and autonomic responses to orthostatic stress imposed by 60° head-up tilt (HUT) in young adults. Two-hundred twenty-six healthy young adults (age = 22.6 ± 1.5 yr; n = 116 females) without cardiovascular disease participated and had complete data. Participants underwent supine blood pressure (BP), R-R interval (RRI), cardiac output (CO), total peripheral resistance (TPR), and cardiovagal baroreflex sensitivity (cvBRS) testing followed by a transition to 60° HUT where measures were reassessed. Childhood adversity exposures were assessed based on categorical exposure and nonexposure to childhood household dysfunction and maltreatment, and <4 and ≥4 types of ACEs. Significantly greater increases in SBP (P < 0.05), DBP, MAP, and TPR (P < 0.01; all) following 60° HUT were observed in individuals with ≥4 compared with those with <4 types of ACEs. Attenuated decreases in RRI and cvBRS were observed in those with ≥4 types of ACEs (P < 0.05). Experiencing ≥4 types of ACEs was associated with augmented BP and TPR reactivity and a blunted decrease in cvBRS in response to 60° HUT in young adults. Results suggest that a reduced vagal response to orthostatic stress is present in those who have experienced ≥4 types of ACEs that may promote autonomic dysfunction. Future research examining the sympathetic and vagal baroreflex branches is warranted.

New horizons in the ageing autonomic nervous system: orthostatic hypotension and supine hypertension

Blood pressure regulation is an automatic, moment-by-moment buffering of the blood pressure in response to physiological changes such as orthostasis, exercise and haemorrhage. This finely orchestrated reflex is called the baroreflex. It is a regulated arc of afferent, central and efferent arms. Multiple physiological changes occur with ageing that can disrupt this reflex, making blood pressure regulation less effective. In addition, multiple changes can occur with ageing-related diseases such as neurodegeneration, atherosclerosis, deconditioning and polypharmacy. These changes commonly result in orthostatic hypotension, hypertension or both, and are consistently associated with multiple adverse outcomes. In this article, we discuss the healthy baroreflex, and physiological and pathophysiological reasons for impaired baroreflex function in older people. We discuss why the common clinical manifestations of orthostatic hypotension and concomitant supine hypertension occur, and strategies for balancing these conflicting priorities. Finally, we discuss strategies for treating them, outlining our practice alongside consensus and expert guidance.

Long-term recurrences and mortality in patients with noncardiac syncope

INTRODUCTION AND OBJECTIVES

There are no in-depth studies of the long-term outcome of patients with syncope after exclusion of cardiac etiology. We therefore analyzed the long-term outcome of this population.

METHODS

For 147 months, we included all patients with syncope referred to our syncope unit after exclusion of a cardiac cause.

RESULTS

We included 589 consecutive patients. There were 313 (53.1%) women, and the median age was 52 [34-66] years. Of these, 405 (68.8%) were diagnosed with vasovagal syncope (VVS), 65 (11%) with orthostatic hypotension syncope (OHS), and 119 (20.2%) with syncope of unknown etiology (SUE). During a median follow-up of 52 [28-89] months, 220 (37.4%) had recurrences (21.7% ≥ 2 recurrences), and 39 died (6.6%). Syncope recurred in 41% of patients with VVS, 35.4% with OHS, and 25.2% with SUE (P=.006). In the Cox multivariate analysis, recurrence was correlated with age (P=.002), female sex (P <.0001), and the number of previous episodes (< 5 vs ≥ 5; P <.0001). Death occurred in 15 (3.5%) patients with VVS, 11 (16.9%) with OHS, and 13 (10.9%) with SUE (P=.001). In the multivariate analysis, death was associated with age (P=.0001), diabetes (P=.007), and diagnosis of OHS (P=.026) and SUE (P=.020).

CONCLUSIONS

In patients with noncardiac syncope, the recurrence rate after 52 months of follow-up was 37.4% and mortality was 6.6% per year. Recurrence was higher in patients with a neuromedial profile and mortality was higher in patients with a nonneuromedial profile.

Outcomes of Primary vs. Delayed Strategy of Implanting a Cardiac Monitor for Unexplained Syncope

Objective: Implantable cardiac monitors (ILR) have an important role in diagnosing unexplained syncope. However, outcomes of primary vs. delayed ILR implantation after initial syncope evaluation have not been explored. Methods: A total of 1705 patients with unexplained syncope were prospectively enrolled in the SYSTEMA (Syncope Study of Unselected Population in Malmö) cohort. Patients who underwent cardiovascular autonomic testing (CAT) and ILR were grouped into those referred to CAT after ILR implantation (primary ILR) and those in whom ILR was indicated after CAT (post-CAT ILR). Results: One-hundred-and-fifteen patients (6.7%) received ILRs. ILR recipients were older (58 vs. 52 years; p = 0.002), had more syncope recurrences (6 vs. 4; p < 0.001), more traumatic falls (72% vs. 53%; p < 0.001), and less prodrome (40% vs. 55%; p = 0.005) than patients without ILRs. During follow-up ≥16 months after ILR, 67 (58%) had normal sinus rhythm, 10 (8.7%) had sinus arrest, 10 (8.7%) AV-block, 13 (11.3%) atrial fibrillation, 9 (7.8%) supraventricular tachycardia, 4 (3.5%) sinus tachycardia and 2 (1.7%) ventricular tachycardia with clinical symptom reproduction. There were 52 patients (45%) in the primary-ILR group and 63 (55%) in the post-CAT ILR group. Proportions of negative ILR monitoring (17/52 vs. 25/63; p = 0.56) and pacemaker implantations (7/52 vs. 15/63; p = 0.23) did not differ between groups. Baseline ECG conduction disorders predicted pacemaker implantation (n = 11/17; odds ratio:10.6; 95%CI: 3.15−35.3; p < 0.001). CAT was more often positive (73% vs. 40%; p < 0.001) in primary-ILR group. Conclusions: Primary ILR implantation was associated with more positive CAT compared with delayed ILR implantation, but negative monitoring and pacemaker implantations were not different between groups. ECG conduction disorders predicted subsequent pacemaker implantation.

Orthostatic Hypotension: Management of a Complex, But Common, Medical Problem

Orthostatic hypotension (OH), a common, often overlooked, disorder with many causes, is associated with debilitating symptoms, falls, syncope, cognitive impairment, and risk of death. Chronic OH, a cardinal sign of autonomic dysfunction, increases with advancing age and is commonly associated with neurodegenerative and autoimmune diseases, diabetes, hypertension, heart failure, and kidney failure. Management typically involves a multidisciplinary, patient-centered, approach to arrive at an appropriate underlying diagnosis that is causing OH, treating accompanying conditions, and providing individually tailored pharmacological and nonpharmacological treatment. We propose a novel streamlined pathophysiological classification of OH; review the relationship between the cardiovascular disease continuum and OH; discuss OH-mediated end-organ damage; provide diagnostic and therapeutic algorithms to guide clinical decision making and patient care; identify current gaps in knowledge and try to define future research directions. Using a case-based learning approach, specific clinical scenarios are presented highlighting various presentations of OH to provide a practical guide to evaluate and manage patients who have OH.

Risk stratification of syncope: Current syncope guidelines and beyond

Syncope is an alarming event carrying the possibility of serious outcomes, including sudden cardiac death (SCD). Therefore, immediate risk stratification should be applied whenever syncope occurs, especially in the Emergency Department, where most dramatic presentations occur. It has long been known that short- and long-term syncope prognosis is affected not only by its mechanism but also by presence of concomitant conditions, especially cardiovascular disease. Over the last two decades, several syncope prediction tools have been developed to refine patient stratification and triage patients who need expert in-hospital care from those who may receive nonurgent expert care in the community. However, despite promising results, prognostic tools for syncope remain challenging and often poorly effective. Current European Society of Cardiology syncope guidelines recommend an initial syncope workup based on detailed patient's history, physical examination supine and standing blood pressure, resting ECG, and laboratory tests, including cardiac biomarkers, where appropriate. Subsequent risk stratification based on screening of features aims to identify three groups: high-, intermediate- and low-risk. The first should immediately be hospitalized and appropriately investigated; intermediate group, with recurrent or medium-risk events, requires systematic evaluation by syncope experts; low-risk group, sporadic reflex syncope, merits education about its benign nature, and discharge. Thus, initial syncope risk stratification is crucial as it determines how and by whom syncope patients are managed. This review summarizes the crucial elements of syncope risk stratification, pros and cons of proposed risk evaluation scores, major challenges in initial syncope management, and how risk stratification impacts management of high-risk/recurrent syncope.

Social relationships and the risk of incident heart failure: results from a prospective population-based study of older men

Aims

Limited social relationships, particularly in older adults, have been implicated as a risk factor for cardiovascular disease. However, little is known about the associations between poor social relationships and heart failure incidence.

Methods and results

Prospective study of socially representative men aged 60–79 years drawn from general practices in 24 British towns and followed up for a maximum of 18 years. A total of 3698 participants with no previous diagnosis of heart failure were included. Information on social relationships was based on a combination of marital status, living circumstances, and social contacts with friends and family. These provided information on contact frequency, contact satisfaction, and a social relationship score (low to high) combining frequency and satisfaction with contact. Heart failure included both incidents non-fatal heart failure and death from heart failure. Among 3698 participants, 330 developed heart failure. Men with low compared to high frequency of contact with family and friends had an increased risk of incident heart failure [hazard ratio (HR) 1.59, 95% confidence interval (CI) 1.15–2.18]; this remained statistically significant after adjustment for social class, behavioural, and biological risk factors. Low compared to high scores for satisfaction with contacts was associated with increased risk of heart failure (adjusted HR = 1.54; 95% CI 1.14–2.07). Lower social relationship scores (combining frequency and satisfaction with contact) were associated with greater risk of incident heart failure (adjusted HR = 1.38, 95% CI 1.02–1.87). Marital status and living alone were not significantly associated with heart failure.

Conclusion

Weaker social relationships appear to increase the risk of developing heart failure in older age. Further research is needed to investigate pathways underlying these associations and to test whether interventions to strengthen social relationships can reduce the risk of heart failure.

OUP accepted manuscript

Aims

Methods and results

Conclusion

Risk of incident fractures in individuals hospitalised due to unexplained syncope and orthostatic hypotension

BACKGROUND

Impaired orthostatic blood pressure response and syncope confer a high risk of falls and trauma. The relationship between a history of unexplained syncope and orthostatic hypotension (OH) with subsequent fractures, however, has not been thoroughly examined. In this study, we aimed to investigate the relationship between previous hospital admissions due to unexplained syncope and OH and incident fractures in a middle-aged population.

METHODS

We analysed a large population-based prospective cohort of 30,399 middle-aged individuals (age, 57.5 ± 7.6; women, 60.2%). We included individuals hospitalised due to unexplained syncope or OH as the main diagnosis. Multivariable-adjusted Cox regression analysis was applied to assess the impact of unexplained syncope and OH hospitalisations on subsequent incident fractures.

RESULTS

During a follow-up period of 17.8 + 6.5 years, 8201 (27%) subjects suffered incident fractures. The mean time from baseline and first admission for syncope (n = 493) or OH (n = 406) was 12.6 ± 4.2 years, and the mean age of the first hospitalisation was 74.6 ± 7.4 years. Individuals with incident fractures were older, more likely to be women, and had lower BMI, higher prevalence of prevalent fractures, and family history of fractures. Multivariable-adjusted Cox regression showed an increased risk of incident fractures following hospitalisations due to unexplained syncope (HR 1.20; 95% CI 1.02-1.40; p = 0.025) and OH (HR 1.42; 95% CI 1.21-1.66; p < 0.001) compared with unaffected individuals.

CONCLUSIONS

Individuals hospitalised due to unexplained syncope and orthostatic hypotension have an increased risk of subsequent fractures. Our findings suggest that such individuals should be clinically assessed for their syncope aetiology, with preventative measures aimed at fall and fracture risk assessment and management.

Hypertension, hypotension and syncope

Hypertension and hypotension are strictly related phenomena, that frequently coexist within the spectrum of cardiovascular autonomic dysfunction, especially at advanced age. Indeed, antihypertensive treatment may predispose to orthostatic and post-prandial hypotension, while intensive blood pressure lowering may be responsible for systemic hypotension. Over recent years, systemic and orthostatic hypotension have emerged as important although often neglected risk factors for adverse outcomes, paralleling the widely recognized arterial hypertension. Both hypertension and hypotension are associated with detrimental effects on target organs and survival, thus significantly impacting patients' prognosis, functional autonomy and quality of life. Balancing low and high blood pressure requires accurate diagnostic assessment of blood pressure values and patients' hypotensive susceptibility, which allow for the development of customized treatment strategies based on individual hypo/hypertensive risk profile. The present review illustrates the complex interrelationship between hypotension and hypertension and discusses the relevant prognostic role of these conditions. Additionally, it provides an overview on hypotension detection and treatment in patients with hypertension, focusing on customized diagnostic and therapeutic strategies.

Risk Factors for Syncope Associated With Multigenerational Relatives With a History of Syncope

IMPORTANCE

Reflex syncope is the major cause of transient loss of consciousness, which affects one-third of the population, but effective treatment for individuals with severe syncope is lacking. Better understanding of reflex syncope predisposition may offer new therapeutic solutions.

OBJECTIVES

To determine the familial risk of syncope in first-, second-, and third-degree relatives of affected individuals and to explore the role of genes and family environment in reflex syncope.

DESIGN, SETTING, AND PARTICIPANTS

In this national population-based family cohort study, the Swedish multigeneration register was linked to 3 Swedish nationwide registers: hospital discharge, outpatient care, and primary care registers for the period from 1997 to 2015. Sibling pairs born to Swedish parents between 1948 and 2005 were included. Linkage was also made to half-siblings and cousins. Data analysis was performed from June to October 2020.

EXPOSURES

Register-based syncope diagnosis among relatives: pairs of twins, siblings, half-siblings, and cousins.

MAIN OUTCOMES AND MEASURES

Odds ratios for syncope were calculated for relatives (twins, siblings, half-siblings, and cousins) of individuals who had syncope compared with relatives of individuals without syncope for reference. Sensitivity analysis excluding families with definite nonreflex syncope diagnosis was performed.

RESULTS

Among the study population of 2 694 442 participants, 1 381 453 (51.3%) were male, and the median (interquartile range) age was 32 (22-43) years. The study population consisted of 24 020 twins, 1 546 108 siblings, 264 244 half-siblings, and 1 044 546 cousins. In total, 61 861 (2.30%) unique individuals were diagnosed with syncope. Sixty-two percent (38 226) of the syncope-positive individuals were female. The odds ratio (OR) for syncope was 2.39 (95% CI, 1.61-3.53) for twins, 1.81 (95% CI, 1.71-1.91) for siblings, 1.28 (95% CI, 1.20-1.37) for half-siblings, and 1.13 (95% CI, 1.10-1.17) for cousins of individuals with syncope. The OR was highest among male twins at 5.03 (95% CI, 2.57-9.85). The proportion of syncope-positive individuals was consistently higher in women vs men, regardless of degree of relationship (twins: 346 [2.88%] vs 193 [1.61%]; siblings: 22 111 [2.92%] vs 13 419 [1.70%], half-siblings: 4148 [3.44%] vs 2425 [1.93%], cousins: 14 498 [2.87%] vs 9246 [1.72%]). Exclusion of nonreflex syncope diagnoses did not change syncope risk in affected families.

CONCLUSIONS AND RELEVANCE

In this Swedish national population-based study, the risk of syncope among relatives of affected individuals was associated with the relationship degree and was strongest in twins and siblings, which suggests that there are genetic components of reflex syncope. Women were more likely to experience syncope independently of family relationship. A better understanding of genetic predisposition to reflex syncope may offer new therapeutic options in severely affected individuals.

Do implantable loop recorders impact the survival of patients with recurrent unexplained syncope?

Aim: This study compares the outcomes of patients who receive an implantable loop recorder (ILR) for unexplained syncope to a control group without the diagnostic device in German claims data. Methods  and materials: Patients with ILR were matched to a control group based on prior syncope events, age, gender and Charlson Comorbidity index (CCI). Survival, syncope hospitalizations, treatment and costs were compared. Results/conclusion: Four hundred and twelve ILR patients were matched with controls, mean age was 68, mean CCI was 2.7, 42% females. ILR patients lived on average 1.2 years longer than patients in the control group. Twenty-five percent of ILR patients received a therapeutic device compared with 5% in the control group. ILRs might help to diagnose and treat patients with positive impact on survival.

Disease network delineates the disease progression profile of cardiovascular diseases

OBJECTIVE

As Electronic Health Records (EHR) data accumulated explosively in recent years, the tremendous amount of patient clinical data provided opportunities to discover real world evidence. In this study, a graphical disease network, named progressive cardiovascular disease network (progCDN), was built to delineate the progression profiles of cardiovascular diseases (CVD).

MATERIALS AND METHODS

The EHR data of 14.3 million patients with CVD diagnoses were collected for building disease network and further analysis. We applied a new designed method, progression rates (PR), to calculate the progression relationship among different diagnoses. Based on the disease network outcome, 23 disease progression pair were selected to screen for salient features.

RESULTS

The network depicted the dominant diseases in CVD development, such as the heart failure and coronary arteriosclerosis. Novel progression relationships were also discovered, such as the progression path from long QT syndrome to major depression. In addition, three age-group progCDNs identified a series of age-associated disease progression paths and important successor diseases with age bias. Furthermore, a list of important features with sufficient abundance and high correlation was extracted for building disease risk models.

DISCUSSION

The PR method designed for identifying the progression relationship could be widely applied in any EHR database due to its flexibility and robust functionality. Meanwhile, researchers could use the progCDN network to validate or explore novel disease relationships in real world data.

CONCLUSION

The first-time interrogation of such a huge CVD patients cohort enabled us to explore the general and age-specific disease progression patterns in CVD development.

The Impact of a Nurse-Led Syncope Clinic: Experience from a single UK tertiary center

Background

Syncope is a leading cause of hospital admission and is associated with significant morbidity and mortality. Our Syncope Clinic commenced in 2014 and we sought to evaluate its impact on outcomes (1‐yr mortality and syncope re‐hospitalization) in patients discharged following syncope admission.

Methods

A single‐center study of all consecutive patients discharged with syncope (ICD‐10 R55) between April 2012 and 2017. Patient demographics, comorbidities, hospital stay, syncope re‐hospitalization, and mortality at one‐year were collected. Those subsequently referred and seen in Syncope Clinic were compared with those who were not and predictors of poor outcome were evaluated.

Results

In total 2950 patients were discharged from hospital with syncope (median age: 73years, 51% male) with 1220 (41%) discharged same‐day; after commencement of Syncope Clinic 231were subsequently reviewed here. Overall mortality was 11%, which was lower in the Syncope Clinic group (3% vs 12%, P < .001). Temporal analysis revealed reduced re‐hospitalization following commencement of Syncope Clinic (2% vs 6%, P = .027). Independent predictors of mortality were increasing age (HR 1.03, 95% CI 1.03‐1.04), AF (HR 1.6, 95% CI 1.2‐2.1), HF (HR 2.2, 95% CI 1.6‐3.0), COPD (HR 1.9, 95% CI 1.4‐2.7), and CHADS₂ score ≥ 1 (HR 1.45, 95% CI 1,12‐1.87). Syncope Clinic attendance was associated with reduced mortality (HR 0.3, 95% CI 0.1‐0.6).

Conclusions

Syncope patients discharged from hospital had reduced 1yr mortality if seen in subsequent Syncope Clinic. Independent predictors of mortality were COPD, HF, AF, and CHADS₂ ≥1. Prospective randomized trials of Syncope Clinics are warranted.

Burden of recurrent syncope and injuries and the usefulness of implantable cardiac monitors: insights from a nationwide longitudinal cohort analysis

Aim: The study assesses the burden and costs of recurring unexplained syncope and injuries and the effectiveness of implantable loop recorders. Methods: The English national hospital database (Hospital Episode Statistics) was retrospectively analyzed. Results: 12,002 patients were identified with repeated syncope hospitalizations. 25% of patients were hospitalized at least once again for syncope, 9% of the patients were hospitalized at least once for an injury, causing substantial costs. In the second analysis: 10,902 patients implanted with an implantable cardiac monitor were tracked. By year 3, hospitalizations due to syncope had dropped by 60% versus pre-implantable cardiac monitor (ICM) levels. Conclusion: This study shows a high rate of recurrent syncope admissions and a parallel burden of hospitalizations for injuries. Use of an ICM appears to reduce syncope hospitalizations.

Orthostatic hypotension is associated with new-onset atrial fibrillation: Systemic review and meta-analysis

Introduction

Orthostatic hypotension (OH) is common among elderly patients. Its presence may herald severe underlying comorbidities and be associated with a higher risk of mortality. Interestingly, recent studies suggest that OH is associated with new-onset atrial fibrillation (AF). However, a systematic review and meta-analysis of the literature has not been performed. We assessed the association between AF and OH through a systematic review of the literature and a meta-analysis.

Methods

We comprehensively searched the databases of MEDLINE and EMBASE from inception to November 2018. Published prospective or retrospective cohort studies that compared new-onset AF between male patients with and without OH were included. Data from each study were combined using the random-effects, generic inverse-variance method of DerSimonian and Laird to calculate risk ratios and 95% confidence intervals.

Results

Four studies from October 2010 to March 2018 were included in the meta-analysis involving 76,963 subjects (of which 3318 were diagnosed with OH). The presence of OH was associated with new-onset AF (pooled risk ratio 1.48; 95% confidence interval [1.21, 1.81], p?< 0.001; I2 = 69.4%). In hypertensive patients, analysis revealed an association between OH and the occurrence of new-onset AF (OR 1.46; 95% CI [1.27, 1.68], p < 0.001 with I2 = 0).

Conclusions

OH was associated with new-onset AF up to 1.5-fold compared with those subjects without OH. The interplay between OH and AF is likely bidirectional.

Orthostatic hypotension and the risk of atrial fibrillation and other cardiovascular diseases: An updated meta-analysis of prospective cohort studies

The relationships between orthostatic hypotension (OH) and some kinds of cardiovascular disease are inconsistent among studies. This updated meta-analysis was conducted in hopes of producing progress on this topic. A systematic database search was performed in electronic databases, including the Chinese Biomedical Database (CBM), PubMed, Web of Science, and the Cochrane Library. Summary hazard ratio (HR) estimates with 95% confidence intervals (CIs) were calculated by a random-effects model. Statistical heterogeneity was assessed with Cochran's Q test and the I2 statistic. From 1462 potentially eligible records, 15 studies met the inclusion criteria. Subjects with OH had a high risk of heart failure (HF) and atrial fibrillation (AF) (pooled HR 1.34, 95% CI 1.17-1.52, P < 0.001 and pooled HR 1.51, 95% CI 1.28-1.79, P < 0.001, respectively). This meta-analysis also showed significant associations between OH and the risks of developing coronary heart disease (CHD) (pooled HR 1.44, 95% CI 1.18-1.75, P < 0.001) and myocardial infarction (MI) (pooled HR 1.52, 95% CI 1.12-2.06, P = 0.008). Our study suggests that OH is positively associated with high risks of HF and AF. Moreover, it may be related to high risks of CHD and MI.

Orthostatic hypotension in internal medicine wards

OBJECTIVES

Most studies of orthostatic hypotension (OH) have focused on community-dwelling and institutionalized patient populations. Less is known about OH in hospitalized patients. Moreover, a comprehensive review of OH in internal medicine wards has not been published in the English literature. Our purpose is to provide current information regarding OH in internal medicine inpatients.

METHODS

A comprehensive search of medical databases was performed for potentially relevant articles, using the following keywords: postural or orthostatic hypotension, with the combination of hospitalization or internal medicine. Inclusion criteria were: population of patients hospitalized for acute disorders in internal medicine or geriatric wards with a sample size of ≥50 and publication as an original full-length article in the English language. Data from 14 selected studies are reviewed, including: pathophysiology, evaluation, prevalence, manifestations, risk factors, prognosis, and management.

RESULTS

OH is a common and often symptomatic disorder in elderly internal medicine patients. The prevalence of OH in this population ranges from 22-75%. There are substantial discrepancies between the studies reviewed regarding definitions and means of evaluating OH. OH in internal medicine wards is largely non-neurogenic and multifactorial. The main predisposing factors for OH are prolonged bed rest, hypertension, and heart failure. OH in internal medicine wards is managed mainly with non-pharmacologic interventions, and is frequently reversible.

CONCLUSIONS

In internal medicine inpatients, OH warrants attention because this disorder is common, potentially dangerous, and treatable. In the hospital setting, OH should be routinely assessed on ambulation, following the current guidelines for OH definition and meaning.

Pacing therapy in the management of unexplained syncope: a tertiary care centre prospective study

Objective

Pacemaker (PM) therapy is effective when syncope is associated with bradycardia, but syncope recurrences and fall injuries after PM implantation may occur. We aimed to survey indications and outcomes of PM implantation, following evaluation of unexplained syncope.

Methods

Among 1666 consecutive unpaced patients investigated in a tertiary syncope unit by carotid-sinus massage (CSM), head-up tilt test (HUT) and ECG monitoring, 106 (6.4%; age, 65 ± 17 years) received a PM. We assessed bradycardia detection methods, PM implantation indications, and explored incidence of recurrent syncope, fall-related fractures and mortality.

Results

Indications for PM therapy were met in 32/106 patients (30%) by CSM, in 41/106 (39%) by HUT, in 14/106 patients (13%) by implantable loop-recorder (ILR) and in 19/106 (18%) by standard ECG. Sinus arrest with asystole was the predominant PM indication during CSM/HUT and external ECG monitoring, whereas ILR detected proportionally the same numbers o f asystole due to sinus arrest and atrioventricular block. During follow-up (median, 4.3 years), 15 patients (14%) had syncope recurrence, 15 suffered fall-related fractures and 9 died. Neither syncope recurrence nor fall-related fractures were dependent on initial PM indication. The composite endpoint of recurrent syncope/fall-related fracture was associated with treated hypertension (OR 2.45; 95% CI 1.00 to 6.0), reduced glomerular filtration rate (OR 1.63 per 10 mL/min↓; 95% CI 1.22 to 2.19) and atrial fibrillation (OR 3.98; 95% CI 1.11 to 14.3). Recurrent syncope predicted increased mortality (OR 9.20; 95% CI 1.89 to 44.8).

Conclusions

Cardiovascular autonomic testing and ECG monitoring effectively identify pacing indications in patients with unexplained syncope. After PM implantation, treated hypertension, renal failure and atrial fibrillation predict syncope recurrence and fall-related injury. Recurrent syncope predicts increased mortality.

Orthostatic hypotension and physical functioning in older adults: A systematic review and meta-analysis

BACKGROUND

Orthostatic hypotension (OH) may negatively affect physical functioning and aggravate morbidities, but existing evidence is contradictory.

METHODS

MEDLINE (from 1946), PubMed (from 1966) and EMBASE databases (from 1947) were systematically searched for studies on the association of OH and physical functioning in older adults, categorized as: balance, gait characteristics, walking speed, Timed Up and Go time, handgrip strength (HGS), physical frailty, exercise tolerance, physical activity, activities of daily living (ADL), and performance on the Hoehn and Yahr scale (HY) and Unified Parkinson's Disease Rating Scale (UPDRS). Study quality was assessed using the Newcastle Ottawa Scale.

RESULTS

Forty-two studies were included in the systematic review (29,421 individuals) and 29 studies in the meta-analyses (23,879 individuals). Sixteen out of 42 studies reported a significant association of OH with worse physical functioning. Meta-analysis showed a significant association of OH with impaired balance, ADL performance and HY/UPDRS III performance, but not with gait characteristics, mobility, walking speed, TUG, HGS, physical frailty, exercise tolerance, physical activity and UPDRS II performance.

CONCLUSIONS

OH was associated with impaired balance, ADL performance and HY/UPDRS III performance, but not with other physical functioning categories. The results suggest that OH interventions could potentially improve some aspects of physical functioning.

Prognostic significance of noncardiac syncope in the general population: A systematic review and meta-analysis

INTRODUCTION

Cardiac syncope heralds significantly higher mortality compared with syncope due to noncardiac causes or unknown etiology, commonly considered a benign event. A few epidemiologic studies have examined the outcome of noncardiac/unexplained syncope comparing individuals with and without syncope, but with controversial results. We performed a systematic review and meta-analysis to clarify whether history of noncardiac/unexplained syncope is associated with increased all-cause mortality in the general population.

METHODS AND RESULTS

Our systematic review of the literature published between January 1, 1966, and March 31, 2018 sought prospective, observational, cohort studies reporting summary-level outcome data about all-cause mortality in subjects with history of noncardiac/unexplained syncope compared with syncope-free participants. Adjusted hazard ratios were pooled through inverse variance random-effect meta-analysis to compute the summary effect size. Meta-regression models were performed to explore the effect of age, cardiovascular risk factors, or other potential confounders on the measured effect size. We identified four studies including 287 382 individuals (51.6% men; age, 64 ± 12 years): 38 843 with history of noncardiac/unexplained syncope and 248 539 without history of syncope. The average follow-up was 4.4 years. History of noncardiac/unexplained syncope was associated with higher all-cause mortality (pooled adjusted hazard ratio = 1.13; 95% confidence interval, 1.05 to 1.23). Meta-regression analysis showed a stronger positive relationship proportional to aging and increasing prevalence of diabetes and hypertension.

CONCLUSIONS

This study-level meta-analysis showed that among older, diabetic and/or hypertensive individuals, history of noncardiac/unexplained syncope, even in the absence of an obvious cardiac etiology, is associated with higher all-cause mortality.