Out-of-hospital cardiac arrest in patients with psychiatric disorders — Characteristics and outcomes

Long-term outcomes among out-of-hospital cardiac arrest survivors with reversible vs. non-reversible causes

AIMS

A reversible cause of out-of-hospital cardiac arrest (OHCA) is vaguely defined in international guidelines as an identifiable transient or potentially correctable condition. However, studies evaluating long-term outcomes of patients experiencing OHCA due to reversible and non-reversible causes are lacking. We aimed to determine differences in long-term outcomes in OHCA survivors according to different aetiology.

METHODS AND RESULTS

From the British Columbia Cardiac Arrest registry, adults with non-traumatic OHCA (2009-2016) surviving to hospital discharge were identified. Patients were categorized by OHCA aetiology combining reversibility and underlying ischaemic aetiology. The primary outcome was a composite of all-cause mortality, recurrent OHCA, or re-hospitalization for sudden cardiac arrest or ventricular arrhythmias. Using the Kaplan-Meier method and multivariable Cox regression models, we compared the risk of the composite outcome according to different OHCA aetiology. Of 1325 OHCA hospital-discharge survivors (median age 62.8 years, 77.9% male), 431 (32.5%) had reversible ischaemic, 415 (31.3%), non-reversible ischaemic, 99 (7.5%), reversible non-ischaemic, and 380 (28.7%), non-reversible non-ischaemic aetiologies. At 3 years post discharge, the Kaplan-Meier event-free rate was highest in patients with a reversible ischaemic aetiology [91%, 95% confidence interval (CI) 87-94%], and lowest in those with a reversible non-ischaemic aetiology (62%, 95% CI 51-72%). In multivariate analyses, compared with non-reversible non-ischaemic cause, reversible ischaemic cause was associated with a significantly lower hazard ratio (HR; 0.52, 95% CI 0.33-0.81), reversible non-ischaemic cause with a significantly higher HR (1.53, 95% CI 1.03-2.32), and non-reversible ischaemic cause with a non-significant HR (0.92, 95% CI 0.64-1.33) for the composite outcome.

CONCLUSION

Compared to other aetiologies, the presence of a reversible ischaemic cause is associated with improved long-term OHCA outcomes.

Nationwide burden of sudden cardiac death among patients with a psychiatric disorder

BACKGROUND

Patients with psychiatric disorders have increased all-cause mortality compared with the general population. Previous research has shown that there is a fourfold increased risk of sudden cardiac death (SCD) among the young.

OBJECTIVE

To investigate the incidence of SCD in patients with psychiatric disorders aged 18-90 years in the Danish population by systematically reviewing all deaths in 1 year.

METHODS

We examined all deaths in Denmark among residents aged 18-90 years in 2010 by reviewing death certificates and autopsy reports. All deaths were categorised as non-SCD or SCD based on the available information. Psychiatric disorder was defined according to International Classification of Diseases, 10th revision criteria or by redemption of a prescription for psychotropic medication within 1 year.

RESULTS

Of 4.3 million residents in 2010, we observed 45 703 deaths, of which 6002 were due to SCD. Overall, the incidence rate ratio of SCD was 1.79-6.45 times higher among patients with psychiatric disorders than in the general population and was age dependent (p<0.001 across all age groups). When adjusting for age, sex and comorbidities, psychiatric disorders were independently associated with SCD, with a HR of 2.31 (2.19 to 2.43, p<0.001), and HR was highest among patients with schizophrenic disorders, with a HR of 4.51 (3.95 to 5.16, p <0.001). Furthermore, 18-year-old patients with a psychiatric disorder had an expected 10-year excess loss of life. Patients aged 18-40 with a psychiatric disorder had 13% of excess life years lost caused by SCD.

CONCLUSION

In this study, the rate of SCD in patients with psychiatric disorders is higher across all age groups than in the general population. Having a psychiatric disorder is independently associated with SCD. Patients with schizophrenic disease had the highest rates of SCD. Life expectancy for an 18-year old with a psychiatric disorder is estimated to be 10 years shorter in comparison with those without this disorder.

The association of depression and patient and resuscitation characteristics with survival after out-of-hospital cardiac arrest: a cohort study

AIMS

Out-of-hospital cardiac arrest (OHCA) is a leading cause of death worldwide, with cardiovascular disease (CVD) being a key risk factor. This study aims to investigate disparities in patient/OHCA characteristics and survival after OHCA among patients with vs. without depression.

METHODS AND RESULTS

This is a retrospective cohort study using data from the AmsteRdam REsuscitation Studies (ARREST) registry from 2008 to 2018. History of comorbidities, including depression, was obtained from the patient's general practitioner. Out-of-hospital cardiac arrest survival was defined as survival at 30 days post-OHCA or hospital discharge. Logistic regression models were used to obtain crude and adjusted odds ratios (ORs) for the association between depression and OHCA survival and possible effect modification by age, sex, and comorbidities. The potential mediating effects of initial heart rhythm and provision of bystander cardiopulmonary resuscitation were explored. Among 5594 OHCA cases, 582 individuals had pre-existing depression. Patients with depression had less favourable patient and OHCA characteristics and lower odds of survival after adjustment for age, sex, and comorbidities [OR 0.65, 95% confidence interval (CI) 0.51-0.82], with similar findings by sex and age groups. The association remained significant among the Utstein comparator group (OR 0.63, 95% CI 0.45-0.89) and patients with return of spontaneous circulation (OR 0.60, 95% CI 0.42-0.85). Initial rhythm and bystander cardiopulmonary resuscitation partially mediated the observed association (by 27 and 7%, respectively).

CONCLUSION

Out-of-hospital cardiac arrest patients with depression presented more frequently with unfavourable patient and OHCA characteristics and had reduced chances of survival. Further investigation into potential pathways is warranted.

Clinical Trajectories and Long-Term Outcomes of Alcoholic Versus Other Forms of Dilated Cardiomyopathy

BACKGROUND

Alcoholic cardiomyopathy (ACM) is a form of dilated cardiomyopathy (DCM) occurring secondary to long-standing heavy alcohol use and is associated with poor outcomes, but the cause-specific risks are insufficiently understood.

METHOD

Between 1997 and 2018, we identified all patients with a first diagnosis of ACM or DCM. The cumulative incidence of different causes of hospitalisation and mortality in the two groups was calculated using the Fine-Gray and Kaplan-Meier methods.

RESULTS

A Total of 1,237 patients with ACM (mean age 56.3±10.1 years, 89% men) and 17,211 individuals with DCM (mean age 63.6±13.8 years, 71% men) were identified. Diabetes (10% vs 15%), hypertension (22% vs 31%), and stroke (8% vs 10%) were less common in ACM than DCM, whereas obstructive lung disease (15% vs 12%) and liver disease (17% vs 2%) were more prevalent (p<0.05). Cumulative 5-year mortality was 49% in ACM vs 33% in DCM, p<0.0001, multivariable adjusted hazards ratio 2.11 (95% confidence interval 1.97-2.26). The distribution of causes of death was similar in ACM and DCM, with the predominance of cardiovascular causes in both groups (42% in ACM vs 44% in DCM). 5-year cumulative incidence of heart failure hospitalisations (48% vs 54%) and any somatic cause (59% vs 65%) were also similar in ACM vs DCM. At 1 year, the use of beta blockers (55% vs 80%) and implantable cardioverter defibrillators (3% vs 14%) were significantly less often used in ACM vs DCM.

CONCLUSIONS

Patients with ACM had similar cardiovascular risks and hospitalisation patterns as other forms of DCM, but lower use of guideline-directed cardiovascular therapies and greater mortality.

Management of dyslipidaemia in individuals with severe mental illness: a population-based study in the Greater Copenhagen Area

Background

Severe mental illness (SMI) is associated with increased cardiovascular risk. Dyslipidaemia is a potentially modifiable risk factor, which may be inadequately managed in patients with SMI.

Objectives

To assess management of dyslipidaemia in patients with SMI versus healthy controls (HCs) in 2005 and 2015.

Design and methods

Using Danish registers, we identified adult patients with SMI in the Greater Copenhagen Area (schizophrenia spectrum disorders or bipolar disorder) with ⩾1 general practitioner contact in the year before 2005 and 2015, respectively, and HCs without SMI matched on age and gender (1:5). Outcomes were lipid-profile measurements, presence of dyslipidaemia and redemption of lipid-lowering pharmacotherapy. Differences in outcomes between patients with SMI and controls were measured with multivariable logistic regression.

Results

We identified 7217 patients with SMI in 2005 and 9939 in 2015. After 10 years, patients went from having lower odds of lipid measurements to having higher odds of lipid measurements compared with HCs [odds ratio (OR)2005 0.70 (99% confidence interval (CI) 0.63-0.78) versus OR2015 1.34 (99% CI 1.24-1.44); p2005versus2015 < 0.01]. Patients had higher odds of dyslipidaemia during both years [OR2005 1.43 (99% CI 1.10-1.85) and OR2015 1.23 (99% CI 1.08-1.41)]. Patients went from having lower odds of receiving lipid-lowering pharmacotherapy to having higher odds of receiving lipid-lowering pharmacotherapy [OR2005 0.77 (99% CI 0.66-0.89) versus OR2015 1.37 (99% CI 1.24-1.51); p2005versus2015 < 0.01]. However, among persons at high cardiovascular risk, patients had lower odds of receiving lipid-lowering pharmacotherapy during both years, including subsets with previous acute coronary syndrome [OR2005 0.30 (99% CI 0.15-0.59) and OR2015 0.44 (99% CI 0.24-0.83)] and ischaemic stroke or transient ischaemic attack (TIA) [OR2005 0.43 (99% CI 0.26-0.69) and OR 2015 0.61 (99% CI 0.41-0.89)].

Conclusion

These results imply an increased general awareness of managing dyslipidaemia among patients with SMI in the primary prophylaxis of cardiovascular disease. However, secondary prevention with lipid-lowering drugs in patients with SMI at high cardiovascular risk may be lacking.

Outcomes of out-of-hospital cardiac arrest in adult congenital heart disease: a Danish nationwide study

AIMS

The risk, characteristics, and outcome of out-of-hospital cardiac arrest (OHCA) in patients with congenital heart disease (CHD) remain scarcely investigated.

METHODS AND RESULTS

An epidemiological registry-based study was conducted. Using time-dependent Cox regression models fitted with a nested case-control design, hazard ratios (HRs) with 95% confidence intervals of OHCA of presumed cardiac cause (2001-19) associated with simple, moderate, and severe CHD were calculated. Moreover, using multiple logistic regression, we investigated the association between pre-hospital OHCA characteristics and 30-day survival and compared 30-day survival in OHCA patients with and without CHD. Overall, 43 967 cases (105 with simple, 144 with moderate, and 53 with severe CHD) and 219 772 controls (median age 72 years, 68.2% male) were identified. Any type of CHD was found to be associated with higher rates of OHCA compared with the background population [simple CHD: HR 1.37 (1.08-1.70); moderate CHD: HR 1.64 (1.36-1.99); and severe CHD: HR 4.36 (3.01-6.30)]. Pre-hospital cardiopulmonary resuscitation and defibrillation were both associated with improved 30-day survival in patients with CHD, regardless of CHD severity. Among patients with OHCA, simple, moderate, and severe CHD had a similar likelihood of 30-day survival compared with no CHD [odds ratio 0.95 (0.53-1.69), 0.70 (0.43-1.14), and 0.68 (0.33-1.57), respectively].

CONCLUSION

A higher risk of OHCA was found throughout the spectrum of CHD. Patients with and without CHD showed the same 30-day survival, which relies on the pre-hospital chain of survival, namely cardiopulmonary resuscitation and defibrillation.

Long-term stress conditions and out-of-hospital cardiac arrest risk: a nested case-control study

OBJECTIVE

Patients with stress-related disorders and anxiety are at increased risk of developing cardiovascular disease. However, the risk of out-of-hospital cardiac arrest (OHCA) is scarcely investigated. We aimed to establish whether long-term stress (post-traumatic stress disorder, adjustment disorder) or anxiety is associated with OHCA in the general population.

METHODS

We conducted a nested case-control study in a nationwide cohort of individuals between 1 June 2001 and 31 December 2015 in Denmark. Cases were OHCA patients with presumed cardiac causes. Each case was matched by age, sex and date of OHCA with 10 non-OHCA controls from the general population. HRs for OHCA were derived from Cox models after controlling for common OHCA risk factors. Stratified analyses were performed according to sex, age and pre-existing cardiovascular disease.

RESULTS

We included 35 195 OHCAs and 351 950 matched controls (median age 72 years; 66.8% male). Long-term stress conditions were diagnosed in 324 (0.92%) OHCA cases and 1577 (0.45%) non-OHCA controls, and were associated with higher rate of OHCA (HR 1.44, 95% CI 1.27 to 1.64). Anxiety was diagnosed in 299 (0.85%) OHCA cases and 1298 (0.37%) controls, and was associated with increased rate of OHCA (HR 1.56, 95% CI1.37 to 1.79). We found no interaction with sex, age or history of cardiovascular diseases.

CONCLUSION

Patients with stress-related disorders or anxiety have an increased rate of OHCA. This association applies equally to men and women and is independent from the presence of cardiovascular disease. Awareness of the higher risks of OHCA in patients with stress-related disorders and anxiety is important when treating these patients.

Use of healthcare services before and after out-of-hospital cardiac arrest

INTRODUCTION

Knowledge about the use of healthcare services in patients experiencing out-of-hospital cardiac arrest (OHCA) is limited. We aimed to describe and compare the use of healthcare by OHCA survivors two years before and one year after cardiac arrest.

METHODS

Adult patients with OHCA of medical cause, who survived >30 days, were identified in the Norwegian Cardiac Arrest Registry. The Norwegian Patient Registry, The Cause of Death Registry, and The Norwegian Registry for Primary Healthcare provided data on survival and the use of healthcare services. We investigated the use of primary, specialist and mental healthcare, as well as rehabilitation services.

RESULTS

In 2015-2018, 13,112 OHCA cases were identified; 1435 (14%) patients survived >30 days (6.8/100,000 patients/year). The proportion of patients in the cohort that used primary healthcare each month increased form 43% before to 69% after OHCAto (p<0.001). We found a doubling of monthly healthcare contacts in both specialist healthcare (from 26% to 57%, p<0.001) and mental healthcare (from 3% to 8%, p>0.001). The observed increases in primary, specialist and mental healthcare use started two weeks, six months, and eight months before OHCA, respectively. Half of the patients had contact with primary healthcare services on the same day as the cardiac arrest. Two out of five patients were registered for rehabilitation after OHCA.

CONCLUSION

The use of primary, specialist and mental healthcare services increased before OHCA and remained significantly higher the year after OHCA. Less than half of the patients surviving cardiac arrest were registered for rehabilitation.

Registered prodromal symptoms of out-of-hospital cardiac arrest among patients calling the medical helpline services

Background Early identification of warning symptoms among out-of-hospital cardiac arrest (OHCA) patients remains challenging. Thus, we examined the registered prodromal symptoms of patients who called medical helpline services within 30-days before OHCA. Methods Patients unwitnessed by emergency medical services (EMS) aged ≥18 years during their OHCA were identified from the Danish Cardiac Arrest Registry (2014-2018) and linked to phone records from the 24-h emergency helpline (1-1-2) and out-of-hours medical helpline (1813-Medical Helpline) in Copenhagen before the arrest. The registered symptoms were categorized into chest pain; breathing problems; central nervous system (CNS)-related/unconsciousness; abdominal/back/urinary; psychiatric/addiction; infection/fever; trauma/exposure; and unspecified (diverse from the beforementioned categories). Analyses were divided by the time-period of calls (0-7 days/8-30 days preceding OHCA) and call type (1-1-2/1813-Medical Helpline). Results Of all OHCA patients, 18% (974/5442) called helpline services (males 56%, median age 76 years[Q1-Q3:65-84]). Among these, 816 had 1145 calls with registered symptoms. The most common symptom categories (except for unspecified, 33%) were breathing problems (17%), trauma/exposure (17%), CNS/unconsciousness (15%), abdominal/back/urinary (12%), and chest pain (9%). Most patients (61%) called 1813-Medical Helpline, especially for abdominal/back/urinary (17%). Patients calling 1-1-2 had breathing problems (24%) and CNS/unconsciousness (23%). Nearly half of the patients called within 7 days before their OHCA, and CNS/unconsciousness (19%) was the most registered. The unspecified category remained the most common during both time periods (32%;33%) and call type (24%;39%). Conclusions Among patients who called medical helplines services up to 30-days before their OHCA, besides symptoms being highly varied (unspecified (33%)), breathing problems (17%) were the most registered symptom-specific category.

Sudden cardiac arrest in patients with schizophrenia: A population-based study of resuscitation outcomes and pre-existing cardiovascular disease

Objective

Individuals with schizophrenia carry a high burden of cardiovascular disease and elevated rates of sudden cardiac arrest (SCA), but little published data is available regarding survival from SCA in this population. The authors compared cardiovascular disease burden and resuscitation outcomes following SCA in individuals with and without schizophrenia.

Methods

Case-control analysis drawn from a prospective community-based study of SCA in a large community. The authors defined cases as having a pre-SCA history of schizophrenia, and controls as individuals with SCA without a history of schizophrenia. SCA cases with schizophrenia were compared to a 1:5 age- and sex-frequency-matched sample of SCA cases without schizophrenia.

Results

The 103 SCA schizophrenia cases were as likely as the 515 cases without schizophrenia to have resuscitation attempted (75% vs. 80%; p = 0.24) and had a shorter 911 call mean response time (5.8 min vs. 6.9 min, p < 0.001). However, they were significantly less likely to present with a shockable rhythm (ventricular fibrillation/pulseless ventricular tachycardia 16% vs. 43%, p < 0.001), and less likely to survive to hospital discharge (3% vs. 14%, p = 0.008). Pre-arrest cardiovascular disease burden was similar in patients with and without schizophrenia.

Conclusions

Despite comparable resuscitation characteristics and cardiovascular disease burden, patients with schizophrenia had significantly lower rates of SCA survival. The paucity of previous research into this phenomenon warrants further investigation to identify factors that may improve survival.

Incidence, characteristics and outcomes of out-of-hospital cardiac arrests in patients with psychiatric illness: A systematic review

Aim

To conduct a systematic literature review of the existing evidence on incidence, characteristics and outcomes after out-of-hospital cardiac arrest (OHCA) in patients with psychiatric illness.

Methods

We searched Embase, Medline, PsycINFO and Web of Science using a comprehensive electronic search strategy to identify observational studies reporting on OHCA incidence, characteristics or outcomes by psychiatric illness status. One reviewer screened all titles and abstracts, and a second reviewer screened a random 10%. Two reviewers independently performed data extraction and quality assessment.

Results

Our search retrieved 11,380 studies, 10 of which met our inclusion criteria (8 retrospective cohort studies and two nested case-control studies). Three studies focused on depression, whilst seven included various psychiatric conditions. Among patients with an OHCA, those with psychiatric illness (compared to those without) were more likely to have: an arrest in a private location; an unwitnessed arrest; more comorbidities; less bystander cardiopulmonary resuscitation; and an initial non-shockable rhythm. Two studies reported on OHCA incidence proportion and two reported on survival, showing higher risk, but lower survival, in patients with psychiatric illness.

Conclusion

Psychiatric illness in relation to OHCA incidence and outcomes has rarely been studied and only a handful of studies have reported on OHCA characteristics, highlighting the need for further research in this area. The scant existing literature suggests that psychiatric illness may be associated with higher risks of OHCA, unfavourable characteristics and poorer survival. Future studies should further investigate these links and the role of potential contributory factors such as socioeconomic status and comorbidities.

Emergency Medical Services response levels and subsequent emergency contacts among patients with a history of mental illness in Denmark: a nationwide study

BACKGROUND AND IMPORTANCE

People with mental illness have higher use of emergency services than the general population and may experience problems with navigating in complex healthcare systems. Poor physical health contributes to the excess mortality among the mentally ill.

OBJECTIVE

To compare the level of Emergency Medical Services (EMS) response and subsequent contacts emergency between patients with and without a history of mental illness.

DESIGN, SETTING, AND PARTICIPANTS

A nationwide cohort study was conducted in Denmark including medical 1-1-2 calls 2016 2017. The healthcare system is financed through taxation allowing free access to healthcare services including ambulance services.

EXPOSURE

Exposed groups had a history of major, moderate, or minor mental illness.

OUTCOME MEASURES AND ANALYSIS

We studied seven national prehospital care Performance Indicators (PI 1-7). The selected PI concerned EMS response levels and subsequent contacts to prehospital and in-hospital services. Exposed groups were compared to nonexposed groups using regression analyses.

RESULTS

We included 492 388 medical 1-1-2 calls: 8, 10, and 18% of calls concerned patients with a history of major, moderate, or minor mental illness, respectively.There were no clinically relevant differences regarding response times (PI 1-2) or registration of symptoms (PI 3) between groups.If only telephone advice was offered, patients with a history of major, moderate or minor mental illness were more likely to recall within 24 h (PI 4): adjusted risk ratio (RR) 2.11 (1.88-2.40), 1.96 (1.20-2.21), and 1.38 (1.20-1.60), but less or equally likely to have an unplanned hospital contact within 7 days (PI 6): adjusted RRs 1.05 (0.99-1.12), 1.04 (0.99-1.10), and 0.90 (0.85-0.94), respectively.If released at the scene, the risk of recalling (PI 5) or having an unplanned hospital contact (PI 7) was higher among patients with a history of mental illness: adjusted RRs 2.86 (2.44-3.36), 2.41 (2.05-2.83), and 1.57 (1.35-1.84), and adjusted RRs 2.10 (1.94-2.28), 1.68 (1.55-1.81), and 1.25 (1.17-1.33), respectively.Patients with a history of mental illness were more likely to receive telephone advice only adjusted RRs 1.61 (1.53-1.70), 1.30 (1.24-1.37), and 1.08 (1.04-1.13), and being released at scene adjusted RRs 1.11 (1.08-1.13), 1.03 (1.01-1.04), and 1.05 (1.03-1.07).

CONCLUSION

More than one-third of the study population had a history of mental illness. These patients received a significantly lighter EMS response than patients with no history of mental illness. They were significantly more likely to use the emergency care system again if released at scene. This risk increased with the increasing severity of the mental illness.

Risk of out-of-hospital cardiac arrest in patients with bipolar disorder or schizophrenia

OBJECTIVE

Patients with bipolar disorder and schizophrenia are at high cardiovascular risk; yet, the risk of out-of-hospital cardiac arrest (OHCA) compared with the general population remains scarcely investigated.

METHODS

We conducted a nested case-control study using Cox regression to assess the association of bipolar disorder and schizophrenia with the HRs of OHCA of presumed cardiac cause (2001-2015). Reported are the HRs with 95% CIs overall and in subgroups defined by established cardiac disease, cardiovascular risk factors and psychotropic drugs.

RESULTS

We included 35 017 OHCA cases and 175 085 age-matched and sex-matched controls (median age 72 years and 66.9% male). Patients with bipolar disorder or schizophrenia had overall higher rates of OHCA compared with the general population: HR 2.74 (95% CI 2.41 to 3.13) and 4.49 (95% CI 4.00 to 5.10), respectively. The association persisted in patients with both cardiac disease and cardiovascular risk factors at baseline (bipolar disorder HR 2.14 (95% CI 1.72 to 2.66), schizophrenia 2.84 (95% CI 2.20 to 3.67)) and among patients without known risk factors (bipolar disorder HR 2.14 (95% CI 1.09 to 4.21), schizophrenia HR 5.16 (95% CI 3.17 to 8.39)). The results were confirmed in subanalyses only including OHCAs presenting with shockable rhythm or receiving an autopsy. Antipsychotics-but not antidepressants, lithium or antiepileptics (the last two only tested in bipolar disorder)-increased OHCA hazard compared with no use in both disorders.

CONCLUSIONS

Patients with bipolar disorder or schizophrenia have a higher rate of OHCA compared with the general population. Cardiac disease, cardiovascular risk factors and antipsychotics represent important underlying mechanisms.