Estimated incidence and risk factors of sudden unexpected death

Fine particulate matter-sudden death association modified by ventricular hypertrophy and inflammation: a case-crossover study

Background

Sudden death accounts for approximately 10% of deaths among working-age adults and is associated with poor air quality. Objectives: To identify high-risk groups and potential modifiers and mediators of risk, we explored previously established associations between fine particulate matter (PM2.5) and sudden death stratified by potential risk factors.

Methods

Sudden death victims in Wake County, NC, from 1 March 2013 to 28 February 2015 were identified by screening Emergency Medical Systems reports and adjudicated (n = 399). Daily PM2.5 concentrations for Wake County from the Air Quality Data Mart were linked to event and control periods. Potential modifiers included greenspace metrics, clinical conditions, left ventricular hypertrophy (LVH), and neutrophil-to-lymphocyte ratio (NLR). Using a case-crossover design, conditional logistic regression estimated the OR (95%CI) for sudden death for a 5 μg/m3 increase in PM2.5 with a 1-day lag, adjusted for temperature and humidity, across risk factor strata.

Results

Individuals having LVH or an NLR above 2.5 had PM2.5 associations of greater magnitude than those without [with LVH OR: 1.90 (1.04, 3.50); NLR > 2.5: 1.25 (0.89, 1.76)]. PM2.5 was generally less impactful for individuals living in areas with higher levels of greenspace.

Conclusion

LVH and inflammation may be the final step in the causal pathway whereby poor air quality and traditional risk factors trigger arrhythmia or myocardial ischemia and sudden death. The combination of statistical evidence with clinical knowledge can inform medical providers of underlying risks for their patients generally, while our findings here may help guide interventions to mitigate the incidence of sudden death.

Sickle Cell Disease Related Vasculopathies and Early Evaluation in a Pediatric Population

BACKGROUND/AIM

Cardiovascular pathologies are ubiquitous in sickle cell disease (SCD). A targeted literature review was conducted to compare the overall epidemiology of selected vasculopathies seen in SCD (SCDVs) compared to the general population. Since many SCDV may originate in childhood, the study also focused on the retrospective investigation of SCDVs in a pediatric cohort at the Harbor-UCLA Medical Center.

PATIENTS AND METHODS

SCDVs were studied along patient age, β-globin genotypes, and fetal hemoglobin (HbF). Urine microalbumin/creatinine ratios (UM/Cr), trans-cranial doppler (TCD) and tricuspid regurgitant jet velocities (TRJV) were analyzed as well. Retinographies and overt vasculopathies were presented descriptively.

RESULTS

Among 20 females and 20 males [average 8.3 years (2.3-19 years)], 70% had HbSS/Sβ0, 22.5% HbSC and 7.5%-HbSβ+. The mean(±SD) HbF% was 17.4±12.7% (30% higher in <10 vs. ≥10 y/o, and 3 times higher in SS/Sβ0). Twenty-six patients received hydroxyurea and 13/26, L-glutamine. Thirty-six patients had TCDs within 1.4±0.9 years and all laboratory values were obtained within the last 12 months. TCDs showed low-normal velocities, but 2 were higher for HbSS/Sβ0 vs. HbSC/Sβ+ (MCA-96 vs. 86 cm/s, p=0.03; and PCA-50 vs. 41, p<0.001). Nineteen of 28 patients with echocardiograms had measurable TRJV (2.46±0.19 m/s); 9 had TRJV ≥2.5-2.8 m/s, but BNP ≤80 pg/ml. SS/Sβ0 was associated with higher UM/Cr. There were 2 cases with silent infarcts, 1-Moyamoya, 2-persistent macroalbuminuria, and 1-hematuria/renal papillary necrosis. Most ≥9 y/o patients had retinographies without SCD-related changes. There was no correlation among TCD (MCA), TRJV, and UM/Cr (n=17); thus, in this subpopulation, pathologies of cerebral, cardiopulmonary, and renal vasculatures evolved independently. Patients with higher TRJV and/or overt vasculopathy (n=14) were older than ones without (12.5±4.7 vs. 6.1±3.1 y/o, p<0.001), and had lower HbF (11.4±7.6 vs. 20.6±13.8%, p=0.026).

CONCLUSION

While overt SCDVs are less frequent in children, age-dependent trends/surrogate markers suggest their early origination in youth, justifying intense screening to prevent their progression with disease-modifying measures.

Advancing Cardiovascular Risk Assessment with Artificial Intelligence: Opportunities and Implications in North Carolina

Cardiovascular disease mortality is increasing in North Carolina with persistent inequality by race, income, and location. Artificial intelligence (AI) can repurpose the widely available electrocardiogram (ECG) for enhanced assessment of cardiac dysfunction. By identifying accelerated cardiac aging from the ECG, AI offers novel insights into risk assessment and prevention.

Regional Myopericarditis Mimicking Inferior Myocardial Infarction Following COVID-19 Vaccination: A Rare Adverse Event

We present the case of a 41-year-old man who developed myopericarditis after receiving the Pfizer COVID-19 vaccine. The patient experienced a sudden onset of chest and abdominal pain 16 days after vaccination. Electrocardiogram findings revealed deep T-wave inversion and minimal ST-segment elevation. Further investigation through coronary artery angiography and computed tomography identified an anomalous left main coronary artery. Magnetic resonance imaging confirmed the diagnosis of myopericarditis. This case highlights the importance of considering myopericarditis as a potential cause of chest pain and elevated cardiac biomarkers following COVID-19 vaccination, particularly in young individuals. Clinicians should be aware of this adverse event and include it in the differential diagnosis for patients presenting with similar symptoms after vaccination.

Characteristics of sudden death by clinical criteria

Sudden death is a leading cause of deaths nationally. Definitions of sudden death vary greatly, resulting in imprecise estimates of its frequency and incomplete knowledge of its risk factors. The degree to which time-based and coronary artery disease (CAD) criteria impacts estimates of sudden death frequency and risk factors is unknown. Here, we apply these criteria to a registry of all-cause sudden death to assess its impact on sudden death frequency and risk factors. The sudden unexpected death in North Carolina (SUDDEN) project is a registry of out of-hospital, adjudicated, sudden unexpected deaths attended by Emergency Medical Services. Deaths were not excluded by time since last seen or alive or by prior symptoms or diagnosis of CAD. Common criteria for sudden death based on time since last seen alive (both 24 hours and 1 hour) and prior diagnosis of CAD were applied to the SUDDEN case registry. The proportion of cases satisfying each of the 4 criteria was calculated. Characteristics of victims within each restrictive set of criteria were measured and compared to the SUDDEN registry. There were 296 qualifying sudden deaths. Application of 24 hour and 1 hour timing criteria compared to no timing criteria reduced cases by 25.0% and 69.6%, respectively. Addition of CAD criteria to each timing criterion further reduced qualifying cases, for a total reduction of 81.8% and 90.5%, respectively. However, characteristics among victims meeting restrictive criteria remained similar to the unrestricted population. Timing and CAD criteria dramatically reduces estimates of the number of sudden deaths without significantly impacting victim characteristics.

Automatic electronic reporting improved the completeness of AMI and stroke incident surveillance in Tianjin, China: a modeling study

BACKGROUND

AMI and stroke are the leading causes of premature mortality and hospitalizations in China. Incidence data at the population level for the two diseases is limited and the reliability and completeness of the existing incidence registry have not been investigated. We aim to assess if the completeness of case ascertainment of AMI and stroke incidence has improved since the implementation of electronic reporting and to estimate the incidence of AMI and stroke in Tianjin, China.

METHODS

We applied the DisMod II program to model the incidence of AMI and stroke from other epidemiological indicators. Inputs include mortality rates from Tianjin's mortality surveillance system, and the point prevalence, remission rates and relative risks taken from IHME's Global Burden of Disease studies. The completeness of AMI and stroke incidence reporting was assessed by comparing the sex and age-specific incidence rates derived from the incidence surveillance system with the modeled incidence rates.

RESULTS

The age and sex standardized modeled incidence per 100,000 person-year decreased (p < 0.0001) from 138 in 2007 to 119 in 2015 for AMI and increased (p < 0.0001) from 520 in 2007 to 534 in 2015 for stroke. The overall completeness of incidence report was 36% (95% CI 35-38%) for AMI and 54% (95% CI 53-55%) for stroke. The completeness was higher in men than in women for both AMI (42% vs 30%, p < 0.0001) and stroke (55% vs 53%, p < 0.0001) and was higher in residents aged 30-59 than those aged 60 or older for AMI (57% vs 38%, p < 0.0001). The completeness of reporting increased by 7.2 (95% CI 4.6-9.7) and 15.7 (95% CI 14.4-16.9) percentage points for AMI and stroke, respectively, from 2007 to 2015 among those aged 30 or above. The increases were observed in both men and women (p < 0.0001) and were more profound (p < 0.0001) among those aged between 30 and 59 and occurred primarily during the 2010 and 2015 period.

CONCLUSIONS

Completeness of AMI and stroke incidence surveillance was low in Tianjin but has improved in recent years primarily owing to the incorporation of an automatic reporting component into the information systems of health facilities.

A review of the causes and risk factors for sudden unexpected death in the young

Sudden unexpected death in the young (SUDY) is a tragic event resulting in the fatality of seemingly healthy individuals between the ages of one and 40 years. Whilst studies have been performed on sudden unexpected death in infants, children, and adults respectively, little is known about trends in risk factors and causes of death of SUDY cases. Understanding the factors surrounding these deaths could lead to targeted interventions for at-risk individuals. Hence, a systematic approach to investigate the reported possible causes of SUDY was employed using three major databases and Primo, wherein 67 relevant articles were identified and 2 additional guidelines were read. Sudden unexpected death in epilepsy and sudden cardiac events were well-established causes of death with risk factors such as male predominance, substance use and a familial history identified. It was acknowledged that while the cause of death is established following post-mortem examination in many cases, some remain non-specific or undetermined. Considering the genetic etiology, these cases would be ideal candidates for molecular autopsies in the future. Thus, this review emphasized the significance of acquiring the relevant information to aid in resolving cause of death of these SUDY cases and subsequently highlighted the potential for further studies on risk factors and the value of molecular autopsies.

Unique clinical features and long term follow up of survivors of sudden cardiac death in an Asian multicenter study

There has been no long-term clinical follow-up data of survivors or victims of sudden cardiac death (SCD). The Taiwan multi-center sudden arrhythmia death syndrome follow-up and clinical study (TFS-SADS) is a collaborative multi-center study with median follow-up time 43 months. In this cohort, the clinical characteristics of these SADS patients were compared with those with ischemic heart disease (IHD). In this SCD cohort, around half (42%) were patients with IHD, which was different from Caucasian SCD cohorts. Among those with normal heart, most had Brugada syndrome (BrS). Compared to those with SADS, patients with IHD were older, more males and more comorbidities, more arrhythmic death, and lower left ventricular ejection fraction. In the long-term follow-up, patients with SADS had a better survival than those with IHD (p < 0.001). In the Cox regression analysis to identify the independent predictors of mortality, older age, lower LVEF, prior myocardial infarction and history of out-of-hospital cardiac arrest were associated with higher mortality and beta blocker use and idiopathic ventricular fibrillation or tachycardia (IVF/IVT) with a better survival during follow-up. History of prior MI was associated with more arrhythmic death. Several distinct features of SCD were found in the Asia-Pacific region, such as higher proportion of SADS, poorer prognosis of LQTS and better prognosis of IVF/IVT. Patients with SADS had a better survival than those with IHD. For those with SADS, patients with channelopathy had a better survival than those with cardiomyopathy.

Mental Disorders, Substance Use Disorders, and Psychotropic Medication Use Among Sudden-Death Victims

OBJECTIVE

The authors sought to estimate the prevalence of mental and substance use disorders and psychotropic medication prescriptions among working-age sudden-death victims.

METHODS

Using a written protocol, the authors screened for sudden deaths attended by emergency medical services (EMS) in a large metropolitan county in North Carolina from March 1, 2013, to February 28, 2015. Sudden-death cases were adjudicated by three cardiologists. Mental health and chronic disease diagnoses and treatments were abstracted from EMS, medical examiner, toxicology, and autopsy reports and from clinical records for the past 5 years before death.

RESULTS

Sudden death was identified for 399 adults ages 18-64 years, 270 of whom had available medical records. Most sudden-death victims were White (63%) and male (65%), had a comorbid condition such as hypertension or respiratory disease, and had a mean±SD age of death of 53.6±8.8 years. Most victims (59%) had at least one mental health or substance use disorder documented in a recent medical record; 76%-78% of victims with a mental disorder had a documented psychotropic medication prescription. However, fewer than one-half (41%) had a documented referral to a mental health professional. The most common diagnostic categories were depressive, anxiety, and alcohol-related disorders. Almost one-half (46%) of the victims had a recent psychotropic prescription, most commonly antidepressants (29%) and benzodiazepines (19%).

CONCLUSIONS

Mental illness, substance use disorders, and psychotropic medication prescriptions were prevalent among sudden-death victims. The health care needs of these individuals may be better addressed by collaborative care for general medical and mental disorders.

Impact of Racial and Gender Variations in Patients With Out-of-hospital Cardiac Arrest: A Nation-Wide Study

The overall incidence of Out-of-hospital Cardiac Arrest (OHCA) is decreasing worldwide due to emergency responses, but there are gender and racial differences in the incidence of OHCA, which remain under investigation. Our aim was to identify the incidence, gender, and racial disparities in patients admitted with OHCA. The National Inpatient Sample Database is one of the largest all-payer inpatient database. It was queried to identify patients 18 years or older who were hospitalized with the principal diagnosis of OHCA. There was a total of 85,988 patients who were discharged with a diagnosis classified as OHCA using the ICD-9 code for a period of 2 years. The mean age of the patients who had presented to the hospital with OHCA was 64.3 (±18.5 years). Overall, a greater number of males suffered from OHCA were compared with female population of (48,635 vs 37,366; P < 0.0001). The incidence of OHCA was higher among Caucasians as compared with African Americans (54,812, 63.8% vs 13,787, 16%; P < 0.0001). In-hospital deaths after OHCA were 43,024 (50%). But African Americans had higher mortality than Caucasians after hospitalization for OHCA (adjusted odds ratio, 1.23; 95% confidence interval, 1.18-1.26; P < 0.01). We observed significant differences in gender and racial factors in the patients who were admitted to the hospital with a diagnosis of OHCA based on an analysis of the national inpatient database.

Symptoms prior to sudden death

Background

Sudden death accounts for up to 15% of all deaths among working age adults. A better understanding of victims’ medical care and symptoms reported at their last medical encounter may identify opportunities for interventions to prevent sudden deaths.

Methods

From 2013−15, all out-of-hospital deaths, ages 18–64 reported by Emergency Medical Services (EMS) in Wake County, North Carolina were screened and adjudicated to identify 399 victims of sudden death, 264 of whom had available medical records. Demographic and clinical characteristics and prescribed medications were compared between victims with versus without a medical encounter within one month preceding death with chi-square tests and t-tests, as appropriate. Symptoms reported in medical encounters within one month preceding death were analyzed.

Results

Among the 264 victims with available medical records, 73 (27.7%) had at least one encounter within a month preceding death. These victims were older and more likely to have multiple chronic illnesses, yet most were not prescribed evidence-based medicines. Of these 73 victims, 30 (41.1%) reported cardiac symptoms including dyspnea, edema, and chest pain.

Conclusions

Many victims seek medical care and report cardiac symptoms in the month prior to sudden death. However, medications that might prevent sudden death are under prescribed. These findings suggest that there are opportunities for intervention to prevent sudden death.

Variations in blood pressure control by medical comorbidities prior to sudden death

Patients with hypertension have increased risk of sudden death, but the impact of blood pressure control in sudden death is not clear. To better understand potential opportunities to prevent sudden, we assessed blood pressure control, comorbidities, and the number of recent medical encounters among all‐cause sudden death victims. Less than 40% of sudden death victims with hypertension had controlled blood pressure prior to death. Furthermore, increased frequency of medical visits and number of comorbidities were associated with better blood pressure control Strategies to address clinical inertia in hypertension treatment particularly for patients with fewer comorbidities may attenuate the risk of sudden death.

Association of 152 Biomarker Reference Intervals with All-Cause Mortality in Participants of a General United States Survey from 1999 to 2010

BACKGROUND:

Physicians sometimes consider whether or not to perform diagnostic testing in healthy people, but it is unknown whether nonextreme values of diagnostic tests typically encountered in such populations have any predictive ability, in particular for risk of death. The goal of this study was to quantify the associations among population reference intervals of 152 common biomarkers with all-cause mortality in a representative, nondiseased sample of adults in the United States.

METHODS:

The study used an observational cohort derived from the National Health and Nutrition Examination Survey (NHANES), a representative sample of the United States population consisting of 6 survey waves from 1999 to 2010 with linked mortality data (unweighted N=30 651) and a median followup of 6.1 years. We deployed an X-wide association study (XWAS) approach to systematically perform association testing of 152 diagnostic tests with all-cause mortality.

RESULTS:

After controlling for multiple hypotheses, we found that the values within reference intervals (10–90th percentiles) of 20 common biomarkers used as diagnostic tests or clinical measures were associated with all-cause mortality, including serum albumin, red cell distribution width, serum alkaline phosphatase, and others after adjusting for age (linear and quadratic terms), sex, race, income, chronic illness, and prior-year healthcare utilization. All biomarkers combined, however, explained only an additional 0.8% of the variance of mortality risk. We found modest year-to-year changes, or changes in association from survey wave to survey wave from 1999 to 2010 in the association sizes of biomarkers.

CONCLUSIONS:

Reference and nonoutlying variation in common biomarkers are consistently associated with mortality risk in the US population, but their additive contribution in explaining mortality risk is minor.

Mortality in patients with psychogenic nonepileptic seizures

Objective

To investigate the hypothesis that patients diagnosed with psychogenic nonepileptic seizures (PNES) on video-EEG monitoring (VEM) have increased mortality by comparison to the general population.

Methods

This retrospective cohort study included patients evaluated in VEM units of 3 tertiary hospitals in Melbourne, Australia, between January 1, 1995, and December 31, 2015. Diagnosis was based on consensus opinion of experienced epileptologists and neuropsychiatrists at each hospital. Mortality was determined in patients diagnosed with PNES, epilepsy, or both conditions by linkage to the Australian National Death Index. Lifetime history of psychiatric disorders in PNES was determined from formal neuropsychiatric reports.

Results

A total of 5,508 patients underwent VEM. A total of 674 (12.2%) were diagnosed with PNES, 3064 (55.6%) with epilepsy, 175 (3.2%) with both conditions, and 1,595 (29.0%) received other diagnoses or had no diagnosis made. The standardized mortality ratio (SMR) of patients diagnosed with PNES was 2.5 (95% confidence interval [CI] 2.0–3.3). Those younger than 30 had an 8-fold higher risk of death (95% CI 3.4–19.8). Direct comparison revealed no significant difference in mortality rate between diagnostic groups. Among deaths in patients diagnosed with PNES (n = 55), external causes contributed 18%, with 20% of deaths in those younger than 50 years attributed to suicide, and “epilepsy” was recorded as the cause of death in 24%.

Conclusions

Patients diagnosed with PNES have a SMR 2.5 times above the general population, dying at a rate comparable to those with drug-resistant epilepsy. This emphasizes the importance of prompt diagnosis, identification of risk factors, and implementation of appropriate strategies to prevent potential avoidable deaths.

Epidemiology and Outcomes from Out-of-Hospital Cardiac Arrest in Kuwait

Background

Out-of-hospital cardiac arrest (OHCA) survival remains low in most countries. Few studies examine OHCA outcomes out of the Middle East region. This is the first study to describe characteristics and outcomes of patients with OHCA treated by emergency medical services (EMS) in regions of Kuwait.

Objectives

To describe characteristics and outcomes of adult patients affected with OHCA in regions of Kuwait.

Methods

This was a retrospective observational study on all adult OHCA patients transported by EMS to regional emergency departments over a 10- month period (21 February–31 December 2017). Data were collected from various sources: national emergency medical services archived data, emergency department, intensive care unit, and cardiac care unit of two hospitals.

Results

A total of 332 EMS-treated OHCA cases were reviewed, and 286 incidents with OHCA from cardiac aetiology were included in the study. Most were non-Kuwaiti (60.8%) males (67.1%) with mean age 61 (+−16) years. Most OHCA cases occurred at home (76%) but with low witness rate (11.5%). Bystander CPR rate was low (8.7%). ROSC was achieved in ten patients (3.5%), but only 1 (0.3%) patient survived to hospital discharge.

Conclusion

OHCA survival rates in this region of Kuwait are low. Targeted measures such as creating cardiac registry, dispatcher-assisted CPR with ongoing training and quality improvement, and community-based CPR education program are needed to improve the survival rates of OHCA victims.

A case-crossover analysis of the relationship of air pollution with out-of-hospital sudden unexpected death in Wake County, North Carolina (2013-2015)

Out-of-hospital sudden unexpected deaths are non-accidental deaths that occur without obvious underlying causes and may account for 10% of natural deaths before age 65. Short-term exposure to ambient air pollution is associated with all-cause (non-accidental) and cause-specific (e.g., cardiovascular) mortality, and with immediate exposures often yielding the highest magnitude risk estimates. Few studies have focused on short-term exposure to air pollution and sudden unexpected deaths. Using the University of North Carolina Sudden Unexpected Death in North Carolina population, we examine associations between short-term criteria air pollutant exposures with sudden unexpected deaths using a time-stratified case-crossover design, with data on criteria air pollutants from the Environmental Protection Agency's Air Quality System. Odds ratios (OR) and 95% confidence intervals (CI) were estimated using conditional logistic regression with air pollutant exposures scaled to roughly inter-quartile ranges; models were adjusted for average temperature and relative humidity on event day and preceding 3 days. Potential for confounding by co-pollutants were examined in two pollutant models. ORs for PM_2.5 at lag day 1 were elevated (adjusted OR for 5 μg/m³ increase: 1.17 (0.98, 1.40)), and were robust to co-pollutant adjustment. Elevated odds were observed for SO₂ at lag day 0, and reduced odds for O₃ at lag day 0; however, these associations were somewhat attenuated toward the null (SO₂) or were not robust (O₃) to co-pollutant adjustment. This analysis in a racially and socioeconomically diverse cohort, with a more inclusive definition of sudden unexpected death than is typically employed offers evidence that PM_2.5 may be a clinically relevant trigger of sudden unexpected deaths in susceptible individuals.

Medication Use in Women and Men With Sudden Unexpected Death

BACKGROUND

In Wake County, NC, sudden unexpected death accounts for 10% to 15% of all natural deaths in individuals 18 to 64 years old. Medications such as aspirin, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, statins, and β-blockers are recommended in guidelines to reduce cardiovascular events and even sudden death (β-blockers). However, guidelines are often underpracticed, even in high-risk patients, with noted disparities in women.

OBJECTIVE

We assessed the relation between prescription of evidence-based medications and sudden unexpected death in Wake County, NC.

METHODS

We analyzed 399 cases of sudden unexpected death for the time period March 1, 2013 to February 28, 2015 in Wake County, NC. Medications were assessed from available medical examiner reports and medical records and grouped using the third level of the Anatomical Therapeutic Chemical Classification System (ATC) codes. This study was reviewed and exempt by the University of North Carolina's institutional review board.

RESULTS

Among 126 female and 273 male victims, women were prescribed more medications overall than men (6.5 vs 4.3, P = 0.001); however, the use of guideline-directed therapies was not different between genders in the chronic conditions associated with sudden death. Overall, there was remarkably low use of evidence-based medications.

CONCLUSIONS

Our findings highlight the need to improve prescribing of evidence-based medications and to further explore the relationship between undertreatment and sudden unexpected death.