Incidence of atrial fibrillation and flutter in Denmark in relation to country of origin: a nationwide register-based study.

BACKGROUND: Atrial fibrillation and flutter (AF) is the most common sustained arrhythmia with an increasing prevalence in Western countries. However, little is known about AF among immigrants compared to non-immigrants. AIM: To examine the incidence of hospital-diagnosed AF according to country of origin. METHOD: Immigrants were defined as individuals born outside Denmark by parents born outside Denmark. AF was defined as first-time diagnosis of AF. All individuals were followed from the age of 45 years from 1998 to 2017. The analyses were adjusted for sex, age, comorbidity, contact with the general practitioner and socioeconomic variables. Adjustment was conducted using standardised morbidity ratio weights, standardised to the Danish population in a marginal structural model. RESULTS: The study population consisted of 3,489,730 Danish individuals free of AF and 108,914 immigrants free of AF who had emigrated from the 10 most represented countries. A total of 323,005 individuals of Danish origin had an incident hospital diagnosis of AF, among the immigrants 7,300 developed AF. Adjusted hazard rate ratios (HRRs) of AF for immigrants from Iran (0.48 [95%CI:0.35;0.64]), Turkey (0.74 [95%CI:0.67;0.82]) and Bosnia-Herzegovina (0.42 [95%CI:0.22;0.79]) were low compared with Danish individuals. Immigrants from Sweden, Germany and Norway had an adjusted HRR of 1.13 [95%CI:1.03;1.23], 1.12 [95%CI:1.05;1.18] and 1.11 [95%CI:1.03;1.21], respectively (Danish individuals as reference). CONCLUSIONS: Substantial variation in the incidence of hospital-diagnosed AF according to country of origin was observed. The results may reflect true biological differences but could also reflect barriers to AF diagnosis for immigrants. Further efforts are warranted to determine the underlying mechanisms.

A novel approach for pharmacological substantiation of safety signals using plasma concentrations of medication and administrative/healthcare databases: A case study using Danish registries for an FDA warning on lamotrigine.

PHARMACOM-EPI is a novel framework to predict plasma concentrations of drugs at the time of occurrence of clinical outcomes. In early 2021, the U.S. Food and Drug Administration (FDA) issued a warning on the antiseizure drug lamotrigine claiming that it has the potential to increase the risk of arrhythmias and related sudden cardiac death due to a pharmacological sodium channel-blocking effect. We hypothesized that the risk of arrhythmias and related death is due to toxicity. We used the PHARMACOM-EPI framework to investigate the relationship between lamotrigine's plasma concentrations and the risk of death in older patients using real-world data. Danish nationwide administrative and healthcare registers were used as data sources and individuals aged 65 years or older during the period 1996 - 2018 were included in the study. According to the PHARMACOM-EPI framework, plasma concentrations of lamotrigine were predicted at the time of death and patients were categorized into non-toxic and toxic groups based on the therapeutic range of lamotrigine (3-15 mg/L). Over 1 year of treatment, the incidence rate ratio (IRR) of all-cause mortality was calculated between the propensities score matched toxic and non-toxic groups. In total, 7286 individuals were diagnosed with epilepsy and were exposed to lamotrigine, 432 of which had at least one plasma concentration measurement The pharmacometric model by Chavez et al. was used to predict lamotrigine's plasma concentrations considering the lowest absolute percentage error among identified models (14.25 %, 95 % CI: 11.68-16.23). The majority of lamotrigine associated deaths were cardiovascular-related and occurred among individuals with plasma concentrations in the toxic range. The IRR of mortality between the toxic group and non-toxic group was 3.37 [95 % CI: 1.44-8.32] and the cumulative incidence of all-cause mortality exponentially increased in the toxic range. Application of our novel framework PHARMACOM-EPI provided strong evidence to support our hypothesis that the increased risk of all-cause and cardiovascular death was associated with a toxic plasma concentration level of lamotrigine among older lamotrigine users.

Time trends of coronary procedures, guideline-based drugs and all-cause mortality following acute coronary syndrome in patients with bipolar disorder.

AIM: This study analyzed time trends in the use of coronary procedures, guideline-based drugs, and 1-year all-cause and presumed cardiovascular mortality (CV) following acute coronary syndrome (ACS) in patients with and without bipolar disorder (BD). METHOD: Using Danish registries 497 patients with ACS and BD in the period 1996-2016 were matched 1:2 on age, sex and year of ACS to patients without preexisting psychiatric disease. RESULTS: Patients with BD and ACS received fewer coronary angiography (CAG) compared to psychiatric healthy controls (PHC). However, the difference between the populations decreased over time. For percutaneous coronary intervention (PCI) and coronary artery bypass (CABG) no differences in trend over time were found. In general patients with BD redeemed fewer prescriptions of guideline-based tertiary prophylactic drugs compared to PHCs. The difference remains constant over time for all drugs except for acetylsalicylic acid, lipid-lowering drugs and beta blockers, where the difference decreased. The 1-year all-cause mortality gap and the presumed CV mortality gap remained unchanged. CONCLUSION: Despite improvements in treatment disparities regarding CAG, acetylsalicylic acid, lipid-lowering drugs and beta-blockers, the treatment gap remained unchanged concerning PCI and CABG. Likewise, patients with BD experienced a lower rate of the remaining redeemed prescriptions. The overall crude mortality risk ratio for patients with BD experiencing ACS remained unchanged over the study period compared to PHC.

Mental health among patients with non-Hodgkin lymphoma: A Danish nationwide study of psychotropic drug use in 8750 patients and 43 750 matched comparators.

Psychological distress following cancer diagnosis may lead to mental health complications including depression and anxiety. Non-Hodgkin lymphomas (NHLs) include indolent and aggressive subtypes for which treatment and prognosis differ widely. Incident use of psychotropic drugs (PDs-antidepressants, antipsychotics, and anxiolytics) and its correlation to lymphoma types can give insights into the psychological distress these patients endure. In this prospective matched cohort study, we used nationwide population-based registries to investigate the cumulative risk of PD use in NHL patients compared to a sex- and age-matched cohort from the Danish background population. In addition, contact patterns to psychiatric departments and incident intentional self-harm or completed suicide were explored. In total, 8750 NHL patients and 43 750 matched comparators were included (median age 68; male:female ratio 1.6). Median follow-up was 7.1 years. Two-year cumulative risk of PD use was higher in NHL patients (16.4%) as compared to the matched comparators (5.1%, p < .01); patients with aggressive NHL subtypes had the highest incidence. Prescription rates were higher in the first years after diagnosis but approached the rate of the matched population 5 years into survivorship in aggressive NHLs, whereas patients with indolent subtypes continued to be at higher risk. NHL patients had a slightly higher two-year risk of suicide/intentional self-harm (0.3%) as compared to the matched comparators (0.2%, p = .01). These results demonstrate that mental health complications among NHL patients are frequent. Routine assessment for symptoms of depression and anxiety should be consider as part of standard follow-up of NHL patients.

Unstable Angina as a Component of Primary Composite Endpoints in Clinical Cardiovascular Trials: Pros and Cons.

BACKGROUND: Unstable angina (UA) is a component of acute coronary syndrome that is only occasionally included in primary composite endpoints in clinical cardiovascular trials. The aim of this paper is to elucidate the potential benefits and disadvantages of including UA in such contexts. SUMMARY: UA comprises <10% of patients with acute coronary syndromes in contemporary settings. Based on the pathophysiological similarities, it is ideal as a part of a composite endpoint along with myocardial infarction (MI). By adding UA as a component of a primary composite endpoint, the number of events and feasibility of the trial should increase, thus decreasing its size and cost. Furthermore, UA has both economic and quality of life implications on a societal and an individual level. However, there are important challenges associated with the use of UA as an endpoint. With the introduction of high-sensitivity troponins, the number of individuals diagnosed with UA has decreased to rather low levels, with a reciprocal increase in the number of MI. In addition, UA is particularly challenging to define given the subjective assessment of the index symptoms, rendering a high risk of bias. To minimize bias, strict criteria are warranted, and events should be adjudicated by a blinded endpoint adjudication committee. KEY MESSAGES: UA should only be chosen as a component of a primary composite endpoint in cardiovascular trials after thoroughly evaluating the pros and cons. If it is chosen to include UA, appropriate precautions should be taken to minimize possible bias.

Hypothetical interventions on emergency ambulance and prehospital acetylsalicylic acid administration in myocardial infarction patients presenting without chest pain.

BACKGROUND: Myocardial infarction (MI) patients presenting without chest pain are a diagnostic challenge. They receive suboptimal prehospital management and have high mortality. To elucidate potential benefits of improved management, we analysed expected outcome among non-chest pain MI patients if hypothetically they (1) received emergency ambulances/acetylsalicylic acid (ASA) as often as observed for chest pain patients, and (2) all received emergency ambulance/ASA. METHODS: We sampled calls to emergency and non-emergency medical services for patients hospitalized with MI within 24 h and categorized calls as chest pain/non-chest pain. Outcomes were 30-day mortality and a 1-year combined outcome of re-infarction, heart failure admission, and mortality. Targeted minimum loss-based estimation was used for all statistical analyses. RESULTS: Among 5418 calls regarding MI patients, 24% (1309) were recorded with non-chest pain. In total, 90% (3689/4109) of chest pain and 40% (525/1309) of non-chest pain patients received an emergency ambulance, and 73% (2668/3632) and 37% (192/518) of chest pain and non-chest pain patients received prehospital ASA. Providing ambulances to all non-chest pain patients was not associated with improved survival. Prehospital administration of ASA to all emergency ambulance transports of non-chest pain MI patients was expected to reduce 30-day mortality by 5.3% (CI 95%: [1.7%;9%]) from 12.8% to 7.4%. No significant reduction was found for the 1-year combined outcome (2.6% CI 95% [- 2.9%;8.1%]). In comparison, the observed 30-day mortality was 3% among ambulance-transported chest pain MI patients. CONCLUSIONS: Our study found large differences in the prehospital management of MI patients with and without chest pain. Improved prehospital ASA administration to non-chest pain MI patients could possibly reduce 30-day mortality, but long-term effects appear limited. Non-chest pain MI patients are difficult to identify prehospital and possible unintended effects of ASA might outweigh the potential benefits of improving the prehospital management. Future research should investigate ways to improve the prehospital recognition of MI in the absence of chest pain.

Pharmacoepidemiological methods for computing the duration of pharmacological prescriptions using secondary data sources.

PURPOSE: In pharmacoepidemiology, correctly defining the exposure period of pharmacological treatment is a challenging step when information on the time in treatment is missing or incomplete. METHODS: In this review, we describe several methods for defining exposure to pharmacological treatments using secondary data sources that lack such information. RESULTS AND CONCLUSION: Several methods for assessing the duration of redeemed prescriptions and combining them into temporal sequences are available. We present a set of considerations to make researchers aware of the potentials and pitfalls of these methods that may aid in minimizing biases in research using these methods. Additionally, we highlight that, to date, there is no one-size-fits-all solution. Thus, the choice of method should be based on their area of applicability combined with a careful mapping to the research scenario under investigation.

Kawasaki disease, autoimmune disorders, and cancer: a register-based study.

Kawasaki disease has well-described cardiovascular complications. However, the association to autoimmunity and cancer in the long term is not well described. We investigated theses associations using a registry-based matched cohort follow-up study of patients diagnosed with Kawasaki disease. Patients with Kawasaki disease were included and matched 1:5 to a population control group, matched by birth year, sex and incident month of the Kawasaki disease diagnosis. A total of 820 cases < 21 years of age were identified. Median age at diagnosis was 3 years. Median follow-up time was 12 years. Patients with KD were at higher risk of being diagnosed with ischaemic heart disease at 10 years (HR 39.94 (95% CI 5.00-319.28)) and 30 years (HR 8.33 (95% CI 3.03-22.91)). The 10-, 20- and 30-year risks of developing autoimmune disorders were HR 4.23 (95% CI 3.01-5.94), HR 3.23 (95% CI 2.44-4.29) and 2.83 (95% CI, 2.17-3.68), all p < 0.001. Cancer risk was increased after 30 years (HR 2.42 (95% CI, 1.09-5.34)). All-cause mortality after 35 years was also significantly increased (HR 3.14 (95% CI, 1.03-9.60)). Children with KD have increased long-term risks of ischaemic heart disease also of autoimmune disease and cancer, as well as an increased all-cause mortality. The surprisingly increased risk of autoimmunity must be investigated further. What is known: • Kawasaki disease is characterized by acute vasculitis and inflammation that can affect the coronary arteries. • Anti-inflammatory medicine is effective in the acute stages of the disease. What is new: • Children with Kawasaki disease have an increased risk of developing autoimmune disease in the long term. • Kawasaki disease is associated with a slightly increased mortality rate driven by non-cardiovascular causes.

Risk of atrial fibrillation after pacemaker implantation: A nationwide Danish registry-based follow-up study.

BACKGROUND: The overall risk of atrial fibrillation (AF) among patients with pacemaker (PM) in comparison to control cohort is unknown. PURPOSE: To investigate the risk of AF after implantation of a PM in an AF-naive population in comparison to an age- and sex-matched PM- and AF-free population cohort. METHODS: All patients with a dual chamber PM (DDD) implanted between 2000 and 2014 without a known history of AF were included (n = 17,428). To compare, a general population cohort without pacemaker and a cohort with loop recorder was identified. Outcome was the cumulative incidence of AF within the first 2 years from 3-months after device implantation. RESULTS: At the end of first 3-months after device implantation, 16,383 patients were free of AF and were included in the current study. In comparison to controls (n = 86,167), patients with PM had higher cumulative incidence of AF (5.2% vs 2.7%, P < 0.001)). Due to interaction with age, patients were divided into three age-groups) and the relative risk for the diagnosis of AF were: < 70 years (HR 4.46, 95% CI 3.65-5.44); 70-79 years (HR 2.60, 95% CI 2.27-2.98); and ≥ 80 years (HR 1.29, 95% CI 1.15-1.45). For comparison between PM and loop-recorder cohort (1:1 matching), 2202 patients were available in both groups. The incidence of AF within the first 2-years in the both groups was 7.9% vs. 8.4% (loop vs pacemaker). CONCLUSIONS: Patients with PM have an increased risk of being diagnosed with AF in comparison to general cohort likely due to continuous monitoring.

Incidence of heart failure after pacemaker implantation: a nationwide Danish Registry-based follow-up study.

AIMS: The objective of the current study is to investigate the risk of heart failure (HF) after implantation of a pacemaker (PM) with a right ventricular pacing (RVP) lead in comparison to a matched cohort without a PM and factors associated with this risk. METHODS AND RESULTS: All patients without a known history of HF who had a PM implanted with an RVP lead between 2000 and 2014 (n = 27 704) were identified using Danish nationwide registries. An age- and gender-matched control cohort (matched 1:5, n = 138 520) without PM and HF was identified to compare the risk. Outcome was the cumulative incidence of HF including fatal HF within the first 2 years of PM implantation, with all-cause mortality and myocardial infarction (MI) as competing risks. Due to violation of proportional hazards, the follow-up period was divided into three time-intervals: <30 days, 30-180 days, and >180 days-2 years. The cumulative incidence of HF including fatal HF was observed in 2937 (10.6%) PM patients. Risks for the three time-intervals were <30 days [hazard ratio (HR) 5.98, 95% CI 5.19-6.90], 30-180 days (HR 1.84, 95% CI 1.71-1.98), and >180 days (HR 1.11, 95% CI 1.04-1.17). Among patients with a PM device, factors associated with increased risk of HF were male sex (HR 1.33, 95% CI 1.24-1.43), presence of chronic kidney disease (CKD) (HR 1.64, 95% CI 1.29-2.09), and prior MI (1.77, 95% 1.50-2.09). CONCLUSIONS: Pacemaker with an RVP lead is strongly associated with risk of HF specifically within the first 6 months. Patients with antecedent history of MI and CKD had substantially increased risk.

Mortality and return to work in patients transported by emergency ambulance after involvement in a traffic accident.

INTRODUCTION/BACKGROUND: Traffic accidents constitute a common reason for injury. Little is known about long-term outcomes for patients following a traffic accident. Therefore, in this present paper, we examine 1-day, 30-day and 1-year mortality, and return to work (RTW) during a 1-year period. METHODS: Patients (between 18 and 65 years of age) who had an ambulance dispatched to them following a traffic accident and who were employed prior to the accident were identified from the Electronic Prehospital Emergency Patient (amPHI™) database in the North Denmark Region (catchment population ≈600,000) during 2006-2014. Outcomes of 1- and 30- and 365-day mortality and 1-year return to work (RTW), with mortality as competing risk. We stratified by intensive care unit (ICU) admission; and the anatomical region of injury (head/neck, thorax, abdomen, extremities and multiple injuries) is reported. RESULTS: Of 6072 patients in our study population, 59 (1%) died within 1 day and 76 (1.3%) within 30 days; 88 (1.5%) were dead within a year. Thirty-day mortality was 1.7% for the 290 patients admitted to the ICU, and 1.2% for the remaining 5782 patients. Within the study population, RTW rate was 92.7% (N = 5984). RTW was 84.8% among 290 ICU-admitted patients versus 93.1% for the remaining 5782 patients. RTW rate was 94.6% for the 1793 patients discharged with a diagnosis of head/neck injury. Of 671 patients with a discharge diagnosis for the thoracic region, 92.6% returned to work. Of 402 patients with abdominal injury diagnoses, 90.8% returned to work. Of 1603 patients discharged with a diagnosis of extremity injury, the RTW rate was 93.6%. Of 192 patients with a discharge diagnosis of injury in multiple regions, 91.7% returned to work. CONCLUSION: Overall, mortality rates were low and RTW rates high in patients who had an ambulance dispatched due to a traffic accident. Those admitted to the ICU had the lowest RTW rate, yet still around 80% returned to work.

Long-term aspirin adherence following myocardial infarction and risk of cardiovascular events.

BACKGROUND AND AIMS: Aspirin is considered mandatory after myocardial infarction (MI). However, its long-term efficacy has been questioned. This study investigated the effectiveness of long-term aspirin after MI. METHODS: Patients ≥ 40 years with MI from 2004-2017 who were adherent to aspirin one year after MI were included from Danish nationwide registries. At 2, 4, 6, and 8 years after MI, continued adherence to aspirin was evaluated. Absolute and relative risks of MI, stroke, or death at 2 years from each timepoint were calculated using multivariable logistic regression analysis with average treatment effect modeling standardized for age, sex, and comorbidities. Subgroup analyses were stratified by sex and age > and ≤ 65 years. RESULTS: Among 40 114 individuals included, the risk of the composite endpoint was significantly higher for nonadherent patients at all timepoints. The absolute risk was highest at 2-4 years after MI for both adherent (8.34%, 95% confidence interval [CI]: 8.05-8.64%) and nonadherent patients (10.72%, 95% CI: 9.78-11.66%). The relative risk associated with nonadherence decreased from 4 years after index-MI and onwards: 1.41 (95% CI: 1.27-1.55) at 4-6 years and 1.21 (95% CI: 1.06-1.36) at 8-10 years (Ptrend = 0.056). Aspirin nonadherence in women and individuals > 65 years was not associated with increased risk. Pinteraction at each of the timepoints: Age-<0.001, <0.001, 0.002, 0.51; Sex - 0.25, 0.02, 0.02, 0.82. CONCLUSION: Nonadherence to long-term aspirin was associated with increased risk of MI, stroke, or death, but not in women or individuals > 65 years. The risk decreased from 4 years after MI with near statistical significance.

Patients with eosinophilic oesophagitis in Denmark have higher use of psychotropic drugs: A Danish nationwide study of psychotropic drug use in 3367 patients and 16,835 matched comparators.

BACKGROUND: Eosinophilic oesophagitis (EoE) is a chronic, immune-mediated disease of the oesophagus. Eosinophilic oesophagitis is associated with a substantial disease burden affecting the quality of life and affecting mental health. There are limited data describing the incidence of psychiatric disorders and the use of psychotropic drugs (PDs) in EoE patients. OBJECTIVES: The aim was to investigate whether EoE patients in Denmark have higher use of PDs, contacts with the department of psychiatry, and attempts of suicide or intentional self-harm compared with the general population after being diagnosed with EoE. METHODS: This study was a nationwide, population-based register study including 3367 EoE patients and 16,835 age- and sex-matched comparators. A register-based EoE definition was used to identify cases. Incident PD use was extracted from the prescription register and information regarding psychiatric contacts was retrieved from the Danish Psychiatric Central Research Register. RESULTS: The 5-year incidence of PD use in EoE patients was 13.8% compared to 7.1% of the matched comparators (Hazard ratio 1.83; confidence interval 1.6-2.0; p ≤ 0.001). Antidepressants were the most frequently prescribed PD, whereas antipsychotics were the least prescribed PD. Increasing age, lower educational level, and comorbidity (Charlson Comorbidity Index score ≥1) were associated with the prescription of PDs. The risk of PD use was lower in men than in women with EoE. CONCLUSION: Treatment with PDs were more common in EoE patients after they were diagnosed than in the general Danish population, indicating that EoE patients have an increased risk of psychiatric disorders.

Oral anticoagulation therapy initiation in patients with atrial fibrillation in relation to world region of origin: a register-based nationwide study.

BACKGROUND: Atrial fibrillation (AF) is the most common sustained arrhythmia and results in a high risk of stroke. The number of immigrants is increasing globally, but little is known about potential differences in AF care across migrant populations. AIM: To investigate if initiation of oral anticoagulation therapy (OAC) differs for patients with incident AF in relation to country of origin. METHODS: A nationwide register-based study covering 1999-2017. AF was defined as a first-time diagnosis of AF and a high risk of stroke. Stroke risk was defined according to guidelines from the European Society of Cardiology (ESC). Poisson regression adjusted for sex, age, socioeconomic position and comorbidity was made to compute incidence rate ratios (IRR) for initiation of OAC. RESULTS: The AF population included 254 586 individuals of Danish origin, 6673 of Western origin and 3757 of non-Western origin. Overall, OAC was initiated within -30/+90 days relative to the AF diagnosis in 50.3% of individuals of Danish origin initiated OAC, 49.6% of Western origin and 44.5% of non-Western origin. Immigrants from non-Western countries had significantly lower adjusted IRR of initiating OAC according to all ESC guidelines compared with patients of Danish origin. The adjusted IRRs ranged from 0.73 (95% CI: 0.66 to 0.80) following the launch of the 2010 ESC guideline to 0.89 (95% CI: 0.82 to 0.97) following the launch of the 2001 ESC guideline. CONCLUSION: Patients with AF with a high risk of stroke of non-Western origin have persistently experienced a lower chance of initiating OAC compared with patients of Danish origin during the last decades.

Association between mortality and phone-line waiting time for non-urgent medical care: a Danish registry-based cohort study.

BACKGROUND AND IMPORTANCE: Telephone calls are often patients' first healthcare service contact, outcomes associated with waiting times are unknown. OBJECTIVES: Examine the association between waiting time to answer for a medical helpline and 1- and 30-day mortality. DESIGN, SETTING AND PARTICIPANTS: Registry-based cohort study using phone calls data (January 2014 to December 2018) to the Capital Region of Denmark's medical helpline. The service refers to hospital assessment/treatment, dispatches ambulances, or suggests self-care guidance. EXPOSURE: Waiting time was grouped into the following time intervals in accordance with political service targets for waiting time in the Capital Region: <30 s, 0:30-2:59, 3-9:59, and ≥10 min. OUTCOME MEASURES AND ANALYSIS: The association between time intervals and 1- and 30-day mortality per call was calculated using logistic regression with strata defined by age and sex. MAIN RESULTS: In total, 1 244 252 callers were included, phoning 3 956 243 times, and 78% of calls waited <10 min. Among callers, 30-day mortality was 1% (16 560 deaths). For calls by females aged 85-110 30-day mortality increased with longer waiting time, particularly within the first minute: 9.6% for waiting time <30 s, 10.8% between 30 s and 1 minute and 9.1% between 1 and 2 minutes. For calls by males aged 85-110 30-day mortality was 11.1%, 12.9% and 11.1%, respectively. Additionally, among calls with a Charlson score of 2 or higher, longer waiting times were likewise associated with increased mortality. For calls by females aged 85-110 30-day mortality was 11.6% for waiting time <30 s, 12.9% between 30 s and 1 minute and 11.2% between 1 and 2 minutes. For calls by males aged 85-110 30-day mortality was 12.7%, 14.1% and 12.6%, respectively. Fewer ambulances were dispatched with longer waiting times (4%/2%) with waiting times <30 s and >10 min. CONCLUSION: Longer waiting times for telephone contact to a medical helpline were associated with increased 1- and 30-day mortality within the first minute, especially among elderly or more comorbid callers.

Ambulance response times and 30-day mortality: a Copenhagen (Denmark) registry study.

BACKGROUND AND IMPORTANCE: Ensuring prompt ambulance responses is complicated and costly. It is a general conception that short response times save lives, but the actual knowledge is limited. OBJECTIVE: To examine the association between the response times of ambulances with lights and sirens and 30-day mortality. DESIGN: A registry-based cohort study using data collected from 2014-2018. SETTINGS AND PARTICIPANTS: This study included 182 895 individuals who, during 2014-2018, were dispatched 266 265 ambulances in the Capital Region of Denmark. OUTCOME MEASURES AND ANALYSIS: The primary outcome was 30-day mortality. Subgroup analyses were performed on out-of-hospital cardiac arrests, ambulance response priority subtypes, and caller-reported symptoms of chest pain, dyspnoea, unconsciousness, and traffic accidents. The relation between variables and 30-day mortality was examined with logistic regression. RESULTS: Unadjusted, short response times were associated with higher 30-day mortality rates across unadjusted response time quartiles (0-6.39 min: 9%; 6.40-8.60 min: 7.5%, 8.61-11.80 min: 6.6%, >11.80 min: 5.5%). This inverse relationship was consistent across subgroups, including chest pain, dyspnoea, unconsciousness, and response priority subtypes. For traffic accidents, no significant results were found. In the case of out-of-hospital cardiac arrests, longer response times of up to 10 min correlated with increased 30-day mortality rates (0-6.39 min: 84.1%; 6.40-8.60 min: 86.7%, 8.61-11.8 min: 87.7%, >11.80 min: 85.5%). Multivariable-adjusted logistic regression analysis showed that age, sex, Charlson comorbidity score, and call-related symptoms were associated with 30-day mortality, but response time was not (OR: 1.00 (95% CI [0.99-1.00])). CONCLUSION: Longer ambulance response times were not associated with increased mortality, except for out-of-hospital cardiac arrests.

Prodromal complaints and 30-day survival after emergency medical services-witnessed out-of-hospital cardiac arrest.

BACKGROUND: Out-of-hospital cardiac arrest (OHCA) is a frequent and lethal condition with a yearly incidence of approximately 5000 in Denmark. Thirty-day survival is associated with the patient's prodromal complaints prior to cardiac arrest. This paper examines the odds of 30-day survival dependent on the reported prodromal complaints among OHCAs witnessed by the emergency medical services (EMS). METHODS: EMS-witnessed OHCAs in the Capital Region of Denmark from 2016-2018 were included. Calls to the emergency number 1-1-2 and the medical helpline for out-of-hours were analyzed according to the Danish Index; data regarding the OHCA was collected from the Danish Cardiac Arrest Registry. We performed multiple logistic regression to calculate the odds ratio (OR) of 30-day survival with adjustment for sex and age. RESULTS: We identified 311 eligible OHCAs of which 79 (25.4%) survived. The most commonly reported complaints were dyspnea (n = 209, OR 0.79 [95% CI 0.46: 1.36]) and 'feeling generally unwell' (n = 185, OR 1.07 [95% CI 0.63: 1.81]). Chest pain (OR 9.16 [95% CI 5.09:16.9]) and heart palpitations (OR 3.15 [95% CI 1.07:9.46]) had the highest ORs, indicating favorable odds for 30-day survival, while unresponsiveness (OR 0.22 [95% CI 0.11:0.43]) and blue skin or lips (OR 0.30, 95% CI 0.09, 0.81) had the lowest, indicating lesser odds of 30-day survival. CONCLUSION: Experiencing chest pain or heart palpitations prior to EMS-witnessed OHCA was associated with higher 30-day survival. Conversely, complaints of unresponsiveness or having blue skin or lips implied reduced odds of 30-day survival.

Risk of dementia among older patients with lymphoma: A Danish nationwide matched cohort study.

INTRODUCTION: Treatment of lymphoma can be associated with cognitive challenges, and some patients may fear development of dementia as long-term complication. Studies report a lower risk of dementia after cancer. Some believe this difference to be a protective mechanism of cancer, others believe it to be driven by bias. The risk of developing dementia after lymphoma has not been investigated in a population-based setting. The aim of this study was to identify the risk of being diagnosed with dementia after lymphoma treatment. MATERIALS AND METHODS: This Danish nationwide matched cohort study included patients aged ≥65 years with a first-time diagnosis of a non-central nervous system lymphoma between 2005 and 2018 in complete remission after treatment with chemotherapy. Patients diagnosed with dementia or treated with dementia medication before lymphoma diagnosis were excluded. Each patient was matched 1:5 on sex, year of birth, and a modified Charlson comorbidity index. Patients and matched comparators were followed from the corresponding patient's date of complete remission. The risk of developing dementia was calculated using cause-specific hazard ratios (HR), and the cumulative risk was estimated by Aalen-Johansen with death as the competing risk. RESULTS: A total of 3,244 patients and 16,220 matched comparators were included in the study. There was no difference in risk of all-cause dementia among patients with lymphoma compared to matched comparators with cause-specific HR of 0.85 (95% confidence interval [CI]: 0.70;1.04). The risk of both Alzheimer's disease and non-Alzheimer's dementia was equal among patients and comparators: HR 0.89 (95% CI: 0.66;1.21) and 0.82 (95% CI: 0.63;1.07), respectively. Stratified by lymphoma subtype, age, or year of diagnosis, the risk of all-cause dementia remained equal among patients and matched comparators. The cumulative risk of all-cause dementia was significantly lower among patients with lymphoma compared to matched comparators (Gray's test p < 0.001), probably reflecting higher mortality in patients with lymphoma. DISCUSSION: The risk of all-cause dementia, Alzheimer's disease, and non-Alzheimer's dementia was equal among older patients with lymphoma compared to matched comparators. Our data suggests that risk of developing dementia is not changed after lymphoma treatment.

Prediction model for future OHCAs based on geospatial and demographic data: An observational study.

This study used demographic data in a novel prediction model to identify areas with high risk of out-of-hospital cardiac arrest (OHCA) in order to target prehospital preparedness. We combined data from the nationwide Danish Cardiac Arrest Registry with geographical- and demographic data on a hectare level. Hectares were classified in a hierarchy according to characteristics and pooled to square kilometers (km2). Historical OHCA incidence of each hectare group was supplemented with a predicted annual risk of at least 1 OHCA to ensure future applicability. We recorded 19,090 valid OHCAs during 2016 to 2019. The mean annual OHCA rate was highest in residential areas with no point of public interest and 100 to 1000 residents per hectare (9.7/year/km2) followed by pedestrian streets with multiple shops (5.8/year/km2), areas with no point of public interest and 50 to 100 residents (5.5/year/km2), and malls with a mean annual incidence per km2 of 4.6. Other high incidence areas were public transport stations, schools and areas without a point of public interest and 10 to 50 residents. These areas combined constitute 1496 km2 annually corresponding to 3.4% of the total area of Denmark and account for 65% of the OHCA incidence. Our prediction model confirms these areas to be of high risk and outperforms simple previous incidence in identifying future risk-sites. Two thirds of out-of-hospital cardiac arrests were identified in only 3.4% of the area of Denmark. This area was easily identified as having multiple residents or having airports, malls, pedestrian shopping streets or schools. This result has important implications for targeted intervention such as automatic defibrillators available to the public. Further, demographic information should be considered when implementing such interventions.