Ebullition dominates methane emissions in stratified coastal waters.

Coastal areas are an important source of methane (CH4). However, the exact origins of CH4 in the surface waters of coastal regions, which in turn drive sea-air emissions, remain uncertain. To gain a comprehensive understanding of the current and future climate change feedbacks, it is crucial to identify these CH4 sources and processes that regulate its formation and oxidation. This study investigated coastal CH4 dynamics by comparing water column data from six stations located in the brackish Tvärminne Archipelago, Baltic Sea. The sediment biogeochemistry and microbiology were further investigated at two stations (i.e., nearshore and offshore). These stations differed in terms of stratification, bottom water redox conditions, and organic matter loading. At the nearshore station, CH4 diffusion from the sediment into the water column was negligible, because nearly all CH4 was oxidized within the upper sediment column before reaching the sediment surface. On the other hand, at the offshore station, there was significant benthic diffusion of CH4, albeit the majority underwent oxidation before reaching the sediment-water interface, due to shoaling of the sulfate methane transition zone (SMTZ). The potential contribution of CH4 production in the water column was evaluated and was found to be negligible. After examining the isotopic signatures of δ13C-CH4 across the sediment and water column, it became apparent that the surface water δ13C-CH4 values observed in areas with thermal stratification could not be explained by diffusion, advective fluxes, nor production in the water column. In fact, these values bore a remarkable resemblance to those detected below the SMTZ. This supports the hypothesis that the source of CH4 in surface waters is more likely to originate from ebullition than diffusion in stratified brackish coastal systems.

Equine chorionic gonadotropin (eCG) treatment in heifers: Double ovulation, twinning rate, and pregnancy losses in twin pregnancies.

This study aimed to evaluate the effects of different doses of equine chorionic gonadotropin (eCG; 200 and 300 IU) administered at the end of a fixed-time artificial insemination (FTAI) treatment protocol on ovulation, pregnancy, and twin rates in Bos taurus beef heifers. In addition, pregnancy losses in heifers with singleton and twin pregnancies were determined. A total of 2382 Angus heifers treated with a 6-day estradiol/progesterone-based protocol for FTAI (J-Synch protocol) were randomly allocated to two experimental groups to receive 200 or 300 IU of eCG administered intramuscularly at the time of intravaginal progesterone device removal; FTAI was performed from 60 to 72 h after device removal. The pregnancy rate did not differ (P = 0.89) between the 200 and 300 IU eCG groups. The number of corpus luteum induced by both eCG doses was determined by ultrasonographic examination 14 days after insemination and those treated with 300 IU of eCG had a greater double ovulation rate (P < 0.05). In addition, 300 IU eCG treated heifers had a higher twinning rate on day 30 of gestation (P < 0.05) and parturition (P < 0.05). Pregnancy losses from 30 days of gestation to calving did not differ between heifers treated with 200 and 300 IU of eCG (P = 0.70). However, regardless of the experimental group, heifers bearing twins had greater pregnancy losses than heifers with singletons (P < 0.05). In conclusion, reducing the dose of eCG from 300 to 200 IU under FTAI treatment protocol decreases double ovulation and twinning rates, maintaining a similar pregnancy rate in heifers. Nulliparous cows carrying two fetuses suffer greater pregnancy losses than cows with singletons.

Toxicology Screening in Sports-Related Sudden Cardiac Death: A Multinational Observational Study.

BACKGROUND: Knowledge of toxicological findings among sports-related sudden cardiac death (SrSCD) is scarce. OBJECTIVES: This study aimed to describe postmortem toxicology findings in a multinational cohort of young SrSCD. METHODS: Patients with sudden cardiac death (SCD) aged 12 to 49 years with a complete post mortem were included from Denmark, Spain, and Australia. Postmortem findings were compared between SrSCD and non-SrSCD, and toxicology findings in SrSCD were assessed. RESULTS: We included 3,189 SCD, of which 219 (7%) were sports-related. SrSCD patients were younger (36 years vs 41 years; P < 0.001) and of male predominance (96% vs 75%; P < 0.001), and their death was more often caused by structural cardiac disease (68% vs 61%; P = 0.038). Positive toxicology screenings were significantly less likely among SrSCD than non-SrSCD (12% vs 43%; P < 0.001), corresponding to 82% lower odds of a positive toxicology screening in SrSCD. Patient characteristics were similar between SrSCDs with positive and negative toxicology screenings, but deaths were more often unexplained (59% vs 34%). Nonopioid analgesics were the most common finding (3%), and SCD-associated drugs were detected in 6% of SrSCD. SUD was more prevalent among the SrSCD with positive toxicology (59% vs 34%). CONCLUSIONS: Sports-related SCD mainly occurred in younger men with structural heart disease. They had a significantly lower prevalence of a positive toxicology screening compared with non-SrSCD, and detection of SCD-associated drugs was rare.

Myocardial scarring and recurrence of ventricular arrhythmia in patients surviving an out-of-hospital cardiac arrest.

INTRODUCTION: Prediction of recurrent ventricular arrhythmia (VA) in survivors of an out-of-hospital cardiac arrest (OHCA) is important, but currently difficult. Risk of recurrence may be related to presence of myocardial scarring assessed with late gadolinium enhancement cardiac magnetic resonance (LGE-CMR). Our study aims to characterize myocardial scarring as defined by LGE-CMR in survivors of a VA-OHCA and investigate its potential role in the risk of new VA events. METHODS: Between 2015 and 2022, a total of 230 VA-OHCA patients without ST-segment elevation myocardial infarction had CMR before implantable cardioverter-defibrillator implantation for secondary prevention at Copenhagen University Hospital, Rigshospitalet, and Hospital Clínic, University of Barcelona, of which n = 170 patients had a conventional (no LGE protocol) CMR and n = 60 patients had LGE-CMR (including LGE protocol). Scar tissue including core, border zone (BZ) and BZ channels were automatically detected by specialized investigational software in patients with LGE-CMR. The primary endpoint was recurrent VA. RESULTS: After exclusion, n = 52 VA-OHCA patients with LGE-CMR and a mean left ventricular ejection fraction of 49 ± 16% were included, of which 18 (32%) patients reached the primary endpoint of VA. Patients with recurrent VA in exhibited greater scar mass, core mass, BZ mass, and presence of BZ channels compared with patients without recurrent VA. The presence of BZ channels identified patients with recurrent VA with 67% sensitivity and 85% specificity (area under the ROC curve (AUC) 0.76; 95% CI: 0.63-0.89; p < .001) and was the strongest predictor of the primary endpoint. CONCLUSIONS: The presence of BZ channels was the strongest predictor of recurrent VA in patients with an out of-hospital cardiac arrest and LGE-CMR.

Causes and consequences of acidification in the Baltic Sea: implications for monitoring and management.

Increasing atmospheric CO2 drives ocean acidification globally. In coastal seas, acidification trends can however be either counteracted or enhanced by other processes. Ecosystem effects of acidification are so far small in the Baltic Sea, but changes should be anticipated unless CO2 emissions are curbed. Possible future acidification trends in the Baltic Sea, conditional on CO2 emissions, climate change, and changes in productivity, can be assessed by means of model simulations. There are uncertainties regarding potential consequences for marine organisms, partly because of difficulties to assign critical thresholds, but also because of knowledge gaps regarding species' capacity to adapt. Increased temporal and spatial monitoring of inorganic carbon system parameters would allow a better understanding of current acidification trends and also improve the capacity to predict possible future changes. An additional benefit is that such measurements also provide quantitative estimates of productivity. The technology required for precise measurements of the inorganic carbon system is readily available today. Regularly updated status evaluations of acidification, and the inorganic carbon system in general, would support management when assessing climate change effects, eutrophication or characteristics of the pelagic habitats. This would, however, have to be based on a spatially and temporally sufficient monitoring program.

Use of Nonrecommended Drugs in Patients With Brugada Syndrome: A Danish Nationwide Cohort Study.

Background Patients with Brugada syndrome (BrS) are recommended to avoid drugs that may increase their risk of arrhythmic events. We examined treatment with such drugs in patients with BrS after their diagnosis. Methods and Results All Danish patients diagnosed with BrS (2006-2018) with >12 months of follow-up were identified from nationwide registries. Nonrecommended BrS drugs were grouped into drugs to "avoid" or "preferably avoid" according to http://www.brugadadrugs.org. Cox proportional hazards analyses were performed to identify factors associated with any nonrecommended BrS drug use, and logistic regression analyses were performed to examine associated risk of appropriate implantable cardioverter defibrillator therapy, mortality, and a combined end point indicating an arrhythmic event of delayed implantable cardioverter defibrillator implantation, appropriate implantable cardioverter defibrillator therapy, and mortality. During a median follow-up of 6.8 years, 93/270 (34.4%) patients with BrS (70.4% male, median age at diagnosis 46.1 years [interquartile range, 32.6-57.4]) were treated with ≥1 nonrecommended BrS drugs. No difference in any nonrecommended BrS drug use was identified comparing time before BrS diagnosis (12.6%) with each of the 5 years following BrS diagnosis (P>0.05). Factors associated with any nonrecommended BrS drug use after diagnosis were female sex (hazard ratio [HR]) 1.83 [95% CI, 1.15-2.90]), psychiatric disease (HR, 3.63 [1.89-6.99]), and prior use of any nonrecommended BrS drug (HR, 4.76 [2.45-9.25]). No significant association between any nonrecommended BrS drug use and implantable cardioverter defibrillator therapy (n=20/97, odds ratio [OR], 0.7 [0.2-2.4]), mortality (n=10/270, OR, 3.4 [0.7-19.6]), or the combined end point (n=38/270, OR, 1.7 [0.8-3.7]) was identified. Conclusions One in 3 patients with BrS were treated with a nonrecommended BrS drug after BrS diagnosis, and a BrS diagnosis did not change prescription patterns. More awareness of nonrecommended drug use among patients with BrS is needed.

Extended anticoagulation for venous thromboembolism: A survey of the American Venous Forum and the European Venous Forum.

OBJECTIVE: Extended anticoagulation therapy should always be considered after standard treatment of an unprovoked episode of venous thromboembolism (VTE). It can also be considered for selected patients with provoked VTE. However, the evidence-based protocols suggested by some clinical guidelines and risk assessment tools to guide this practice are limited and ambiguous. The goal of the present survey research was to analyze current practices in applying extended anticoagulation therapy for patients with VTE among members of the American Venous Forum (AVF) and European Venous Forum (EVF). METHODS: An online survey was created by the AVF Research Committee. The survey consisted of 16 questions to identify the country of practice, specialty, experience of the participating physicians, and their clinical practice patterns in applying extended anticoagulation therapy for VTE patients. The survey was distributed via e-mail to the members of the AVF and EVF. RESULTS: A total of 144 practitioners, 48 AVF members (33%) and 96 EVF members (66%), participated in the survey. Most of the respondents identified themselves as vascular specialists with primary certification in vascular surgery (70%), vascular medicine or angiology (9%), and venous disease or phlebology (3%). Of the 144 respondents, 72% believed that the risk of VTE recurrence will generally overweigh the risk of bleeding for patients with unprovoked VTE. Extended anticoagulation therapy might be used by 97% of providers. Different patterns in real world clinical practice were identified. More than one half of the practitioners estimated the VTE recurrence and bleeding risk subjectively. The antithrombotic drugs most commonly used for secondary prophylaxis were rivaroxaban, apixaban, warfarin, dabigatran, and aspirin, in decreasing order of frequency. Among the reasons selected for not regularly considering extended anticoagulation therapy were the lack of specific clinical practice guidelines (24%), lack of reported evidence (9%), and absence of valid VTE and/or bleeding risk prediction calculators (8%). Twelve participants (8%) stated that extended anticoagulation therapy would not be beneficial for most patients with VTE. Ten participants (7%) indicated that prescribing extended anticoagulation therapy was outside the scope of their specialty. CONCLUSIONS: Different practice patterns exist regarding extending anticoagulation therapy beyond the standard treatment for patients with VTE. Major gaps in knowledge remain a serious challenge at least partially explaining the inaccuracy and inconsistency in long-term VTE management. Appropriately designed studies are needed to evaluate risk stratification tools when contemporary best medical therapy is used, accurately predict VTE recurrence and its long-term outcomes, and tailor safe and effective secondary prophylaxis.

ß-blocker adherence among patients with congenital long QT syndrome: a nationwide study.

AIM: ß-blockers are the first line of treatment in patients with congenital long QT syndrome (cLQTS) (class I or II recommendation) in order to prevent malignant arrhythmias. Hence, we examined long-term ß-blocker adherence and associated risk factors among patients with cLQTS. METHODS AND RESULTS: Danish patients with cLQTS claiming a prescription for any ß-blocker after their cLQTS diagnosis were identified using data from nationwide registries and specialized inherited cardiac disease clinics (1995-2017). Patients were followed for up to 5 years. Treatment breaks >60 days were assessed (i.e. proxy for reduced adherence). Multivariable Cox regression was used to identify risk factors associated with breaks of >60 days in ß-blocker treatment. Overall, 500 out of 633 (79%) patients with cLQTS claimed at least one prescription for any ß-blocker after cLQTS diagnosis. During follow-up, 38.4% had a treatment break. Risk factors significantly associated with treatment breaks were implantable cardioverter defibrillator (ICD) [hazard ratio (HR) = 1.65, 95% confidence interval (CI): 1.08-2.53], ß-blocker side effects (HR = 2.69, 95% CI: 1.75-4.13), and psychiatric disease (HR = 1.63, 95% CI: 1.04-2.57). In contrast, patients presenting with ventricular tachycardia/syncope as cLQTS disease manifestation were less likely to have a treatment break compared with asymptomatic patients (HR = 0.55, 95% CI: 0.33-0.92). CONCLUSION: Reduced ß-blocker adherence was common with more than a third of patients having a treatment break >60 days after cLQTS diagnosis. Patients with psychiatric disease, self-reported ß-blocker side effects, and an ICD were more likely to display reduced adherence, whereas a severe cLQTS disease manifestation was associated with optimal ß-blocker adherence.

Wireless Single-Lead ECG Monitoring to Detect New-Onset Postoperative Atrial Fibrillation in Patients After Major Noncardiac Surgery: A Prospective Observational Study.

BACKGROUND: New-onset postoperative atrial fibrillation (POAF) is associated with several cardiovascular complications and higher mortality. Several pathophysiological processes such as hypoxia can trigger POAF, but these are sparsely elucidated, and POAF is often asymptomatic. In patients undergoing major gastrointestinal cancer surgery, we aimed to describe the frequency of POAF as automatically estimated and detected via wireless repeated sampling monitoring and secondarily to describe the association between preceding vital sign deviations and POAF. METHOD: Patients ≥60 years of age undergoing major gastrointestinal cancer surgery were continuously monitored for up to 4 days postoperatively. Electrocardiograms were obtained every minute throughout the monitoring period. Clinical staff were blinded to all measurements. As for the primary outcome, POAF was defined as 30 consecutive minutes or more detected by a purpose-built computerized algorithm and validated by cardiologists. The primary exposure variable was any episode of peripheral oxygen saturation (Spo2) <85% for >5 consecutive minutes before POAF. RESULTS: A total of 30,145 hours of monitoring was performed in 398 patients, with a median of 92 hours per patient (interquartile range [IQR], 54-96). POAF was detected in 26 patients (6.5%; 95% confidence interval [CI], 4.5-9.4) compared with 14 (3.5%; 95% CI, 1.94-5.83) discovered by clinical staff in the monitoring period. POAF was followed by 9.4 days hospitalization (IQR, 6.5-16) versus 6.5 days (IQR, 2.5-11) in patients without POAF. Preceding episodes of Spo2 <85% for >5 minutes (OR, 1.02; 95% CI, 0.24-4.00; P = .98) or other vital sign deviations were not significantly associated with POAF. CONCLUSIONS: New-onset POAF occurred in 6.5% (95% CI, 4.5-9.4) of patients after major gastrointestinal cancer surgery, and 1 in 3 cases was not detected by the clinical staff (35%; 95% CI, 17-56). POAF was not preceded by vital sign deviations.

Association between length of proestrus, follicular size, estrus behavior, and pregnancy rate in beef heifers subjected to fixed-time artificial insemination.

This study evaluated the relationship between proestrus length and follicular size, estrous behavior, and pregnancy rate in Bos taurus beef heifers subjected to fixed-time artificial insemination (FTAI). A total of 911 heifers received a synchronization treatment protocol for FTAI (J-Synch) consisting of an intravaginal progesterone device for 6 d, estradiol benzoate at the time of device insertion cloprostenol sodium and eCG at device removal and GnRH at the time of FTAI. The presence or absence of a corpus luteum (CL) was determined by ultrasonography at device insertion and all heifers were tail painted at device removal for estrus detection at the time of FTAI. For the establishment of different periods of proestrus length (i.e., interval from device removal to FTAI), GnRH was administered i.m. at 48 h (n = 308), 60 h (n = 290) or 72 h (n = 313) after device removal. The diameter of the largest follicle at the time of GnRH administration was determined by ultrasonography, expression of estrous was determined by percentage of tail paint removal, and FTAI was performed at the time of GnRH administration in all heifers. The diameter of the largest follicle was greater when GnRH/FTAI was performed at 72 or 60 h (12.9 ± 0.2 mm and 12.8 ± 0.1 mm, respectively) than at 48 h (12.2 ± 0.1 mm, P < 0.05). The proportion of heifers in estrus tended to be greater when GnRH/FTAI was performed at 72 h (77.0%, 137/178) than at 48 h (68.2%, 122/179; P = 0.06), and intermediate at 60 h (71.4%, 120/168). Pregnancy rate tended to be greater in heifers with the longest (72 h: 70.0%, 219/313) than the shortest (48 h: 63.6%, 196/308; P < 0.1) proestrus length, while 60 h proestrus length was intermediate (63.1%, 183/290; P= NS). Pregnancy rate was affected by the presence of a CL at device insertion (71.3%, 352/494 in heifers with a CL, vs. 59.0%, 246/417 for those without a CL; P < 0.01). For those heifers bearing a CL, pregnancy rate was greater in heifers with a 72 h proestrus length (77.0%, 134/174) than with 48 or 60 h proestrus length (67.7%, 107/158 and 68.5%, 111/162; respectively; P < 0.05). In heifers without a CL, proestrus length did not affect pregnancy rate. In summary, extending proestrus length by delaying the interval from device removal to GnRH/FTAI from 48 to 72 h, was associated with a greater diameter of the preovulatory follicle, greater proportion of heifers expressing estrus at the time of FTAI, and greater pregnancy rate in cycling beef heifers.

Sudden unexplained death versus nonautopsied possible sudden cardiac death: Findings in relatives.

BACKGROUND: International guidelines recommend work-up of relatives to autopsy negative sudden cardiac death victims, denoted as sudden unexplained death (SUD) and nonautopsied possible sudden cardiac death (pSCD) victims. This study assesses and compare baseline characteristics and clinical outcome at initial evaluation and during follow-up of relatives to SUD and pSCD victims. METHODS: We retrospectively included data from systematic screening and routine follow-up of first-degree relatives to SUD and pSCD victims referred to our Unit for Inherited Cardiac Diseases, Copenhagen, 2005-2018. Victims with an antemortem known inherited cardiac disease were excluded. RESULTS: We included 371 first-degree relatives from 187 families (120 SUD, 67 pSCD): 276 SUD relatives (age 33 ± 18 years, 54% men) and 95 pSCD relatives (age 40 ± 15 years, 51% men). The diagnostic yields of inherited cardiac diseases in SUD and pSCD families were 16% and 13%, respectively (p = .8). The diagnoses in SUD families were mainly channelopathies (68%), whereas pSCD families were equally diagnosed with cardiomyopathies, channelopathies, and premature ischemic heart disease. Ninety-three percent of diagnosed families were diagnosed at initial evaluation and 7% during follow-up (5.4 ± 3.3 years). During follow-up 34% of relatives with a diagnosed inherited cardiac disease had an arrhythmic event, compared to 5% of relatives without established diagnosis (p < .0001). CONCLUSIONS: Channelopathies dominated in SUD families whereas a broader spectrum of inherited diseases was diagnosed in pSCD families. Most affected relatives were diagnosed at initial evaluation. The event rate was low in relatives without an established diagnosis. Long-term clinical follow-up may not be warranted in all relatives with normal baseline-findings.

Comparing Seizure-Related Death and Suicide in Younger Adults with Epilepsy.

Younger adults with epilepsy have an increased mortality. Some deaths are seizure-related, for example, sudden unexpected death in epilepsy (SUDEP), whereas others, for example, suicide, have multiple causes, including adverse effects of the treatment on mood. In this retrospective population-based study of all Danish persons with epilepsy aged 18 to 49 years during 2007 to 2009 we evaluated the risk of death from seizures and suicide. SUDEP comprised 82.7% of all seizure-related death. Younger adults with epilepsy had an 8.3-fold increased risk of death from seizure-related causes compared with suicide. This underpins the importance of effective seizure control in preventing premature death. ANN NEUROL 2021;90:983-987.

Sudden unexpected death in epilepsy in persons younger than 50 years: A retrospective nationwide cohort study in Denmark.

OBJECTIVE: Persons with epilepsy have an increased mortality including a high risk of sudden unexplained death (SUD), also referred to as sudden unexpected death in epilepsy (SUDEP). We aimed to evaluate the risk of SUDEP in comparison to other causes of death and the risk of SUD in persons with and without epilepsy. METHODS: We undertook a retrospective population-based cohort study of all Danish citizens with and without epilepsy aged 1-49 years during 2007-2009. All deaths in the population were evaluated, and all cases of SUD identified. Primary causes of death in persons with epilepsy were evaluated independently by three neurologists and one neuropediatrician, using the unified SUDEP criteria. RESULTS: The three most frequent causes of death in persons with epilepsy were cancer (2.38 per 1000 person-years), SUDEP (1.65 per 1000 person-years), and pneumonia (1.09 per 1000 person-years) compared with cancer (.17 per 1000 person-years), accident-related deaths (.14 per 1000 person-years), and cardiovascular disease (.09 per 1000 person-years) in persons without epilepsy. Considering definite, definite plus, and probable cases, the SUDEP incidence was .27 per 1000 person-years (95% confidence interval [CI] = .11-.64) in children aged 1-17 years and 1.21 per 1000 person-years (95% CI = .96-1.51) in adults aged 18-49 years. Adjusted for age and sex, persons with epilepsy younger than 50 years had a 10.8-fold (95% CI = 9.97-11.64, p < .0001) increased all-cause mortality and a 34.4-fold (95% CI = 23.57-50.28, p < .0001) increased risk of SUD compared with persons without epilepsy. SUDEP accounted for 23.3% of all SUD. SIGNIFICANCE: This nationwide study of all deaths in persons with epilepsy younger than 50 years found a lower SUDEP risk in children compared with adults, and that epilepsy was a major risk factor for SUD in the background population. This underlines the importance of addressing risk factors for SUDEP to prevent premature death.

Familial Evaluation in Idiopathic Ventricular Fibrillation: Diagnostic Yield and Significance of J Wave Syndromes.

[Figure: see text].

Iron-Phosphorus Feedbacks Drive Multidecadal Oscillations in Baltic Sea Hypoxia.

Hypoxia has occurred intermittently in the Baltic Sea since the establishment of brackish-water conditions at ∼8,000 years B.P., principally as recurrent hypoxic events during the Holocene Thermal Maximum (HTM) and the Medieval Climate Anomaly (MCA). Sedimentary phosphorus release has been implicated as a key driver of these events, but previous paleoenvironmental reconstructions have lacked the sampling resolution to investigate feedbacks in past iron-phosphorus cycling on short timescales. Here we employ Laser Ablation (LA)-ICP-MS scanning of sediment cores to generate ultra-high resolution geochemical records of past hypoxic events. We show that in-phase multidecadal oscillations in hypoxia intensity and iron-phosphorus cycling occurred throughout these events. Using a box model, we demonstrate that such oscillations were likely driven by instabilities in the dynamics of iron-phosphorus cycling under preindustrial phosphorus loads, and modulated by external climate forcing. Oscillatory behavior could complicate the recovery from hypoxia during future trajectories of external loading reductions.

Cause-specific mortality in children and young adults with diabetes mellitus: A Danish nationwide cohort study.

AIMS: Persons with diabetes mellitus have increased all-cause mortality compared with the general population. Nationwide studies on causes of death and mortality among young persons with diabetes mellitus are sparse. The aim of this study was to examine all-cause and cause-specific mortality in children and young adults with and without diabetes. METHODS AND RESULTS: The study population consisted of all persons in Denmark aged 1-35 years in 2000-2009 and 36-49 years in 2007-2009, which equals 27.1 million person-years. All 14,294 deaths in the 10-year period were included and cause of death was established based on information from autopsy reports and death certificates. The Danish Register of Medicinal Product Statistics was used to identify persons with type 1 diabetes and type 2 diabetes. During the study period, which included 153,070 diabetic person-years, 669 (5% of all deceased) persons with diabetes mellitus died, of which 70% had type 1 and 30% had type 2 diabetes. Persons with diabetes mellitus had an all-cause mortality rate (ASMR) of 327 per 100,000 person-years compared with 74 per 100,000 person-years among persons without diabetes mellitus (ASMR ratio 4, p < 0.001). The leading cause of death among persons with diabetes mellitus was cardiac diseases (n = 230, 34%) with an ASMR ratio of 8 (95% confidence interval 6-9). CONCLUSIONS: Young persons with diabetes mellitus had four-fold increased all-cause mortality and eight-fold increased cardiovascular mortality compared with persons without diabetes mellitus. Focus on cardiovascular risk monitoring and management among young persons with diabetes mellitus is warranted to prevent premature death in diabetes mellitus.