Holocene deglaciation drove rapid genetic diversification of Atlantic walrus.

Rapid global warming is severely impacting Arctic ecosystems and is predicted to transform the abundance, distribution and genetic diversity of Arctic species, though these linkages are poorly understood. We address this gap in knowledge using palaeogenomics to examine how earlier periods of global warming influenced the genetic diversity of Atlantic walrus (Odobenus rosmarus rosmarus), a species closely associated with sea ice and shallow-water habitats. We analysed 82 ancient and historical Atlantic walrus mitochondrial genomes (mitogenomes), including now-extinct populations in Iceland and the Canadian Maritimes, to reconstruct the Atlantic walrus' response to Arctic deglaciation. Our results demonstrate that the phylogeography and genetic diversity of Atlantic walrus populations was initially shaped by the last glacial maximum (LGM), surviving in distinct glacial refugia, and subsequently expanding rapidly in multiple migration waves during the late Pleistocene and early Holocene. The timing of diversification and establishment of distinct populations corresponds closely with the chronology of the glacial retreat, pointing to a strong link between walrus phylogeography and sea ice. Our results indicate that accelerated ice loss in the modern Arctic may trigger further dispersal events, likely increasing the connectivity of northern stocks while isolating more southerly stocks putatively caught in small pockets of suitable habitat.

An evolutionarily distinct ringed seal in the Ilulissat Icefjord.

The Earth's polar regions are low rates of inter- and intraspecific diversification. An extreme mammalian example is the Arctic ringed seal (Pusa hispida hispida), which is assumed to be panmictic across its circumpolar Arctic range. Yet, local Inuit communities in Greenland and Canada recognize several regional variants; a finding supported by scientific studies of body size variation. It is however unclear whether this phenotypic variation reflects plasticity, morphs or distinct ecotypes. Here, we combine genomic, biologging and survey data, to document the existence of a unique ringed seal ecotype in the Ilulissat Icefjord (locally 'Kangia'), Greenland; a UNESCO World Heritage site, which is home to the most productive marine-terminating glacier in the Arctic. Genomic analyses reveal a divergence of Kangia ringed seals from other Arctic ringed seals about 240 kya, followed by secondary contact since the Last Glacial Maximum. Despite ongoing gene flow, multiple genomic regions appear under strong selection in Kangia ringed seals, including candidate genes associated with pelage coloration, growth and osmoregulation, potentially explaining the Kangia seal's phenotypic and behavioural uniqueness. The description of 'hidden' diversity and adaptations in yet another Arctic species merits a reassessment of the evolutionary processes that have shaped Arctic diversity and the traditional view of this region as an evolutionary freezer. Our study highlights the value of indigenous knowledge in guiding science and calls for efforts to identify distinct populations or ecotypes to understand how these might respond differently to environmental change.

Origin and expansion of the world's most widespread pinniped: Range-wide population genomics of the harbour seal (Phoca vitulina).

The harbour seal (Phoca vitulina) is the most widely distributed pinniped, occupying a wide variety of habitats and climatic zones across the Northern Hemisphere. Intriguingly, the harbour seal is also one of the most philopatric seals, raising questions as to how it colonized its current range. To shed light on the origin, remarkable range expansion, population structure and genetic diversity of this species, we used genotyping-by-sequencing to analyse ~13,500 biallelic single nucleotide polymorphisms from 286 individuals sampled from 22 localities across the species' range. Our results point to a Northeast Pacific origin of the harbour seal, colonization of the North Atlantic via the Canadian Arctic, and subsequent stepping-stone range expansions across the North Atlantic from North America to Europe, accompanied by a successive loss of genetic diversity. Our analyses further revealed a deep divergence between modern North Pacific and North Atlantic harbour seals, with finer-scale genetic structure at regional and local scales consistent with strong philopatry. The study provides new insights into the harbour seal's remarkable ability to colonize and adapt to a wide range of habitats. Furthermore, it has implications for current harbour seal subspecies delineations and highlights the need for international and national red lists and management plans to ensure the protection of genetically and demographically isolated populations.

Emergence and radiation of distemper viruses in terrestrial and marine mammals.

Canine distemper virus (CDV) and phocine distemper virus (PDV) are major pathogens to terrestrial and marine mammals. Yet little is known about the timing and geographical origin of distemper viruses and to what extent it was influenced by environmental change and human activities. To address this, we (i) performed the first comprehensive time-calibrated phylogenetic analysis of the two distemper viruses, (ii) mapped distemper antibody and virus detection data from marine mammals collected between 1972 and 2018, and (iii) compiled historical reports on distemper dating back to the eighteenth century. We find that CDV and PDV diverged in the early seventeenth century. Modern CDV strains last shared a common ancestor in the nineteenth century with a marked radiation during the 1930s-1950s. Modern PDV strains are of more recent origin, diverging in the 1970s-1980s. Based on the compiled information on distemper distribution, the diverse host range of CDV and basal phylogenetic placement of terrestrial morbilliviruses, we hypothesize a terrestrial CDV-like ancestor giving rise to PDV in the North Atlantic. Moreover, given the estimated timing of distemper origin and radiation, we hypothesize a prominent role of environmental change such as the Little Ice Age, and human activities like globalization and war in distemper virus evolution.

Longitudinal analysis of pinnipeds in the northwest Atlantic provides insights on endemic circulation of phocine distemper virus.

Phocine distemper virus (PDV) is a morbillivirus that circulates within pinnipeds in the North Atlantic. PDV has caused two known unusual mortality events (UMEs) in western Europe (1988, 2002), and two UMEs in the northwest Atlantic (2006, 2018). Infrequent cross-species transmission and waning immunity are believed to contribute to periodic outbreaks with high mortality in western Europe. The viral ecology of PDV in the northwest Atlantic is less well defined and outbreaks have exhibited lower mortality than those in western Europe. This study sought to understand the molecular and ecological processes underlying PDV infection in eastern North America. We provide phylogenetic evidence that PDV was introduced into northwest Atlantic pinnipeds by a single lineage and is now endemic in local populations. Serological and viral screening of pinniped surveillance samples from 2006 onward suggest there is continued circulation of PDV outside of UMEs among multiple species with and without clinical signs. We report six full genome sequences and nine partial sequences derived from harbour and grey seals in the northwest Atlantic from 2011 through 2018, including a possible regional variant. Work presented here provides a framework towards greater understanding of how recovering populations and shifting species may impact disease transmission.

Speciation in the deep: genomics and morphology reveal a new species of beaked whale Mesoplodon eueu.

The deep sea has been described as the last major ecological frontier, as much of its biodiversity is yet to be discovered and described. Beaked whales (ziphiids) are among the most visible inhabitants of the deep sea, due to their large size and worldwide distribution, and their taxonomic diversity and much about their natural history remain poorly understood. We combine genomic and morphometric analyses to reveal a new Southern Hemisphere ziphiid species, Ramari's beaked whale, Mesoplodon eueu, whose name is linked to the Indigenous peoples of the lands from which the species holotype and paratypes were recovered. Mitogenome and ddRAD-derived phylogenies demonstrate reciprocally monophyletic divergence between M. eueu and True's beaked whale (M. mirus) from the North Atlantic, with which it was previously subsumed. Morphometric analyses of skulls also distinguish the two species. A time-calibrated mitogenome phylogeny and analysis of two nuclear genomes indicate divergence began circa 2 million years ago (Ma), with geneflow ceasing 0.35-0.55 Ma. This is an example of how deep sea biodiversity can be unravelled through increasing international collaboration and genome sequencing of archival specimens. Our consultation and involvement with Indigenous peoples offers a model for broadening the cultural scope of the scientific naming process.

Risk factors and lifelong impact of community-acquired pneumonia in congenital heart disease.

INTRODUCTION: The prevalence of congenital heart disease (CHD) in adults is rising necessitating a greater understanding of acquired diseases such as community-acquired pneumonia, which remains a leading cause of age-related mortality and morbidity in the general population. We hypothesise that the CHD population, given cardiopulmonary mechanics and altered immune function, bears a uniquely high risk for pneumonia-related hospitalisations and mortality. METHODS: A countrywide cohort study was performed to calculate the relative risk and cumulative incidence of pneumonia hospitalisations and resultant 30-day mortality amongst the adult CHD population, matched 1:10 with non-CHD persons by gender, age, and adjusted for comorbidities. Cox proportional hazard regression quantified the impact of CHD severity and extracardiac defects. RESULTS: The CHD cohort includes 17,162 adults. The majority demonstrate mild/moderate CHD complexity. The cumulative incidence of pneumonia hospitalisation was higher for adults with CHD (hazard ratio 1.90; 95% confidence interval: 1.74-2.06) than the comparison cohort. This risk was increased for those with extracardiac defects or a syndrome (hazard ratio: 4.34; 95% confidence interval: 3.39-5.54). Additionally, CHD individuals with severe/univentricular subtypes demonstrate a heightened risk compared to the non-CHD cohort (hazard ratio: 2.35; 95% confidence interval: 1.94-2.84), as well as compared to those with mild/moderate CHD (hazard ratio: 1.28; 95% confidence interval: 1.07-1.53). In addition, pneumonia hospitalisation mortality was elevated above the comparison population with a 30-day mortality rate ratio of 1.31 (95% confidence interval: 1.00-1.73). CONCLUSION: Adults with CHD are at elevated risk of pneumonia hospitalisations and pneumonia-associated mortality. This risk is further elevated in those with severe CHD and extracardiac defects.

Disappearance of Icelandic Walruses Coincided with Norse Settlement.

There is a growing body of evidence demonstrating the impacts of human arrival in new "pristine" environments, including terrestrial habitat alterations and species extinctions. However, the effects of marine resource utilization prior to industrialized whaling, sealing, and fishing have largely remained understudied. The expansion of the Norse across the North Atlantic offers a rare opportunity to study the effects of human arrival and early exploitation of marine resources. Today, there is no local population of walruses on Iceland, however, skeletal remains, place names, and written sources suggest that walruses existed, and were hunted by the Norse during the Settlement and Commonwealth periods (870-1262 AD). This study investigates the timing, geographic distribution, and genetic identity of walruses in Iceland by combining historical information, place names, radiocarbon dating, and genomic analyses. The results support a genetically distinct, local population of walruses that went extinct shortly after Norse settlement. The high value of walrus products such as ivory on international markets likely led to intense hunting pressure, which-potentially exacerbated by a warming climate and volcanism-resulted in the extinction of walrus on Iceland. We show that commercial hunting, economic incentives, and trade networks as early as the Viking Age were of sufficient scale and intensity to result in significant, irreversible ecological impacts on the marine environment. This is to one of the earliest examples of local extinction of a marine species following human arrival, during the very beginning of commercial marine exploitation.

Perturbation drives changing metapopulation dynamics in a top marine predator.

Metapopulation theory assumes a balance between local decays/extinctions and local growth/new colonisations. Here we investigate whether recent population declines across part of the UK harbour seal range represent normal metapopulation dynamics or are indicative of perturbations potentially threatening the metapopulation viability, using 20 years of population trends, location tracking data (n = 380), and UK-wide, multi-generational population genetic data (n = 269). First, we use microsatellite data to show that two genetic groups previously identified are distinct metapopulations: northern and southern. Then, we characterize the northern metapopulation dynamics in two different periods, before and after the start of regional declines (pre-/peri-perturbation). We identify source-sink dynamics across the northern metapopulation, with two putative source populations apparently supporting three likely sink populations, and a recent metapopulation-wide disruption of migration coincident with the perturbation. The northern metapopulation appears to be in decay, highlighting that changes in local populations can lead to radical alterations in the overall metapopulation's persistence and dynamics.

DNA preserved in jetsam whale ambergris.

Jetsam ambergris, found on beaches worldwide, has always been assumed to originate as a natural product of sperm whales (Physeteroidea). However, only indirect evidence has ever been produced for this, such as the presence of whale prey remains in ambergris. Here, we extracted and analysed DNA sequences from jetsam ambergris from beaches in New Zealand and Sri Lanka, and sequences from ambergris of a sperm whale beached in The Netherlands. The lipid-rich composition of ambergris facilitated high preservation-quality of endogenous DNA, upon which we performed shotgun Illumina sequencing. Alignment of mitochondrial and nuclear genome sequences with open-access reference data for multiple whale species confirms that all three jetsam samples derived originally from sperm whales (Physeter macrocephalus). Shotgun sequencing here also provides implications for metagenomic insights into ambergris-preserved DNA. These results demonstrate significant implications for elucidating the origins of jetsam ambergris as a prized natural product, and also for the understanding of sperm whale metabolism and diet, and the ecological mechanisms underlying these coproliths.

Using ecosystem-services assessments to determine trade-offs in ecosystem-based management of marine mammals.

The goal of ecosystem-based management (EBM) is to support a sustainable and holistic multisectored management approach, and is recognized in a number of international policy frameworks. However, it remains unknown how these goals should be linked to assessments and management plans for marine fauna, such as mammals and fish stocks. It appears particularly challenging to carry out trade-off analyses of various ocean uses without a framework that integrates knowledge of environmental, social, and economic benefits derived from nonstationary marine fauna. We argue this gap can be filled by applying a version of the ecosystem-service approach at the population level of marine fauna. To advance this idea, we used marine mammals as a case study to demonstrate what indicators could operationalize relevant assessments and deliver an evidence base for the presence of ecosystem services and disservices derived from marine mammals. We found indicators covering common ecosystem service categories feasible to apply; examples of indicator data are already available in the literature for several populations. We encourage further exploration of this approach for application to marina fauna and biodiversity management, with the caveat that conceptual tensions related to the use of the ecosystem service concept itself needs to be addressed to ensure acceptance by relevant stakeholders.

Uso de Evaluaciones de Servicios Ambientales para Determinar las Compensaciones en el Manejo de Mamíferos Marinos Basado en Ecosistemas Resumen El objetivo del manejo basado en ecosistemas (EBM) es respaldar una estrategia de manejo multisectorial sustentable y holística, objetivo que es reconocido dentro de varias políticas de marcos de trabajo internacional. Sin embargo, todavía desconocemos cómo deben vincularse este objetivo con las evaluaciones y los planes de manejo de la fauna marina, como los mamíferos y las poblaciones ícticas. Actualmente, parece un reto realizar los análisis de las compensaciones de varios usos oceánicos sin un marco de trabajo que integre el conocimiento sobre los beneficios ambientales, sociales y económicos derivados de la fauna marina no estacionaria. Discutimos que este vacío puede completarse con la aplicación de una versión de la estrategia de servicio ambiental a nivel poblacional para la fauna marina. Para impulsar esta idea usamos mamíferos marinos como estudio de caso para demostrar cuáles indicadores podrían poner en práctica evaluaciones relevantes y entregar una base de evidencias para la presencia de servicios y perjuicios ambientales derivados de los mamíferos marinos. Descubrimos indicadores que cubren las categorías de servicios ambientales comunes cuya aplicación es factible; los ejemplos de datos indicadores ya se encuentran disponibles en la literatura para varias de las poblaciones. Alentamos una exploración más profunda de esta estrategia para su aplicación en la fauna marina y el manejo de biodiversidad, bajo advertencia de que las tensiones conceptuales relacionadas con el uso del concepto de servicio ambiental necesitan ser tratadas para asegurar la aceptación por parte de los actores relevantes.

Atopic dermatitis and risk of atrial fibrillation or flutter: A 35-year follow-up study.

BACKGROUND: Atopic dermatitis is characterized by chronic inflammation, which is a risk factor for atrial fibrillation. OBJECTIVE: To examine the association between hospital-diagnosed atopic dermatitis and atrial fibrillation. METHODS: Using linked population-based Danish registries, we identified persons with an inpatient or outpatient hospital diagnosis of atopic dermatitis during 1977-2013 and a comparison cohort individually matched to the atopic dermatitis cohort. We followed cohorts until death, emigration, atrial fibrillation diagnosis, or end of study (January 1, 2013). We compared 35-year risk of atrial fibrillation and estimated hazard ratios with 95% confidence intervals using Cox regression, adjusting for birth year and sex. We validated 100 atopic dermatitis diagnoses from a dermatologic department through medical record review. RESULTS: We included 13,126 persons with atopic dermatitis and 124,211 comparators and followed them for a median of 19.3 years. The 35-year risk of atrial fibrillation was 0.81% and 0.67%, respectively. The positive predictive value of atopic dermatitis diagnoses was 99%. The hazard ratio was 1.2 (95% confidence interval 1.0-1.6) and remained increased after adjusting for various atrial fibrillation risk factors. LIMITATIONS: Analyses were limited to persons with moderate-to-severe atopic dermatitis, and we had no lifestyle data. CONCLUSION: Patients with hospital-diagnosed atopic dermatitis have a 20% increased long-term risk of atrial fibrillation, but the absolute risk remains low.

Gain-of-function mutation in the voltage-gated potassium channel gene KCNQ1 and glucose-stimulated hypoinsulinemia - case report.

BACKGROUND: The voltage-gated potassium channel Kv7.1 encoded by KCNQ1 is located in both cardiac myocytes and insulin producing beta cells. Loss-of-function mutations in KCNQ1 causes long QT syndrome along with glucose-stimulated hyperinsulinemia, increased C-peptide and postprandial hypoglycemia. The KCNE1 protein modulates Kv7.1 in cardiac myocytes, but is not expressed in beta cells. Gain-of-function mutations in KCNQ1 and KCNE1 shorten the action potential duration in cardiac myocytes, but their effect on beta cells and insulin secretion is unknown. CASE PRESENTATION: Two patients with atrial fibrillation due to gain-of-function mutations in KCNQ1 (R670K) and KCNE1 (G60D) were BMI-, age-, and sex-matched to six control participants and underwent a 6-h oral glucose tolerance test (OGTT). During the OGTT, the KCNQ1 gain-of-function mutation carrier had 86% lower C-peptide response after glucose stimulation compared with matched control participants (iAUC360min = 34 pmol/l*min VS iAUC360min = 246 ± 71 pmol/l*min). The KCNE1 gain-of-function mutation carrier had normal C-peptide levels. CONCLUSIONS: This case story presents a patient with a gain-of-function mutation KCNQ1 R670K with low glucose-stimulated C-peptide secretion, additionally suggesting involvement of the voltage-gated potassium channel KCNQ1 in glucose-stimulated insulin regulation.

Congenital Heart Disease and Risk of Central Nervous System Infections: A Nationwide Cohort Study.

Congenital heart disease (CHD) is associated with risk factors of central nervous system (CNS) infections including infective endocarditis, cardiac shunt physiology, and immune deficiencies. We aimed to investigate the risk of CNS infections in the CHD population compared to the general population. In this cohort study, we used Danish nationwide medical registries to identify individuals diagnosed with CHD at any age, born between 1977 and 2012. For each CHD individual, we matched 10 individuals on sex and birth year from the general population. Subjects were followed until first-time hospital diagnosis of CNS infection, death, emigration, or end of study. We computed cumulative incidences of CNS infections with death as a competing risk, as well as hazard ratios (HRs) with corresponding 95% confidence intervals (CIs) adjusted for birth year and sex. We identified 17,550 individuals with CHD (50% male). Among subjects with CHD, the cumulative incidence of CNS infection at age 30 years was 1.0% compared to 0.6% in the general population. The overall HR of CNS infections in CHD subjects relative to the general population was 2.1 (95% CI 1.6-2.7). The HR was 1.9 (95% CI 1.4-2.7) for mild to moderate CHD, 2.1 (95% CI 1.3-3.3) for severe CHD and 3.0 (95% CI 1.1-8.2) for univentricular physiology. The HR for CHD subjects without record of infective endocarditis was 2.0 (95% CI 1.5-2.5). The risk of CNS infections was increased among individuals with CHD compared to the general population, and the risk was not limited to individuals with infective endocarditis.

Risk of Dementia in Adults With Congenital Heart Disease: Population-Based Cohort Study.

BACKGROUND: More children with congenital heart disease (CHD) are surviving to adulthood, and CHD is associated with risk factors for dementia. We compared the risk of dementia in CHD adults to that of the general population. METHODS: In this cohort study, we used medical registries and a medical record review covering all Danish hospitals to identify adults with CHD diagnosed between 1963 and 2012. These individuals with CHD were followed from January 1, 1981, 30 years of age, or date of first CHD registration (index date for matched members of the general population cohort) until hospital diagnosis of dementia, death, emigration, or end of study (December 31, 2012). For each individual with CHD, we identified 10 members of the general population utilizing the Danish Civil Registration System matched on sex and birth year. We computed cumulative incidences and hazard ratios (HRs) of dementia, adjusting for sex and birth year. RESULTS: The cumulative incidence of dementia was 4% by 80 years of age in 10 632 adults with CHD (46% male). The overall HR comparing adults with CHD with the general population cohort was 1.6 (95% confidence interval [CI], 1.3-2.0). The HR among individuals with CHD without extracardiac defects was 1.4 (95% CI, 1.1-1.8). Adults with mild-to-moderate CHD had an HR of 1.5 (95% CI, 1.1-2.0), whereas the HR was 2.0 (95% CI, 1.2-3.3) for severe CHD, including univentricular hearts. The HR for early onset dementia (<65 years of age) was 2.6 (95% CI, 1.8-3.8), whereas the late-onset HR was 1.3 (95% CI, 1.0-1.8). CONCLUSIONS: CHD was associated with an increased risk of dementia compared with the general population, in particular for early onset dementia. Further understanding of dementia risk in the population with CHD is a potential target for future investigation.

Phylogenomic insights to the origin and spread of phocine distemper virus in European harbour seals in 1988 and 2002.

The 1988 and 2002 phocine distemper virus (PDV) outbreaks in European harbour seals Phoca vitulina are among the largest mass mortality events recorded in marine mammals. Despite its large impact on harbour seal population numbers, and 3 decades of studies, many questions regarding the spread and temporal origin of PDV remain unanswered. Here, we sequenced and analysed 7123 bp of the PDV genome, including the coding and non-coding regions of the entire P, M, F and H genes in tissues from 44 harbour seals to shed new light on the origin and spread of PDV in 1988 and 2002. The phylogenetic analyses trace the origin of the PDV strain causing the 1988 outbreak to between May 1987 and April 1988, while the origin of the strain causing the 2002 outbreak can be traced back to between June 2001 and May 2002. The analyses further point to several independent introductions of PDV in 1988, possibly linked to a southward mass immigration of harp seals in the winter and spring of 1987-1988. The vector for the 2002 outbreak is unknown, but the epidemiological analyses suggest the subsequent spread of PDV from the epicentre in the Kattegat, Denmark, to haul-out sites in the North Sea through several independent introductions.

Respiratory distress syndrome in preterm infants and risk of epilepsy in a Danish cohort.

Infant respiratory distress syndrome (IRDS) may be complicated by intracerebral hemorrhage, a known trigger of epilepsy. However, few data exist on long term epilepsy risk following IRDS. We therefore examined the association between IRDS in preterm infants and childhood epilepsy. We conducted a population-based cohort study using individual-level data linkage among nationwide registries. All infants born at 32-36 weeks of gestation in 1978-2009 were identified in the Medical Birth Registry. We identified children with IRDS and those with epilepsy using the Danish National Patient Registry. We computed the cumulative incidence of epilepsy with follow-up from birth until epilepsy, emigration, death, age 15, or December 31, 2014. We used Cox's regression analysis to compute hazard ratios comparing children with and without IRDS, adjusting for sex, birth year, gestational age, multiplicity, major malformations, and maternal age. We identified 95,026 infants, of whom 6426 (6.8%) had IRDS. The cumulative incidence of epilepsy was 3.4% by age 15 in children with IRDS and 2.1% in children without IRDS. The adjusted hazard ratio of epilepsy among children with IRDS compared to those without was 1.4 (95% CI 1.2-1.6). When we restricted the IRDS cohort to children with no simultaneous morbidities that had clinical symptoms overlapping with IRDS, the overall adjusted HR was 1.1 (95% CI 0.9-1.4). In children born preterm at 32-36 weeks' gestation, IRDS was associated with increased risk of childhood epilepsy.

Long-Term Nationwide Follow-Up Study of Simple Congenital Heart Disease Diagnosed in Otherwise Healthy Children.

BACKGROUND: Systematic follow-up is currently not recommended for patients with simple congenital heart disease; however, only a few data exist on the long-term prognosis of simple congenital heart disease. METHODS AND RESULTS: We undertook a nationwide follow-up study of a cohort of 1241 simple congenital heart disease patients, diagnosed from 1963 through 1973, in otherwise healthy children and alive at 15 years of age. We identified 10 age- and sex-matched general population controls per patient. We followed the study population through Danish public registries from the age of 15 years up to January 1, 2013 with respect to mortality, cause of death, morbidity, and medical follow-up. The patients were followed for a total of 58 422 patient-years and had a median age at the end of follow-up of 47.4 years (interquartile range, 43.5-50.9). Mortality was increased compared with the general population, both overall (adjusted hazard ratio [aHR],1.9; 95% confidence interval [CI], 1.5-2.4)] and for patients (79%) without medical follow-up (aHR, 1.7; 95% CI, 1.3-2.2). The most common cause of death (40%) was sudden unexpected death (aHR, 4.3; 95% CI, 2.9-6.5). The incidence of critical cardiac morbidity was 3.9 per 1000 patient-years with the most frequent events being an adult (re)operation and hospitalization for heart failure or ventricular tachyarrhythmia. This corresponded to an aHR of 5.7 (95% CI, 4.6-6.9) when compared with the general population. CONCLUSIONS: Patients diagnosed with simple congenital heart disease in the 1960s have substantially increased long-term mortality and cardiac morbidity compared with the general population. Further studies on the effectiveness of systematic medical follow-up programs appear warranted.

Cardiac surgery in patients with congenital heart disease is associated with acute kidney injury and the risk of chronic kidney disease.

Cardiac surgery associated-acute kidney injury (CS-AKI) occurs in 30-50% of patients undergoing surgery for congenital heart disease. Here we determine if CS-AKI is associated with chronic kidney disease (CKD) in patients with congenital heart disease. Using Danish regional population-based registries, our cohort study included patients with congenital heart disease born between 1990-2010 with first cardiac surgery between 2005 and 2010 (under 15 years of age). Utilizing in- and out-patient laboratory serum creatinine data, we identified individuals fulfilling KDIGO stages of AKI within 5 days of cardiac surgery. A unique personal identifier enabled unambiguous data linkage and virtually complete follow-up. The cumulative incidences of CKD stages 2-5 according to presence of CS-AKI were computed utilizing serum creatinine values and Pottel's formula. Using Cox regression, the corresponding hazard ratios were computed, adjusting for sex, age at first cardiac surgery, calendar period of surgery, and congenital heart disease severity. Of 382 patients with congenital heart disease undergoing cardiac surgery, 127 experienced CS-AKI within 5 days of surgery. Median follow-up was 4.9 years. The five-year cumulative incidence of CKD for patients with CS-AKI was 12% (95% confidence interval 7%-20%), significantly higher than the 3% (1%-5%) for those without CS-AKI with a significant adjusted hazard ratio of 3.8 (1.4-10.4). Thus, CS-AKI in patients with congenital heart disease is common and is associated with an increased risk for CKD.

Infants with prenatally diagnosed kidney anomalies have an increased risk of urinary tract infections.

AIM: This study estimated the urinary tract infection (UTI) risk in a nationwide cohort of infants prenatally diagnosed with parenchymal kidney anomalies compared with a comparison cohort. METHODS: A Danish population-based nationwide cohort of foetuses diagnosed with parenchymal kidney anomalies between 2007 and 2012 had previously been identified. These were compared with foetuses without kidney anomalies who were prenatally scanned the same year. Live born infants were followed from birth until the diagnosis of UTI, emigration, death or two years of age. Cumulative incidences of UTIs were computed. Mortality was estimated using the Kaplan-Meier method. RESULTS: We identified 412 foetuses with parenchymal kidney anomalies out of 362 069 who underwent ultrasound scans and 277 were born alive. The overall risk of a UTI before the age of two years was 19%, and it was 14% among infants without prenatally diagnosed co-occurring urinary tract malformations. The corresponding risk in the 4074 controls was 1%. After two years, mortality was 2.2% in infants with prenatally diagnosed parenchymal kidney anomalies and 0.2% in the controls. CONCLUSION: Infants prenatally diagnosed with parenchymal kidney anomalies had a substantially increased risk of UTI. Awareness of this increased risk may facilitate earlier diagnosis of UTIs in this population.