Danish National Research Articles

Unchanged incidence but change in treatment trends from 1996 to 2018: 23,718 humeral shaft fractures from the Danish National Patient Registry.

Humeral shaft fractures (HSF) can be treated surgically or non-surgically. National trends and distributions are sparsely reported. We present the temporal trends in epidemiology of adult HSF in Denmark, with the primary aim of reporting HSF incidences, and the secondary aim of reporting on the primary treatment management. The diagnosis (International Classification of Diseases Version 10 [ICD-10]: S42.3) and surgical procedure codes for HSF were obtained from the Danish National Patient Registry (DNPR) covering 1996-2018. The diagnosis code for HSF is validated in the DNPR with a positive predictive value of 89%. Patients aged 18 years and above were included. Surgical treatment was defined as a diagnosis of HSF combined with a surgical procedure within 3 weeks of injury. Cases without relevant registered procedures within 3 weeks were defined as nonsurgical treatment cases. 23,718 HSF (62% female) were identified in the DNPR. The overall mean incidence was 25/100,000/year and was stable over 23 years. The population above 50 years accounted for 78% of all HSF. Non-surgical treatment accounted for 87% of treatments and was stable during the study period. Temporal changes were observed regarding surgical procedures; intramedullary nailing decreased from 57% to 26% and plate osteosynthesis increased from 12% to 69%. The overall incidence for HSF remained stable from 1996 to 2018. Most cases were females aged 50 years and above. The preferred primary treatment for HSF was non-surgical for all ages. Plate osteosynthesis became more popular than intramedullary nailing over the study period.

No difference in short-term readmissions following day-case vs. one overnight stay in patients having hip and knee arthroplasty: a nationwide register study of 51,042 procedures from 2010-2020.

Day-case hip and knee arthroplasty has gained in popularity, but there are conflicting results regarding readmissions. We aimed to investigate differences in 30- and 90-day readmission rates between day-case patients and patients with a single overnight stay following primary total hip arthroplasty (THA), total knee arthroplasty (TKA), and unicompartmental knee arthroplasty (UKA). We identified day-case (DC) and overnight (ON) THA, TKA, and UKA patients, operated on between 2010 and 2020, from the Danish National Patient Register. Day-case surgery was defined as discharge on the day of surgery. Overnight readmissions within 30 or 90 days of surgery were considered readmissions. We compared readmission rates between DC and ON patients within arthroplasty types using logistic regression adjusted for patient characteristics and year of surgery. We included 29,486 THAs (1,353 DC and 28,133 ON), 15,116 TKAs (617 DC and 14,499 ON), and 6,440 UKAs (1,528 DC and 4,914 ON). The 30-day readmission rates were: DC-THA 4.4% vs. ON-THA 4.4% (adjusted odds-ratio [aOR] 1.2, 95% confidence interval [CI] 0.91-1.6), DC-TKA 4.7% vs. ON-TKA 4.4% (aOR 1.1, CI 0.69-1.5), and DC-UKA 3.0% vs. ON-UKA 3.0% (aOR 1.1, CI 0.78-1.5). Similarly, no significant differences were present between DC and ON THA, TKA, and UKA regarding 90-day readmissions or time to readmission. We found no differences in readmission rates between day-case THA, TKA, and UKA patients and patients with a single overnight stay.

Are self-reported medical conditions and medicine use from middle-aged and older adults credible? A validation study comparing Danish SHARE-data with National Health Register data

Self-reported information on medical conditions and medicine use is widely used in epidemiological research. We investigated the validity of self-reported medical conditions and medicine use from Danish participants in the Survey of Health, Ageing and Retirement in Europe. Self-reported health data were linked at individual level with the National Patient Registry and the Danish National Prescription Registry (n=5572). Agreement was assessed by kappavalue and presented as sensitivity, specificity, predictive values, and odds ratios. The agreement of self-reported medical conditions varied by type (κ=0.23-0.67), lowest for cholesterol-related diseases,highest for diabetes. Self-reported medicine use varied by medication type (κ=0.33-0.90) lowest for painkillers, highest for diabetes. Women had lower odds for self-reporting medicine use correctlybut higher odds for self-reported diseases. Higher age was associated with lower agreement, while higher education with higher agreement. Although Danish data from the Survey of Health, Ageing and Retirement in Europe on medical conditions and medicine vary, the data are valid for epidemiological use for most medicine data, and for diseases associated with hospitalizations or influencing everyday life.Caution is warranted for self-reported data from 70+ year olds and people with lower educational level.

Benign Structures. The Worldview of Danish National Poet, Pastor, and Politician N.F.S. Grundtvig (1783-1872)

This paper presents a study of the central Danish 19th-century figure N.F.S. Grundtvig (1783-1872) and his worldview. More precisely, by way of simple neural word embeddings we seek to plot Grundtvig’s worldview in attempt to tease out factors explaining for his cultural and religious success as a poet. We arrive at the conclusion that one factor for Grundtvig’s relative success could be found in his explicitly positive worldview fit for modern conditions.

Trends in congenital clubfoot prevalence and co-occurring anomalies during 1994–2021 in Denmark: a nationwide register-based study

BackgroundCongenital talipes equinovarus (clubfoot) is a common musculoskeletal anomaly, with a suspected multifactorial etiopathogenesis. Herein, we used publicly available data to ascertain liveborn infants with clubfoot delivered in Denmark during 1994–2021, and to classify co-occurring congenital anomalies, estimate annual prevalence, and compare clubfoot occurrence with maternal smoking rates, a commonly reported risk factor. Characterizing this nationwide, liveborn cohort provides a population-based resource for etiopathogenic investigations and life course surveillance.MethodsThis case-cohort study used data from the Danish National Patient Register and Danish Civil Registration System, accessed through the publicly available Danish Biobank Register, to identify 1,315,282 liveborn infants delivered during 1994–2021 in Denmark to Danish parents. Among these, 2,358 infants (65.1% male) were ascertained with clubfoot and classified as syndromic (co-occurring chromosomal, genetic, or teratogenic syndromes) and nonsyndromic (isolated or co-occurring multiple congenital anomalies [MCA]). Annual prevalence estimates and corresponding 95% confidence intervals (CIs) for children with nonsyndromic clubfoot were estimated using Poisson regression and compared with population-based, maternal annual smoking rates obtained from publicly available resources.ResultsInfants most often presented with nonsyndromic clubfoot (isolated = 88.6%; MCA = 11.4%); limb and heart anomalies were the most frequently identified MCAs. Prevalence (per 1,000 liveborn infants) was 1.52 (CI 1.45–1.58) for isolated and 0.19 (CI 0.17–0.22) for MCA clubfoot. Prevalence estimates for both isolated and MCA clubfoot remained relatively stable during the study period, despite marked decreases in population-based maternal smoking rates.ConclusionsFrom 1994 to 2021, prevalence of nonsyndromic clubfoot in Denmark was relatively stable. Reduction in population-level maternal smoking rates did not seem to impact prevalence estimates, providing some support for the suspected multifactorial etiopathogenesis of this anomaly. This nationwide, liveborn cohort, ascertained and clinically characterized using publicly available data from the Danish Biobank Register, provides a population-based clinical and biological resource for future etiopathogenic investigations and life course surveillance.

A Jacobean Draught of an 18-gun Ship in the Danish National Archives Drawn by Phineas Pett

This article discusses an early seventeenth-century draught of an 18-gun ship, which the author believes was drawn by Phineas Pett himself. This is based on handwriting comparisons, dating evidence within the draught, dimensions and armament of the ship possibly portrayed, and a possible explanation of why an English draught is now in the Danish archives.

Healthcare costs associated with opportunistically identifiable vertebral fractures.

Vertebral fractures (VFs) are often available on radiological imaging undertaken during daily clinical work, yet the healthcare cost burden of these opportunistically identifiable fractures has not previously been reported. In this study, we examine the direct healthcare costs of subjects with vertebral fractures available for identification on routine CT scans. Thoracolumbar vertebral fractures were identified from 2000 routine CT scans. Subjects with VF on the scan were matched 1:2 against subjects with no VF on the scan, and similarly in a 1:3-ratio against a general population cohort. We excluded those subjects who received treatment with osteoporosis medication(s) in the year prior to baseline. Direct healthcare costs, identified from the national Danish registers, were accrued over up to 6years of follow-up, and reported per day at risk and per year. In subjects undergoing a CT scan, costs were initially high, yet declined over time. Comparing subjects with prevalent vertebral fracture (n=321) against those subjects with no vertebral fracture (n=606), mean total healthcare costs per day at risk was numerically higher in the first three years after baseline, while healthcare costs per year were similar between the cohorts. No differences reached statistical significance. When compared to the general population cohort, costs were significantly higher in the vertebral fracture cohort. Subjects with vertebral fractures available for identification on routine CT scans incur substantially higher healthcare costs than matched subjects representing the general population, and numerically, albeit non-significantly, higher healthcare costs per day at risk in the short term, as compared to subjects with no visible VF on the CT scan.

Treatment patterns, survival, and healthcare utilisation and costs in patients with locally advanced and metastatic bladder cancer in Denmark 2015–2020

Background Treatment patterns in locally advanced and metastatic urothelial bladder cancer (La/mUBC) is changing, but little is known about current treatment patterns, survival, and costs of these patients. Our aim was to describe treatment patterns, survival, and healthcare utilisation/costs in Danish La/mUBC patients in a routine clinical care setting. Methods Registry-based nationwide cohort study including all bladder cancer patients aged 18 years or older with a La/mUBC tumour in the pathology register and a concomitant bladder cancer diagnosis in the Danish National Patient Registry in the period 2015–2020. We categorised the patients according to (1) La/mUBC at time of first bladder cancer diagnosis (de novo La/mUBC) and (2) non-invasive or localised muscle-invasive bladder cancer at time of diagnosis which had progressed to La/mUBC. All patients were included at date of pathology-confirmed La/mUBC. Follow-up ended 30 September 2022. Results We identified 1278 patients (69% men) with La/mUBC and no other previous cancer. Of these, 212 (17%) had de novo La/mUBC, while 1066 (83%) had progressed to La/mUBC. Median age was 72 years. Patients were followed for a median of 13.0 months (interquartile range 4.7;32.0). During follow-up, 651 (51%) patients started first-line treatment, of these, 285 progressed to second-line treatment, and 112 also started third-line treatment. Median survival was 13.0 months from La/mUBC diagnosis, 12.1 months from start of first-line treatment, 9.8 months from start of second-line treatment, and 8.6 months from start of third-line treatment. The mean number of days admitted to hospital was 3.47, 3.97, and 4.07 per month following initiation of first-line, second-line, and third-line treatment, respectively. Conclusion Patients with La/mUBC have a poor prognosis, and in routine clinical care only around half of the patients received systemic anti-cancer treatment suggesting an unmet need for novel treatments. The overall costs only increased slightly from first to third-line treatment.

Venous thromboembolism associated with severe dyspnoea and asthma in 102 792 adults.

The most recent guideline on acute pulmonary embolism (PE) indicates possible long-term sequelae such as dyspnoea and chronic thromboembolic pulmonary hypertension after a PE event. However, effects on lung function or asthma risk have not been evaluated in the general population. We tested whether individuals with a venous thromboembolism (VTE) encompassing PE and deep vein thrombosis (DVT) have reduced lung function, or greater risks of dyspnoea and asthma using data from 102 792 adults from the Copenhagen General Population Study. Diagnoses of PE, DVT and asthma were collected from the national Danish Patient Registry. Factor V Leiden and prothrombin G20210A gene variants were determined using TaqMan assays. Prevalences of PE, DVT and VTE were 2.2%, 3.6% and 5.2%, respectively. Individuals with VTE had forced expiratory volume in 1 s of 92% predicted compared with 96% pred in individuals without VTE (p<0.001). Individuals with VTE versus those without had adjusted OR (95% CI) for light, moderate and severe dyspnoea of 1.4 (1.2-1.6), 1.6 (1.4-1.8) and 1.7 (1.5-1.9), respectively. Individuals with VTE versus those without had an adjusted OR for asthma of 1.6 (95% CI 1.4-1.8). Factor V Leiden and prothrombin G20210A genotype also associated with increased risk of asthma (p for trend=0.002). Population-attributable fractions of severe dyspnoea and asthma due to VTE were 3.5% and 3.0%, respectively, in the population. Individuals with VTE have worse lung function and higher risks of severe dyspnoea and asthma, and may account for 3.5% and 3.0% of people with severe dyspnoea and asthma, respectively, in the general population.

Parental age at birth and biomarkers of fecundity in young Danish men.

High parental age is associated with adverse birth and genetic outcomes, but little is known about fecundity in male offspring. We investigated if high parental age at birth was associated with biomarkers of male fecundity in a large population-based sample of young men. We conducted a study of 1057 men from the Fetal Programming of Semen Quality (FEPOS) cohort, a sub-cohort of sons born 1998-2000 into the Danish National Birth Cohort. Semen characteristics and reproductive hormone concentrations were measured in samples provided by the men 2017-2019. Testis volume was determined by self-measurement. Data on the parental age was drawn from registers. Adjusted relative difference in percentage with 95% confidence intervals were estimated for each outcome according to pre-specified maternal and paternal age groups (<30 (reference), 30-34 and ≥ 35) as well as for combinations of parental age groups, using multivariable negative binomial regression models. We did not observe consistent associations between parental age and biomarkers of fecundity, although sons of mothers ≥ 35 years had lower sperm concentration (-15% (95% CI: -30, 3)) and total sperm count (-10% (95% CI: -25, 9)). The analysis with parental age combinations showed lower sperm concentration with high age of the parents (both ≥ 35 years: -27%, 95% CI: -40, -19) when compared to the reference where both parents were below 30 years. We found no strong association between higher parental age and biomarkers of fecundity in young men. However, we cannot exclude poorer semen characteristics in sons born by older mothers or with high age of both parents.

Surveillance of SARS-CoV-2 infection based on self-administered swabs, Denmark, May to July 2022: evaluation of a pilot study.

BackgroundDuring the COVID-19 pandemic, the Danish National Institute for Infectious Disease, Statens Serum Institute (SSI) developed a home-based SARS-CoV-2 surveillance system.AimsWe wanted to determine whether a cohort of individuals performing self-administered swabs for PCR at home could support surveillance of SARS-CoV-2, including detection and assessment of new variants. We also aimed to evaluate the logistical setup.MethodsFrom May to July 2022, 10,000 blood donors were invited to participate, along with their household members. Participation required performing a self-swab for 4 consecutive weeks and answering symptom questionnaires via a web app. Swabs were sent by post to SSI for PCR analysis and whole genome sequencing. After study completion, participants were asked to complete a questionnaire concerning their experience.ResultsIn total, 2,186 individuals enrolled (47.4% blood donors), and 1,333 performed self-swabbing (53.0 blood donors), of whom 48 had at least one SARS-CoV-2-positive sample. Fourteen different Omicron subvariants, primarily BA.5 subvariants, were identified by whole genome sequencing (WGS). In total, 29 of the 63 SARS-CoV-2-positive samples were taken from individuals who were asymptomatic at the time of swabbing. Participants collected 2.9 swabs on average, with varying intervals between swabs. Transmission within households was observed in only three of 25 households.ConclusionParticipants successfully performed self-swabs and answered symptom questionnaires. Also, WGS analysis of samples was possible. The system can support surveillance of respiratory pathogens and also holds potential as a diagnostic tool, easing access to test for at-risk groups, while also reducing the burden on healthcare system resources.

Long-Term Use of Benzodiazepines and Benzodiazepine-Related Drugs: A Register-Based Danish Cohort Study on Determinants and Risk of Dose Escalation.

The authors investigated the frequency and determinants of long-term use and risk of dose escalation of benzodiazepines and benzodiazepine-related drugs (benzodiazepine receptor agonists, or BZRAs). All adults ages 20-80 years living in Denmark on January 1, 2000 (N=4,297,045) were followed for redeemed prescriptions of BZRAs in the Danish National Prescription Registry from January 1, 2000, to December 31, 2020. For each drug class, we calculated long-term use for more than 1 or 7 years, and dose escalation measured as increase in dose to a level above the recommended level. Associations were examined using logistic regression. The authors identified 950,767 incident BZRA users, of whom 15% and 3% became long-term users for more than 1 or 7 years, respectively. These percentages were highest for individuals who initiated Z-drugs (17.8% and 4%). Among the 5% of BZRA users who had at least 3 years of continuous use, there was no indication of dose escalation, as the median dose remained relatively stable. However, 7% (N=3,545) of BZRA users escalated to doses above the recommended level. Psychiatric comorbidity, especially substance use disorder, was associated with higher risk of long-term use and dose escalation. A limited portion of the population that received BZRA prescriptions were classified as continuous users, and only a small proportion of this group escalated to doses higher than those recommended in clinical guidelines. Thus, this study does not, under the current regulations, support the belief that BZRA use frequently results in long-term use or dose escalation.

Impact of prior cancer diagnosis on pancreatic cancer outcomes: A Danish Nationwide, population-based Cohort study

BackgroundThe overall survival of pancreatic cancer (PC) remains low, underlining the need of further research to improve PC directed therapy. Some patients with PC may have experienced a prior cancer, refraining them from inclusion in clinical trials, despite not knowing the precise effect of a prior cancer on disease course of PC. ObjectiveTo examine the influence of prior cancer on the disease course in patients with PC. MethodsWe conducted a cohort study including Danish patients diagnosed with PC between 2004 and 2020 crosslinking data from the Danish Cancer Registry, the Danish National Patient Registry among several other databases. Using the Kaplan-Meier estimator, we calculated the overall and American Joint Committee on Cancer (AJCC) disease stage stratified survival, comparing patients with and without prior cancer. Furthermore, using inverse probability of treatment weighting (IPTW), we presented a covariate-adjusted model of the average treatment effect in the treated (ATT) of prior cancer on the overall PC survival and stratified for AJCC disease stage. ResultsWe included 11,147 patients diagnosed with PC, of which 906 (8.1%) had a prior cancer. Comparing patients with and without prior cancer, the IPTW-adjusted survival, indicated a slightly better survival (ATT: 1.5 months; 95% CI: 0.7; 2.2 months). After stratifying by PC tumor stage, the difference was restricted to patients with stage IV PC disease (ATT: 1.1 months; 95% CI: 0.5; 1.7 months). Patients with prior cancer were slightly less prone to present with stage IV PC disease and were more likely to not receive active treatment compared with patients without prior cancer. ConclusionPrior cancer was associated with a slightly better survival in patients with PC, but only in patients with stage IV PC disease. This is likely explained by lead time bias.

Amyotrophic lateral sclerosis survival and occupational lead exposure in the Danish National Patient Registry

Amyotrophic lateral sclerosis survival and occupational lead exposure in the Danish National Patient Registry

Preoperative intravenous iron treatment – a cohort study on colorectal cancer recurrence

BackgroundIntravenous (i.v.) iron treatment has been speculated to increase the malignant potential of colorectal malignancies but also to enhance the immune systems potential to fight the invasive tumor. Clinical data however is very limited. We investigate if preoperative i.v. iron treatment is associated with colorectal cancer (CRC) recurrence. MethodsRetrospective cohort study on surgical CRC patients with iron deficiency anemia (1st March 2013 - 31st December 2019). Patients were grouped based on whether they had received preoperative treatment with i.v. iron. Local data was combined with data from the National Danish Health registries to identify recurrences, death, and emigration. Survival analysis, including Kaplan-Meyer curves and multivariate competing risk analysis adjusting for sex, age, ASA-group, tumor stage, surgical radicality, and miss match repair status was performed. ResultsOf 1228 patients, 125 were available for analysis. 89 patients had received preoperative i.v. iron and 36 had not. The two groups were comparable on baseline and surgical characteristics. Median follow-up times were 4.74 in iron treated patients and 5 years in patients not receiving iron treatment. Five-year rate of non-recurrence was 85 % (0.74–0.91) in the i.v. iron treated group vs. 82 % (0.64–0.91) in the control group, non-significant difference. Multivariate survival analysis did not find iron treatment to be associated with recurrence rates (Hazard Ratio 0.88 (95 % ci; 0.31–2.51). ConclusionNo association between preoperative i.v. iron treatment and the five-year cancer recurrence rate in iron deficient anemic CRC patients was found.

Five-year changes in weight and risk of atrial fibrillation in the Danish Diet, Cancer, and Health Cohort.

Obesity is a major risk factor for atrial fibrillation (AF). Compared with stable weight, gaining weight was associated with a higher risk of incident AF in observational studies. The results, however, are conflicting regarding weight loss and risk of AF. This study aimed to assess the association between 5-year weight changes and risk of incident AF. The study was based on participants from the Danish Diet, Cancer, and Health Cohort. Body mass index (BMI) was assessed at a baseline examination and at a second examination 5 years later. Diagnoses of AF and co-morbidities were retrieved from the Danish National Patient Registry. In total, 43 758 participants without prior AF were included. The median age was 61 years and 54% were female. During a median follow-up of 15.7 years, 5312 individuals had incident AF (incidence rate 8.6/1000 person-years). Compared with stable weight, weight gain between 2.5 and 5 BMI units (kg/m2) was associated with a higher risk of AF [hazard ratio (HR) 1.24, 95% confidence interval (CI) 1.09-1.41]. Weight gain of 5 or more BMI units (kg/m2) was associated with a HR of 1.95 (95% CI 1.48-2.56) of incident AF. However, there was no statistically significant association between weight loss and risk of AF. Five-year weight gain was associated with greater risk of AF compared with stable weight in the Danish Diet, Cancer, and Health Cohort. There was no statistically significant association between weight loss and risk of AF.

Danish Prostate Registry (DanProst) – an Updated Version of the Danish Prostate Cancer Registry, Methodology, and Early Results

In 2016, we introduced the Danish Prostate Cancer Registry (DaPCaR) which was built on the National Pathology Register from 1995 to 2011. DaPCaR was laborious to use as most data had to be manually imputed with no regular updates. In here we present a new comprehensive centralized prostate registry called the Danish Prostate Registry (DanProst), which includes all men having undergone any histological evaluation of prostate tissue merged with laboratory-, treatment-, prescription data as well as vital status. Here the data included and the methodology of DanProst are described. DanProst is built upon all men with a histological assessment of the prostate from the Danish National Registry for Pathology. The primary histology and potential prostate cancer histological diagnosis for each unique individual is extracted and translated by newly made algorithms for topography, procedure, diagnostic conclusion, and pathological staging. Further information is added from DaPCaR, the CPR Registry, the Danish Cause of Death Registry, the Danish Cancer Registry, the National Patient Registry, the Danish Register of Laboratory Results for Research, and the Danish National Prescription Registry. The translation algorithms were validated based on the comparison with DaPCaR in the period 2010–2016. DanProst includes 190,422 men. A total of 95,152 (50%) men are diagnosed with prostate cancer until 2021. Median diagnostic PSA was 11 ng/ml, most men are diagnosed by ultrasound-guided biopsy (N = 63,751; 67%), and most frequently defined primary treatment was radical prostatectomy (N = 14,778; 19%). DanProst to DaPCaR coherency was > 99%, 95%, and 94% for the primary histological procedure, primary histological conclusion, and diagnostic histological conclusion, respectively. DanProst is a continuously updated, centrally kept, validated registry with automatic integration of data from other national registries, allowing for contemporary nationwide analysis in men with histological assessment of the prostate.

Alcohol Intake and Academic Performance and Dropout in High School: A Prospective Cohort Study in 65,233 Adolescents

PurposeDuring the teenage years, many adolescents start drinking alcohol, and binge drinking is prevalent. We investigated the relationship between alcohol intake and academic performance. MethodsWe conducted a longitudinal cohort study by combining data from the Danish National Youth Study on 65,233 high school students aged 15–20 years, with information on dropout and grade point average. We assessed associations between alcohol intake and academic performance using multilevel Poisson regression and linear regression, accounting for dependency between students from the same school and class. ResultsThe average alcohol intake was 10 drinks per week, and 43.6% engaged in binge drinking 3+ times per month. During follow-up, 9.8% of the boys and 6.7% of the girls dropped out. The incidence rate ratio was higher in never drinkers, frequent binge drinkers, and those with a high weekly alcohol intake as compared to those with a low intake. For example, the incidence rate ratio was 1.47 (95% confidence level: 1.24, 1.76) in girls who drank 21–27 drinks per week and 1.29 (95% confidence level: 1.13, 1.48) in girls who never drank as compared to those who drank <7 drinks per week. Alcohol associated with a lower grade point average over the entire span of intake in a dose-dependent manner, and similarly so in boys and girls. Findings were consistent in strata of socioeconomy and individual academic ambition. DiscussionAlcohol intake has implications for academic performance and poses a threat for the prospects of the individual as well as society. Policies and interventions aimed at lowering the intake among high school students are warranted.

Prognostic Factors for Relapse in Patients With Clinical Stage I Testicular Seminoma: A Nationwide, Population-Based Cohort Study.

Approximately 20% of patients with clinical stage I seminoma relapse. Tumor size and rete testis invasion have been identified as risk factors for relapse. However, the level of evidence supporting the use of these risk factors in clinical decision making is low. Previous studies have been hampered by selection bias and variable pathology reporting that limit interpretation and generalization of results. We assessed prognostic factors for relapse in an unselected nationwide population-based setting with centralized pathology review. Patients with clinical stage I seminoma diagnosed from January 2013 to December 2018 were identified in the prospective Danish Testicular Cancer database. By linkage to the Danish National Pathology Registry, histologic slides from the orchiectomy specimens were retrieved and reviewed blinded to the clinical outcome. Clinical data were obtained from medical records with follow-up until July 2022. The association between prespecified potential clinical and histopathologic prognostic factors and relapse was assessed by the use of Cox regression analysis. Of 924 patients included, 148 (16%) patients relapsed during a median follow-up of 6.3 years. Invasion of the testicular hilum (rete testis and hilar soft tissue), lymphovascular invasion, and elevated preorchiectomy levels of β-human chorionic gonadotropin and lactate dehydrogenase were independent predictors of relapse. The estimated 5-year risk of relapse ranged from 6% in patients with no risk factors to 62% in patients with all four risk factors with tumor extension into the hilar soft tissue of the testicular hilum. After internal model validation, the prognostic model had an overall concordance statistic of 0.70. The provided prognostic factors could replace current risk factors in guidelines and be used in future studies investigating risk-adapted follow-up and treatment strategies.

The bidirectional association between psychiatric disorders and sheltered homelessness.

Psychiatric disorders and homelessness are related, but temporal associations are unclear. We aimed to explore the overlap between hospital-based psychiatric disorders and sheltered homelessness. This population-based cohort study was conducted using the Danish registers e.g., the Danish Homeless Register and the Danish National Patient Register. The study cohort included all individuals aged 15 years or older, living in Denmark at least one day during 2002-2021 (born 1984-2006). First psychiatric diagnosis was used to define psychiatric disorder and first homeless shelter contact to define homelessness. Adjusted incidence rate ratios (IRRs) and cumulative incidences were estimated. Among 1 530 325 individuals accounting for 16 787 562 person-years at risk aged 15-38 years, 11 433 (0.8%) had at least one homeless shelter contact. Among 1 406 410 individuals accounting for 14 131 060 person-years at risk, 210 730 had at least one psychiatric disorder. People with any psychiatric disorder had increased risk of sheltered homelessness relative to individuals with no psychiatric disorder [IRR 9.2, 95% confidence interval (CI) 8.8-9.6]. Ten years after first psychiatric disorder, 3.0% (95% CI 2.9-3.1) had at least one homeless shelter contact. Individuals experiencing homelessness had increased risk of any psychiatric disorder compared to individuals with no homeless shelter contact (IRR 7.0, 95% CI 6.7-7.4). Ten years after first homeless shelter contact, 47.1% (45.3-48.0) had received a hospital-based psychiatric diagnosis. Strong bidirectional associations between psychiatric disorders and homelessness were identified. Health and social care professionals should be aware of and address these high risks of accumulated psychiatric and social problems.