Mental Health Conditions Among Children and Adolescents With Congenital Heart Disease: A Danish Population-Based Cohort Study.

BACKGROUND: Despite the known mental health burden among children with congenital heart disease (CHD), the literature is constrained by a lack of comparison cohorts and population-based follow-up data. We examined the incidence of mental health conditions among children with CHD, relative to 3 comparison cohorts. METHODS: This population-based cohort study identified all children with CHD (<18 years of age; n=16 473) in Denmark from 1996 to 2017, through linkage of individual-level data across national registries. This allowed for complete follow-up of the population. Comparison cohorts included children from the general population (n=162 204), siblings of children with CHD (n=20 079), and children with non-CHD major congenital anomalies (n=47 799). Mental health conditions were identified using inpatient and outpatient hospital discharge codes, prescription data, and data on use of community-based psychology, psychiatry, and psychotherapy services. We computed cumulative incidence by 18 years of age, incidence rates, and adjusted hazard ratios (aHRs) using Cox regression. aHRs accounted for sex, year of CHD diagnosis, parental mental health, and socioeconomic status. All estimates were stratified by age, sex, and CHD complexity. RESULTS: The cumulative incidence of mental health conditions by 18 years of age in the CHD cohort was 35.1% (95% CI, 34.0%-36.1%), corresponding to aHRs of 1.64 (95% CI, 1.58-1.71), 1.41 (95% CI, 1.30-1.52), and 1.02 (95% CI, 0.98-1.07) compared with the general population, sibling, and major congenital anomaly cohorts, respectively. Mental health incidence rates showed prominent peaks in early childhood and adolescence. Males and children with severe or single-ventricle CHD demonstrated higher incidence rates of mental health conditions relative to females and children with mild or moderate CHD, respectively. Compared with the general population and sibling cohorts, incidence rates and aHRs in the CHD cohort were highest for severe stress reactions, attention deficit/hyperactivity disorder, intellectual disability, and autism spectrum disorder. Compared with children in the major congenital anomaly cohort, the aHRs were close to 1. CONCLUSIONS: More than one-third of children with CHD were diagnosed or treated for a mental health condition by 18 years of age. Mental health conditions began early in life and were most prominent among males and children with severe or single-ventricle heart disease.

Low-Density Lipoprotein Cholesterol Is Predominantly Associated With Atherosclerotic Cardiovascular Disease Events in Patients With Evidence of Coronary Atherosclerosis: The Western Denmark Heart Registry.

BACKGROUND: Low-density lipoprotein cholesterol (LDL-C) is an important causal risk factor for atherosclerotic cardiovascular disease (ASCVD). However, a sizable proportion of middle-aged individuals with elevated LDL-C level have not developed coronary atherosclerosis as assessed by coronary artery calcification (CAC). Whether presence of CAC modifies the association of LDL-C with ASCVD risk is unknown. We evaluated the association of LDL-C with future ASCVD events in patients with and without CAC. METHODS: The study included 23 132 consecutive symptomatic patients evaluated for coronary artery disease using coronary computed tomography angiography (CTA) from the Western Denmark Heart Registry, a seminational, multicenter-based registry with longitudinal registration of patient and procedure data. We assessed the association of LDL-C level obtained before CTA with ASCVD (myocardial infarction and ischemic stroke) events occurring during follow-up stratified by CAC>0 versus CAC=0 using Cox regression models adjusted for baseline characteristics. Outcomes were identified through linkage among national registries covering all hospitals in Denmark. We replicated our results in the National Heart, Lung, and Blood Institute-funded Multi-Ethnic Study of Atherosclerosis. RESULTS: During a median follow-up of 4.3 years, 552 patients experienced a first ASCVD event. In the overall population, LDL-C (per 38.7 mg/dL increase) was associated with ASCVD events occurring during follow-up (adjusted hazard ratio [aHR], 1.14 [95% CI, 1.04-1.24]). When stratified by the presence or absence of baseline CAC, LDL-C was only associated with ASCVD in the 10 792/23 132 patients (47%) with CAC>0 (aHR, 1.18 [95% CI, 1.06-1.31]); no association was observed among the 12 340/23 132 patients (53%) with CAC=0 (aHR, 1.02 [95% CI, 0.87-1.18]). Similarly, a very high LDL-C level (>193 mg/dL) versus LDL-C <116 mg/dL was associated with ASCVD in patients with CAC>0 (aHR, 2.42 [95% CI, 1.59-3.67]) but not in those without CAC (aHR, 0.92 [0.48-1.79]). In patients with CAC=0, diabetes, current smoking, and low high-density lipoprotein cholesterol levels were associated with future ASCVD events. The principal findings were replicated in the Multi-Ethnic Study of Atherosclerosis. CONCLUSIONS: LDL-C appears to be almost exclusively associated with ASCVD events over ≈5 years of follow-up in middle-aged individuals with versus without evidence of coronary atherosclerosis. This information is valuable for individualized risk assessment among middle-aged people with or without coronary atherosclerosis.

Correction: Migraine and risk of premature myocardial infarction and stroke among men and women: A Danish population-based cohort study.

[This corrects the article DOI: 10.1371/journal.pmed.1004238.].

Validation of algorithms in studies based on routinely collected health data: general principles.

Clinicians, researchers, regulators, and other decision-makers increasingly rely on evidence from real-world data (RWD), including data routinely accumulating in health and administrative databases. RWD studies often rely on algorithms to operationalize variable definitions. An algorithm is a combination of codes or concepts used to identify persons with a specific health condition or characteristic. Establishing the validity of algorithms is a prerequisite for generating valid study findings that can ultimately inform evidence-based health care. This paper aims to systematize terminology, methods, and practical considerations relevant to the conduct of validation studies of RWD-based algorithms. We discuss measures of algorithm accuracy; gold/reference standard; study size; prioritizing accuracy measures; algorithm portability; and implication for interpretation. Information bias is common in epidemiologic studies, underscoring the importance of transparency in decisions regarding choice and prioritizing measures of algorithm validity. The validity of an algorithm should be judged in the context of a data source, and one size does not fit all. Prioritizing validity measures within a given data source depends on the role of a given variable in the analysis (eligibility criterion, exposure, outcome or covariate). Validation work should be part of routine maintenance of RWD sources.

Risk and adverse clinical outcomes of thrombocytopenia among patients with solid tumors-a Danish population-based cohort study.

BACKGROUND: Knowledge about thrombocytopenia among patients with solid tumors is scarce. We examined the risk of thrombocytopenia among patients with solid tumors and its association with adverse outcomes. METHODS: Using Danish health registries, we identified all patients with incident solid tumors from 2015-2018 (n = 52,380) and a platelet count measurement within 2 weeks prior to or on their cancer diagnosis date. The risk of thrombocytopenia was categorized as grades 0 (any platelet count × 109/L): <150; 1: <100; 2: <75; 3: <50; 4: <25, and 5: <10. To study the outcomes, each patient with thrombocytopenia was matched with up to five cancer patients without thrombocytopenia by age, sex, cancer type, and stage. Cox regression was used to compute hazard ratios (HRs) of bleeding, transfusion, or death, adjusting for confounding factors. RESULTS: The 1-year risk of thrombocytopenia was 23%, increasing to 30% at 4 years. This risk was higher in patients receiving chemotherapy (43% at 1 year and 49% at 4 years). Overall, patients with thrombocytopenia had higher 30-days rates of bleeding (HR = 1.72 [95% confidence interval, CI: 1.41-2.11]). Thrombocytopenia was also associated with an increased rate of transfusion, and death, but some of the risk estimates were imprecise. CONCLUSIONS: The risk of thrombocytopenia was substantial among patients with solid tumors and associated with adverse outcomes.

Randomized comparison of TAVI valves: The Compare-TAVI trial.

INTRODUCTION: Based on technical advancements and clinical evidence, transcatheter aortic valve implantation (TAVI) has been widely adopted. New generation TAVI valve platforms are continually being developed. Ideally, new valves should be superior or at least non-inferior regarding efficacy and safety, when compared to best-in-practice contemporary TAVI valves. METHODS AND ANALYSIS: The Compare-TAVI trial (ClinicalTrials.gov NCT04443023) was launched in 2020, to perform a 1:1 randomized comparison of new vs contemporary TAVI valves, preferably in all comers. Consecutive cohorts will be launched with sample sizes depending on the choice of interim analyses, expected event rates, and chosen superiority or non-inferiority margins. Enrollment has just been finalized in cohort B, comparing the Sapien 3/Sapien 3 Ultra Transcatheter Heart Valve (THV) series (Edwards Lifesciences, Irvine, California, USA) and the Myval/Myval Octacor THV series (Meril Life Sciences Pvt. Ltd., Vapi, Gujarat, India) balloon expandable valves. This non-inferiority study was aimed to include 1062 patients. The 1-year composite safety and efficacy endpoint comprises death, stroke, moderate-severe aortic regurgitation, and moderate-severe valve deterioration. Patients will be followed until withdrawal of consent, death, or completion of 10-year follow-up, whichever comes first. Secondary endpoints will be monitored at 30 days, 1, 3, 5, and 10 years. SUMMARY: The Compare-TAVI organization will launch consecutive cohorts wherein patients scheduled for TAVI are randomized to one of two valves. The aim is to ensure that the short- and long-term performance and safety of new valves being introduced is benchmarked against what achieved by best-in-practice contemporary valves.

Associations between pregnancy-related factors and birth characteristics with risk of rare uterine cancer subtypes: a Nordic population-based case-control study.

PURPOSE: Uterine sarcomas are a rare group of uterine malignancies. Due to the low incidence and changes in uterine sarcoma classification, risk factors are not well characterized. Our objective was to evaluate risk factors for uterine sarcoma and compare risk factors between uterine sarcoma, malignant mixed Mullerian tumors (MMMTs), and type I endometrial carcinomas. METHODS: This nested case-control study utilized linked data from population-based medical birth and cancer registries in Denmark, Finland, Norway, and Sweden. Up to 10 controls were matched on country and birth year for each uterine cancer case. Using multivariable adjusted multinomial logistic regression, estimates of the associations between pregnancy-related factors and risk of uterine sarcoma, MMMTs, and type I endometrial carcinomas were determined. RESULTS: Having a very-low-birth-weight infant (< 1500 vs. 2500-3999 g: OR [95% CI] 2.83 [1.61-4.96]) was associated with an increased risk of uterine sarcoma. Whereas, having a more recent pregnancy was associated with reduced risks of MMMT (< 10 vs. ≥ 30 years: 0.66 [0.20-2.23]) and type 1 endometrial carcinomas (0.35 [0.30-0.41]) but not uterine sarcomas (1.33 [0.90-1.98], p-heterogeneity < 0.01). CONCLUSION: Our study provides evidence that risk factors for uterine sarcoma and MMMT, previously grouped with uterine sarcomas, vary substantially. Additionally, MMMT and type I endometrial carcinomas are more similar than uterine sarcoma in that pregnancy complications like gestational hypertension and preeclampsia were associated with reduced risks of both but not uterine sarcoma, suggesting different etiologies.

Use of Latent Class Analysis to Predict Intensive Care Unit Admission and Mortality in Children with a Major Congenital Anomaly.

OBJECTIVE: To define major congenital anomaly (CA) subgroups and assess outcome variability based on defined subgroups. STUDY DESIGN: This population-based cohort study used registries in Denmark for children born with a major CA between January 1997 and December 2016, with follow-up until December 2018. We performed a latent class analysis (LCA) using child and family clinical and sociodemographic characteristics present at birth, incorporating additional variables occurring until age of 24 months. Cox proportional hazards regression models estimated hazard ratios (HRs) of pediatric mortality and intensive care unit (ICU) admissions for identified LCA classes. RESULTS: The study included 27 192 children born with a major CA. Twelve variables led to a 4-class solution (entropy = 0.74): (1) children born with higher income and fewer comorbidities (55.4%), (2) children born to young mothers with lower income (24.8%), (3) children born prematurely (10.0%), and (4) children with multiorgan involvement and developmental disability (9.8%). Compared with those in Class 1, mortality and ICU admissions were highest in Class 4 (HR = 8.9, 95% CI = 6.4-12.6 and HR = 4.1, 95% CI = 3.6-4.7, respectively). More modest increases were observed among the other classes for mortality and ICU admissions (Class 2: HR = 1.7, 95% CI = 1.1-2.5 and HR = 1.3, 95% CI = 1.1-1.4, respectively; Class 3: HR = 2.5, 95% CI = 1.5-4.2 and HR = 1.5, 95% CI = 1.3-1.9, respectively). CONCLUSIONS: Children with a major CA can be categorized into meaningful subgroups with good discriminative ability. These groupings may be useful for risk-stratification in outcome studies.

Outcome of pregnancy oral glucose tolerance test and preterm birth.

BACKGROUND: Gestational diabetes is associated with adverse outcomes such as preterm birth (<37 weeks). However, there is no international consensus on screening criteria or diagnostic levels for gestational diabetes, and it is unknown whether body mass index (BMI) or obesity modifies the relation between glucose level and preterm birth. METHODS: We studied a pregnancy cohort restricted to two Danish regions from the linked Danish Medical Birth Register to study associations between glucose measurements from the 2-hour post-load 75-gram oral glucose tolerance test (one-step approach) and preterm birth from 2004-2018. In Denmark, gestational diabetes screening is a targeted strategy for mothers with identified risk factors. We used Poisson regression to estimate rate ratios (RR) of preterm birth with z-standardized glucose measurements. We assessed effect measure modification by stratifying analyses and testing for heterogeneity. RESULTS: Among 11,337 pregnancies (6.2% delivered preterm), we observed an adjusted preterm birth RR of 1.2 (95% CI: 1.1-1.3) for a 1 standard deviation glucose increase of 1.4 mmol/L from the mean 6.7 mmol/L. There was evidence for effect measure modification by obesity, e.g., adjusted RR for non-obese (BMI <30): 1.2 (95%CI: 1.1-1.3) vs. obese (BMI ≥30): 1.3 (95%CI: 1.2-1.5), P=0.05 for heterogeneity. CONCLUSIONS: Among mothers screened for gestational diabetes, increased glucose levels, even those below the diagnostic level for gestational diabetes in Denmark, were associated with increased preterm birth risk. Obesity (BMI ≥30) may be an effect measure modifier, not just a confounder, of the relation between blood glucose and preterm birth risk.

Urticaria and the risk of cancer: a Danish population-based cohort study.

BACKGROUND: Urticaria has been tentatively linked to cancer, but epidemiological evidence supporting this link is sparse and conflicting. We therefore conducted a population-based cohort study using healthcare databases of the Danish population (January 1980-December 2022). We followed 87,507 people for a median of 10.1 years after first hospital contact for urticaria. OBJECTIVES: To examine associations of a hospital diagnosis of urticaria with incident cancer. METHODS: We computed absolute risk of cancer and standardized incidence ratios (SIRs) with 95% confidence intervals (CIs) standardized to Danish national cancer rates. In a cross-sectional analysis, we examined whether the extent of cancer spread differed between people with vs. without a previous urticaria diagnosis. RESULTS: The overall SIR for all types of cancer was 1.09 (95% CI, 1.06-1.11) based on 7,788 observed vs. 7,161 expected cases. The risk for any cancer was 0.7% (95% CI, 0.6-0.7) for the first year of follow-up. Cancer was diagnosed in 588 people with urticaria during the first year of follow-up (SIR 1.49, 95% CI, 1.38-1.62) and in 7,200 people thereafter (SIR 1.06, 95% CI, 1.04-1.09). During the first year of follow-up, we found strong associations with hematological cancers (e.g., non-Hodgkin lymphoma SIR 2.91, 95% CI, 1.92-4.23). Cancer stage was similar in people with vs. without previous urticaria diagnosis. CONCLUSIONS: At the time of urticaria diagnosis, or in the first year afterwards, we found a large increase in the risk for cancer. In subsequent years, a persistent 6% increase in risk remained. Diagnostic efforts may partly explain the elevated short-term risk, but occult cancer may promote urticaria, or cancer and urticaria share common risk factors.

Lifetime and 10-year cardiovascular risk prediction in individuals with type 1 diabetes: The LIFE-T1D model.

AIMS: To develop and externally validate the LIFE-T1D model for the estimation of lifetime and 10-year risk of cardiovascular disease (CVD) in individuals with type 1 diabetes. MATERIALS AND METHODS: A sex-specific competing risk-adjusted Cox proportional hazards model was derived in individuals with type 1 diabetes without prior CVD from the Swedish National Diabetes Register (NDR), using age as the time axis. Predictors included age at diabetes onset, smoking status, body mass index, systolic blood pressure, glycated haemoglobin level, estimated glomerular filtration rate, non-high-density lipoprotein cholesterol, albuminuria and retinopathy. The model was externally validated in the Danish Funen Diabetes Database (FDDB) and the UK Biobank. RESULTS: During a median follow-up of 11.8 years (interquartile interval 6.1-17.1 years), 4608 CVD events and 1316 non-CVD deaths were observed in the NDR (n = 39 756). The internal validation c-statistic was 0.85 (95% confidence interval [CI] 0.84-0.85) and the external validation c-statistics were 0.77 (95% CI 0.74-0.81) for the FDDB (n = 2709) and 0.73 (95% CI 0.70-0.77) for the UK Biobank (n = 1022). Predicted risks were consistent with the observed incidence in the derivation and both validation cohorts. CONCLUSIONS: The LIFE-T1D model can estimate lifetime risk of CVD and CVD-free life expectancy in individuals with type 1 diabetes without previous CVD. This model can facilitate individualized CVD prevention among individuals with type 1 diabetes. Validation in additional cohorts will improve future clinical implementation.

Association between pregnancy affected by vaginal bleeding and women's mortality: A cohort study.

OBJECTIVE: To investigate the association between vaginal bleeding (VB) in pregnancy and women's mortality, using VB-unaffected pregnancies, terminations and miscarriages as comparators. DESIGN: Observational cohort study. SETTING: Nationwide registries of Denmark linked at an individual level. POPULATION OR SAMPLE: 1 354 181 women and their 3 162 317 pregnancies (1979-2017), including 70 835 VB-affected pregnancies and comparators: 2 236 359 VB-unaffected pregnancies ending in childbirth; 589 697 terminations; and 265 426 miscarriages. METHODS: We followed pregnancies until the earliest date of woman's death, emigration or end of data. MAIN OUTCOME MEASURES: All-cause and cause-specific mortality rates per 10 000 person-years (PY) and hazard ratios (HRs) with 95% confidence intervals (CIs) adjusted using Cox proportional hazards regression for age, calendar year, pre-existing chronic conditions and socio-economic factors. RESULTS: There were 2320 deaths from any cause among women following VB-affected pregnancy (mortality rate 15.2, 95% CI 14.6-15.9 per 10 000 PY); 55 030 deaths following VB-unaffected pregnancy (mortality rate 12.7, 95% CI 12.6-12.8); 27 500 deaths following a termination (mortality rate 21.9, 95% CI 21.6-22.1), and 10 865 deaths following a miscarriage (mortality rate 19.2, 95% CI 18.8-19.6). For comparison of VB-affected versus VB-unaffected pregnancies, associations with all-cause (HR 1.14, 95% CI 1.09-1.19), natural causes (HR 1.15, 95% CI 1.09-1.22) and non-natural causes (HR 1.27, 95% CI 1.08-1.48) mortality were attenuated in a sensitivity analysis of pregnancies recorded in 1994-2017 (HR 1.00, 95% CI 0.90-1.12, HR 0.98, 95% CI 0.85-1.14 and HR 1.04, 95% CI 0.72-1.51, respectively). Contrasts with remaining comparators did not suggest increased risks of all-cause, natural or non-natural mortality causes. CONCLUSION: We found no evidence of an increased risk of women's mortality following VB-affected versus VB-unaffected pregnancy, termination or miscarriage.

Association between maternal employment status and presence of children with major congenital anomalies in Denmark.

IMPORTANCE: The burden of caring for children with complex medical problems such as major congenital anomalies falls principally on mothers, who in turn suffer a variety of potentially severe economic consequences. As well, health consequences of caregiving often further impact the social and economic prospects of mothers of children with major congenital anomalies (MCMCAs). Evaluating the long-term economic consequences of extensive in-home caregiving among MCMCAs can inform strategies to mitigate these effects. OBJECTIVE: To assess whether MCMCAs face reduced employment and increased need for disability benefits over a 20-year period. DESIGN: A population-based matched cohort study. SETTING: Denmark. PARTICIPANTS: All women who gave birth to a singleton child with a major congenital anomaly in Denmark between January 1, 1997 and December 31, 2017 (n = 23,637) and a comparison cohort of mothers matched by maternal age, parity, and infant's year of birth (n = 234,586). EXPOSURES: Liveborn infant with a major congenital anomaly. MAIN OUTCOMES AND MEASURES: The primary outcome was mothers' employment status, stratified by their child's age. Employment status was categorized as employed, outside the workforce (on temporary leave, holding a flexible job, or pursuing education), or unemployed; the number of weeks in each category was measured over time. The secondary outcome was time to receipt of a disability pension, which in Denmark implies permanent exit from the labor market. We used a negative binomial regression model to estimate the number of weeks in each employment category, stratified by the child's age (i.e., 0-1 year, > 1-6 years, 7-13 years, 14-18 years). A Cox proportional hazards regression model was used to compute hazard ratios as a measure of the relative risk of receiving a disability pension. Rate ratios and hazard ratios were adjusted for maternal demographics, pregnancy history, health, and infant's year of birth. RESULTS: During 1-6 years after delivery, MCMCAs were outside the workforce for a median of 50 weeks (IQR, 6-107 weeks), while members of the comparison cohort were outside the workforce for a median of 48 weeks (IQR, 4-98 weeks), corresponding to an adjusted rate ratio [ARR] of 1.05 (95% confidence interval [CI], 1.04-1.07). During the first year after delivery, MCMCAs were more likely to be employed than mothers in the comparison cohort (ARR, 1.08; 95% CI, 1.06-1.10). At all timepoints thereafter, MCMCAs had a lower rate of workforce participation. The rate of being outside the workforce was 5% higher than mothers in the comparison cohort during 1-6 years after delivery (ARR, 1.05; 95% CI, 1.04-1.07), 9% higher during 7-13 years after delivery (ARR, 1.09; 95% CI, 1.06-1.12), and 12% higher during 14-18 years after delivery (ARR, 1.12; 95% CI, 1.07-1.18). Overall, MCMCAs had a 20% increased risk of receiving a disability pension during follow-up than mothers in the matched comparison cohort [incidence rates 3.10 per 1000 person-years (95% CI, 2.89-3.32) vs. 2.34 per 1000 person-years (95% CI, 2.29-2.40), adjusted hazard ratio, 1.20; 95% CI, 1.11-1.29]. CONCLUSION AND RELEVANCE: MCMCAs were less likely to participate in the Danish workforce, less likely to be employed, and more likely to receive disability pensions than mothers of unaffected children. The rate of leaving the workforce intensified as their affected children grew older. The high demands of caregiving among MCMCAs may have long-term employment consequences even in nations with comprehensive and heavily tax-supported childcare systems, such as Denmark.

Enhancing the data capture of periprosthetic joint infections in the Danish Knee Arthroplasty Registry: validity assessment and incidence estimation.

BACKGROUND AND PURPOSE: Revisions due to periprosthetic joint infection (PJI) are underestimated in national arthroplasty registries. Our primary objective was to assess the validity in the Danish Knee Arthroplasty Register (DKR) of revisions performed due to PJI against the Healthcare-Associated Infections Database (HAIBA). The secondary aim was to describe the cumulative incidences of revision due to PJI within 1 year of primary total knee arthroplasty (TKA) according to the DKR, HAIBA, and DKR/HAIBA combined. METHODS: This longitudinal observational cohort study included 56,305 primary TKAs (2010-2018), reported in both the DKR and HAIBA. In the DKR, revision performed due to PJI was based on pre- and intraoperative assessment disclosed by the surgeon immediately after surgery. In HAIBA, PJI was identified from knee-related revision procedures coinciding with 2 biopsies with identical microbiological pathogens. We calculated the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of revision due to PJI in the DKR (vs. HAIBA, within 1 year of TKA) with 95% confidence intervals (CI). Cumulative incidences were calculated using the Kaplan-Meier method. RESULTS: The DKR's sensitivity for PJI revision was 58% (CI 53-62) and varied by TKA year (41%-68%) and prosthetic type (31% for monoblock; 63% for modular). The specificity was 99.8% (CI 99.7-99.8), PPV 64% (CI 62-72), and NPV 99.6% (CI 99.6-99.7). 80% of PJI cases not captured by the DKR were caused by non-reporting rather than misclassification. 33% of PJI cases in the DKR or HAIBA were culture-negative. Considering potential misclassifications, the best-case sensitivity was 64%. The cumulative incidences of PJI were 0.8% in the DKR, 0.9% in HAIBA, and 1.1% when combining data. CONCLUSION: The sensitivity of revision due to PJI in the DKR was 58%. The cumulative incidence of PJI within 1 year after TKA was highest (1.1%) when combining the DKR and HAIBA, showing that incorporating microbiology data into arthroplasty registries can enhance PJI validity.

Risk and Prognosis of Cancer in Patients With Cerebral Venous Thrombosis Compared With the Danish General Population.

BACKGROUND: Whether cerebral venous thrombosis (CVT) is a marker of cancer in clinical practice remains unknown. Little is known about the prognosis of cancer detected subsequent to CVT. METHODS: We used Danish nationwide registries (1996-2019) to identify patients with a first-time primary inpatient diagnosis of CVT without a history of cancer (N=811, 65% women, median age 42 years). We assessed the risk of an incident cancer diagnosis using standardized incidence ratios (SIRs). This measure contrasts the number of observed cancers among patients with CVT to the number of expected cancers where patients with CVT have the same cancer risk as the general population. We used Kaplan-Meier survival analysis and Cox regression to compare the survival of patients with both cancer and CVT with the survival of patients with cancer but without CVT, matched on cancer site, sex, age, and year of cancer diagnosis. RESULTS: Observing 43 incident cancer cases during follow-up, the overall SIR was unity (SIR, 1.04 [95% CI, 0.75-1.40]). However, the risk was ≈7-fold the expected level in the first 3 months following CVT diagnosis (SIR, 7.00 [95% CI, 3.02-13.80]) and ≈2-fold the expected level from 3 to 12 months following CVT diagnosis (SIR, 2.21 [95% CI, 0.89-4.56]). By 12 months following CVT diagnosis, the risk resembled the expected level (SIR, 0.76 [95% CI, 0.50-1.09]). Survival among cancer patients with prior CVT versus cancer patients without prior CVT was 91% versus 87% after 6 months and 65% versus 70% after 5 years. The adjusted hazard ratio of death was 0.78 (95% CI, 0.44-1.38). CONCLUSIONS: Patients with CVT were not at overall increased risk of a cancer diagnosis, except in the first 3 months after diagnosis during which period the risk was elevated ≈7-fold. The estimate from this early period, however, was based on only a few cancer diagnoses. Unlike other forms of venous thrombosis, a prior diagnosis of CVT did not negatively impact cancer survival.

Migraine and risk of premature myocardial infarction and stroke among men and women: A Danish population-based cohort study.

BACKGROUND: Migraine carries risk of myocardial infarction (MI) and stroke. The risk of premature MI (i.e., among young adults) and stroke differs between men and women; previous studies indicate that migraine is mainly associated with an increased risk of stroke among young women. The aim of this study was to examine impact of migraine on the risk of premature (age ≤60 years) MI and ischemic/hemorrhagic stroke among men and women. METHODS AND FINDINGS: Using Danish medical registries, we conducted a nationwide population-based cohort study (1996 to 2018). Redeemed prescriptions for migraine-specific medication were used to identify women with migraine (n = 179,680) and men with migraine (n = 40,757). These individuals were matched on sex, index year, and birth year 1:5 with a random sample of the general population who did not use migraine-specific medication. All individuals were required to be between 18 and 60 years old. Median age was 41.5 years for women and 40.3 years for men. The main outcome measures to assess impact of migraine were absolute risk differences (RDs) and hazard ratios (HRs) with 95% confidence intervals (CIs) of premature MI, ischemic, and hemorrhagic stroke, comparing individuals with migraine to migraine-free individuals of the same sex. HRs were adjusted for age, index year, and comorbidities. The RD of premature MI for those with migraine versus no migraine was 0.3% (95% CI [0.2%, 0.4%]; p < 0.001) for women and 0.3% (95% CI [-0.1%, 0.6%]; p = 0.061) for men. The adjusted HR was 1.22 (95% CI [1.14, 1.31]; p < 0.001) for women and 1.07 (95% CI [0.97, 1.17]; p = 0.164) for men. The RD of premature ischemic stroke for migraine versus no migraine was 0.3% (95% CI [0.2%, 0.4%]; p < 0.001) for women and 0.5% (95% CI [0.1%, 0.8%]; p < 0.001) for men. The adjusted HR was 1.21 (95% CI [1.13, 1.30]; p < 0.001) for women and 1.23 (95% CI [1.10, 1.38]; p < 0.001) for men. The RD of premature hemorrhagic stroke for migraine versus no migraine was 0.1% (95% CI [0.0%, 0.2%]; p = 0.011) for women and -0.1% (95% CI [-0.3%, 0.0%]; p = 0.176) for men. The adjusted HR was 1.13 (95% CI [1.02, 1.24]; p = 0.014) for women and 0.85 (95% CI [0.69, 1.05]; p = 0.131) for men. The main limitation of this study was the risk of misclassification of migraine, which could lead to underestimation of the impact of migraine on each outcome. CONCLUSIONS: In this study, we observed that migraine was associated with similarly increased risk of premature ischemic stroke among men and women. For premature MI and hemorrhagic stroke, there may be an increased risk associated with migraine only among women.

Overweight or obesity in children born after assisted reproductive technologies in Denmark: A population-based cohort study.

BACKGROUND: The association between assisted reproductive technologies (ARTs) and the body mass index (BMI) of children remains controversial. Confounding by morbidity and other factors associated with parental infertility may have biased studies comparing children born after ART with children born after no treatment. We investigated the associations between different fertility treatments and BMI in children at age 5 to 8 years, adjusting for and stratifying by causes of parental infertility. METHODS AND FINDINGS: This Danish cohort study included 327,301 children born between 2007 and 2012 (51% males, median age at follow-up 7 years). Of these, 13,675 were born after ART, 7,728 were born after ovulation induction with or without intrauterine insemination [OI/IUI], and 305,898 were born after no fertility treatments. Using the International Obesity Task Force (IOTF) standards, we defined overweight (BMI ≥ IOTF-25) and obesity (BMI ≥ IOTF-30). We compared children born after ART versus OI/IUI; intracytoplasmic sperm injection (ICSI) versus conventional in vitro fertilization (IVF); and frozen-thawed versus fresh embryo transfer and estimated crude and adjusted prevalences of children with overweight or obesity at age 5 to 8 years, prevalence odds ratios (PORs), and differences in mean BMI z-scores. Adjustment was performed using stabilized inverse probability of treatment weights, including parity, year of conception, parental causes of infertility, age, educational level, comorbidities, maternal country of origin, BMI, and smoking as covariates. The crude prevalence of obesity was 1.9% in children born after ART, 2.0% in those born after OI/IUI, and 2.7% in those born after no fertility treatment. After adjustment, children born after ART and OI/IUI had the same prevalence of being overweight (11%; POR 1.00, 95% confidence interval [CI] 0.91 to 1.11; p = 0.95) or obese (1.9%; POR 1.01, 95% CI 0.79 to 1.29; p = 0.94). Comparison of ICSI with conventional IVF yielded similar pattern (POR 0.95, 95% CI 0.83 to 1.07; p = 0.39 for overweight and POR 1.16, 95% CI 0.84 to 1.61; p = 0.36 for obesity). Obesity was more prevalent after frozen-thawed (2.7%) than fresh embryo transfer (1.8%) (POR 1.54, 95% CI 1.09 to 2.17; p = 0.01). The associations between fertility treatments and BMI were only modestly different in subgroups defined by the cause of infertility. Study limitations include potential residual confounding, restriction to live births, and lack of detailed technical information about the IVF procedures. CONCLUSIONS: We found no association with BMI at age 5 to 8 years when comparing ART versus OI/IUI or when comparing ICSI versus conventional IVF. However, use of frozen-thawed embryo transfer was associated with a 1.5-fold increased risk of obesity compared to fresh embryo transfer. Despite an elevated relative risk, the absolute risk difference was low.

Birth Weight, Gestational Age, and Risk of Cardiovascular Disease in Early Adulthood: Influence of Familial Factors.

The association between intrauterine growth restriction and cardiovascular disease (CVD) later in life might be confounded by familial factors. We conducted a binational register-based cohort study to assess associations of birth weight for gestational age (GA), a proxy for intrauterine growth restriction, and GA with CVD risk in early adulthood, before and after addressing familial factors via sibling comparison. We included 3,410,334 live nonmalformed singleton births from Sweden (1973-1996) and Denmark (1978-1998). During a median follow-up period of 10 years from age 18 years onwards, 29,742 individuals developed incident CVD (hypertension, ischemic heart disease, or cerebrovascular disease). Compared with individuals born with appropriate birth weight for GA (AGA; 10th-90th percentiles) or full term (39-40 gestational weeks), individuals born severely small for GA (SGA; ≤3rd percentile) or preterm (22-36 weeks) were at increased risk of CVD (hazard ratio (HR) = 1.38 (95% confidence interval (CI): 1.32, 1.45) and HR = 1.31 (95% CI: 1.25, 1.38), respectively). The association was attenuated when comparing individuals born SGA with their AGA siblings (HR = 1.11, 95% CI: 0.99, 1.25) but remained robust when comparing individuals born preterm with their term siblings (HR = 1.21, 95% CI: 1.07, 1.37). Our findings suggest that both SGA and preterm birth are associated with CVD risk in early adulthood, with greater familial confounding noted for SGA birth.

Effect of a FIT-Based Colorectal Cancer Screening Program on Mortality Estimated by the Regression Discontinuity Design.

The fecal immunochemical test (FIT) has been implemented in colorectal cancer (CRC) screening programs, but effect evaluations are lacking. We evaluated the effect of a positive FIT on all-cause and CRC mortality using the regression discontinuity design. The Danish CRC screening program invites all residents 50-74 years old, using a 20-µg hemoglobin/g feces cutoff for colonoscopy referral. In this cohort study, we followed all first-time screening participants from 2014-2019 until 2020. We estimated the local effect of screening results, of just above the cutoff vs. just below, as hazard ratios (HRs) between models fitted at each side of the cutoff. We conducted the analysis within a narrow hemoglobin range (≥17 and <23, n = 16,428) and a wider range (≥14 and <26, n = 35,353). Those screened just above the cutoff had lower all-cause mortality compared with below (HR = 0.87, 95% confidence interval: 0.69; 1.10), estimated from the narrow range. The CRC mortality analysis had few outcomes. In the wider range, those with a FIT just above the cutoff had a lower hazard of CRC mortality compared with just below the cutoff (HR = 0.49, 95% confidence interval: 0.17; 1.41). A FIT result just above the cutoff, leading to referral to colonoscopy, pointed towards reduced all-cause and CRC mortality compared with just below the cutoff.

Burden of Chronic Obstructive Pulmonary Disease Attributable to Tuberculosis: A Microsimulation Study.

Tuberculosis (TB) is a risk factor for chronic obstructive pulmonary disease (COPD), but COPD is also a predictor of TB. The excess life-years lost to COPD caused by TB can potentially be saved by screening for and treating TB infection. We examined the number of life-years that could be saved by preventing TB and TB-attributable COPD. We compared the observed (no intervention) and counterfactual microsimulation models constructed from observed rates in the Danish National Patient Registry (covering all Danish hospitals between 1995 and 2014). In the Danish population of TB and COPD-naive individuals (n = 5,206,922), 27,783 persons (0.5%) developed TB. Among those who developed TB, 14,438 (52.0%) developed TB with COPD. Preventing TB saved 186,469 life-years overall. The excess number of life-years lost to TB alone was 7.07 years per person, and the additional number of life-years lost among persons who developed COPD after TB was 4.86 years per person. The life-years lost to TB-associated COPD are substantial, even in regions where TB can be expected to be identified and treated promptly. Prevention of TB could prevent a substantial amount of COPD-related morbidity; the benefit of screening and treatment for TB infection is underestimated by considering morbidity from TB alone.