Nationwide Register-based Cohort Study Research Articles

Imprinting disorders in children conceived with assisted reproductive technology in Sweden

ObjectiveTo assess whether the use of assisted reproductive technology for conception is associated with imprinting disorders in children and the impact of parental factors related to infertility. DesignA nationwide register-based cohort study. SubjectsAll liveborn singletons in Sweden (N = 2 084 127) between 1997-2017 with follow-up to December 31, 2018. ExposureThe use of specific methods implemented in the assisted reproductive technology Main Outcome MeasuresThe International Classification of Diseases version 10 was used to identify three distinct imprinting disorder groups: Prader-Willi/Silver-Russell syndrome, Beckwith-Wiedemann syndrome, and central precocious puberty. The Cox model combined with inverse probability treatment weights were used to estimate weighted hazard ratio (wHR) with 95% confidence interval (CI), accounting for multiple confounders. ResultsA total of 1044 children were diagnosed with the disorders of interest, and 52 of them were conceived with assisted reproductive technology. The overall risk of being diagnosed with any of the studied imprinting disorders was elevated in children conceived with ART compared to all other children (HR 1.84, 95% CI: 1.38-2.45). After adjusting for parental background factors, the association was partially attenuated (wHR 1.50, 95% CI: 0.97-2.32), but remained also in the weighted comparison restricted to children of couples with known infertility (wHR 1.52, 95% CI: 1.05-2.21). For the specific diagnoses of Prader-Willi/Silver-Russell syndrome and Beckwith-Wiedemann syndrome, compared to children of couples with known infertility, children conceived with assisted reproductive technology showed a small excess risk, which could not be distinguished from the null (wHR 1.56 [95% CI: 0.93-2.62] and 1.80 [95% CI: 0.99-3.28], respectively). Further subgroup analysis showed that the combined use of intra-cytoplasmic sperm injection and cryopreserved embryos was associated with higher risk of both Prader-Willi/Silver-Russell syndrome (wHR 4.60, 95% CI: 1.72-12.28) and Beckwith-Wiedemann syndrome (wHR 6.69, 95% CI: 2.09-21.45). The number of central precocious puberty cases in children conceived with assisted reproductive technology was too small (N=3) to make any meaningful inference. ConclusionThe combined use of intra-cytoplasmic sperm injection and cryopreserved embryos was associated with small elevated risks of Prader-Willi/Silver-Russell syndrome and Beckwith-Wiedemann syndrome in children, independent of parental factors related to infertlity.

Impact of childhood traumatic brain injury on fitness for service class, length of service period, and cognitive performance during military service in Finland from 1998 to 2018: A retrospective register-based nationwide cohort study.

Traumatic brain injury (TBI) can cause neuronal damage and cerebrovascular dysfunction, leading to acute brain dysfunction and considerable physical and mental impairment long after initial injury. Our goal was to assess the impact of pediatric TBI (pTBI) on military service, completed by 65-70% of men in Finland. We conducted a retrospective register-based nationwide cohort study. All patients aged 0 to 17 years at the time of TBI, between 1998 and 2018, were included. Operatively and conservatively treated patients with pTBI were analyzed separately. The reference group was comprised of individuals with upper and lower extremity fractures. Information on length of service time, service completion, fitness for service class, and cognitive performance in a basic cognitive test (b-test) was gathered from the Finnish Military Records for both groups. Linear and logistic regression with 95% CI were used in comparisons. Our study group comprised 12 281 patients with pTBI and 20 338 reference group patients who participated in conscription. A total of 8 507 (66.5%) men in the pTBI group and 14 953 (71.2%) men in the reference group completed military service during the follow-up period. Men in the reference group were more likely to complete military service (OR 1.26, CI 1.18-1.34). A total of 31 (23.3%) men with operatively treated pTBI completed the military service. Men with conservatively treated pTBI had a much higher service rate (OR 7.20, CI 4.73-11.1). In the pTBI group, men (OR 1.26, CI 1.18-1.34) and women (OR 2.05, CI 1.27-3.36) were more likely to interrupt military service than the reference group. The PTBI group scored 0.15 points (CI 0.10-0.20) less than the reference group in cognitive b-test. PTBI groups had slightly shorter military service periods and higher interruption rate than our reference-group. There were only minor differences between groups in cognitive b-test.

Thyroid dysfunction and exudative age-related macular degeneration - A longitudinal nationwide registry-based cohort study.

The association between thyroid dysfunction and exudative age-related macular degeneration (AMD) is unknown. In this Danish longitudinal nationwide registry-based cohort study we included all Danish residents aged 50-100 between 2008 and 2018. Using the Danish national registries, we studied the association between thyroid dysfunction and exudative AMD. Thyroid dysfunction was classified as two consecutive redeemed prescriptions of thyroid hormones (hypothyroidism) or anti-thyroid medication (hyperthyroidism). Exudative AMD was classified as an ICD diagnosis of AMD and a code for anti-VEGF treatment. All patients are treated for exudative AMD in a hospital in Denmark, and we therefore have complete registration of this patient group. We included 2 087 305 individuals, of which 1 072 567 (51.4%) were women; 59 318 (2.8%) had hypothyroidism, and 33 922 (1.6%) had hyperthyroidism. During a median follow-up of 11 years, 26 998 (1.3%) people developed exudative AMD. Hypothyroidism (adjusted hazard ratio [HR]: 1.17; 95% confidence interval [CI] 1.10-1.25; p < 0.001) and hyperthyroidism (HR: 1.23; 95% CI:1.13-1.34; p < 0.001) were both associated with the development of exudative AMD. The age-stratified analyses yielded similar results to the main analyses, except that the risks were exaggerated in the older part of the population. This is the first longitudinal nationwide study showing that both hypo- and hyperthyroidism are associated with an increased risk of exudative AMD. AMD is a quantitative problem in the population and our findings could have a public health impact. Further studies are needed to study the underlying mechanisms of the association.

Gender affirming treatment and employment rate in 3,812 Danish transgender persons and 38,120 controls. A nationwide register-based cohort study

Gender affirming treatment and employment rate in 3,812 Danish transgender persons and 38,120 controls. A nationwide register-based cohort study

Pregnancy loss in women with endocrine disorders - a nationwide registry-based cohort study of 366,548 Danish women

Pregnancy loss in women with endocrine disorders - a nationwide registry-based cohort study of 366,548 Danish women

Per- and polyfluoroalkyl substances (PFAS) and fetal growth: A nation-wide register-based study on PFAS in drinking water

BackgroundThere is inconclusive evidence for an association between per- and polyfluoroalkyl substances (PFAS) and fetal growth. ObjectivesWe conducted a nation-wide register-based cohort study to assess the associations of the estimated maternal exposure to the sum (PFAS4) of perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA) and perfluorohexane sulfonic acid (PFHxS) with birthweight as well as risk of small- (SGA) and large-for-gestational-age (LGA). Materials and methodsWe included all births in Sweden during 2012–2018 of mothers residing ≥ four years prior to partus in localities served by municipal drinking water where PFAS were measured in raw and drinking water. Using a one-compartment toxicokinetic model we estimated cumulative maternal blood levels of PFAS4 during pregnancy by linking residential history, municipal PFAS water concentration and year-specific background serum PFAS concentrations in Sweden. Individual birth outcomes and covariates were obtained via register linkage. Mean values and 95 % confidence intervals (CI) of β coefficients and odds ratios (OR) were estimated by linear and logistic regressions, respectively. Quantile g-computation regression was conducted to assess the impact of PFAS4 mixture. ResultsAmong the 248,804 singleton newborns included, no overall association was observed for PFAS4 and birthweight or SGA. However, an association was seen for LGA, multivariable-adjusted OR 1.08 (95% CI: 1.01–1.16) when comparing the highest PFAS4 quartile to the lowest. These associations remained for mixture effect approach where all PFAS, except for PFOA, contributed with a positive weight. DiscussionsWe observed an association of the sum of PFAS4 – especially PFOS – with increased risk of LGA, but not with SGA or birthweight. The limitations linked to the exposure assessment still require caution in the interpretation.

Diverticulitis Is Associated with Increased Risk of Colon Cancer-A Nationwide Register-Based Cohort Study.

Background: An association between diverticulitis and colon cancer has been proposed. The evidence is conflicting, and the guidelines differ regarding recommended follow-up with colonoscopy after an episode of diverticulitis. To guide regimes for follow-up, this study aimed to investigate if patients with diverticulitis have an increased risk of colon cancer. Methods: This study is reported according to the RECORD statement. We performed a cohort study with linked data from nationwide Danish registers. The inclusion period was 1997-2009, and the complete study period was 1995-2013. The primary outcome was the risk of developing colon cancer estimated using a Cox regression analysis with time-varying covariates. We performed a sensitivity analysis on a cohort of people with prior colonoscopies, comparing the risk of colon cancer between the diverticulitis group and the control group. Results: We included 29,173 adult males and females with diverticulitis and 145,865 controls matched for sex and age. The incidence proportion of colon cancer was 2.1% (95% confidence interval (CI) 1.9-2.3) in the diverticulitis group and 1.5% (95% CI 1.4-1.5) in the matched control group (hazard ratio 1.6; 95% CI 1.5-1.8). The risk of having a colon cancer diagnosis was significantly increased in the first six months after inclusion (hazard ratio 1.7; 95% CI 1.5-1.8), and hereafter there was a lower risk in the diverticulitis group compared with controls (hazard ratio 0.8; 95% CI 0.7-0.9). This protective effect lasted eight years. The increased risk of colon cancer during the first six months after diverticulitis was also found in the cohort with prior colonoscopies. Conclusions: The risk of a colon cancer diagnosis was significantly increased for patients with diverticulitis 0-6 months after the diagnosis of diverticulitis. Hereafter, we found a protective effect of diverticulitis until eight years later, possibly due to a screening effect. We recommend a follow-up colonoscopy after the first diagnosis of diverticulitis.

Risk of Venous Thromboembolism in Patients With Stage III and IV Non–Small-Cell Lung Cancer: Nationwide Descriptive Cohort Study

BackgroundVenous thromboembolism (VTE) is a common complication in patients starting cancer therapies for non–small-cell lung cancer (NSCLC). We examined the risk and timing of VTE in patients with stage IIIA, IIIB to C, and stage IV NSCLC according to received cancer treatments. Materials and MethodsA nationwide registry-based cohort study of patients recorded in the Danish Lung Cancer Registry (2010-2021) followed for 1 year after entry into the registry to assess the incidence of VTE. The Aalen–Johansen estimator was used to calculate the risk of VTE after treatment commencement with chemotherapy, radiotherapy, chemoradiation, immunotherapy, and targeted therapy. ResultsAmong the 3475 patients with stage IIIA, 4047 with stage IIIB to C, and 18,082 patients with stage IV cancer, the 1-year risk of VTE was highest in the first 6 months and varied markedly by cancer stage and cancer treatment. In stage IIIA, VTE risk was highest with chemotherapy (3.9%) and chemoradiation (4.1%). In stage IIIB to C, risks increased with chemotherapy (5.2%), immunotherapy (9.4%), and targeted therapy (6.0%). Stage IV NSCLC showed high risk with targeted therapy (12.5%) and immunotherapy (12.2%). The risk was consistently higher for pulmonary embolism than deep vein thrombosis. ConclusionVTE risks vary substantially according to cancer treatments and cancer stages. The highest risk was observed in the initial 6 months of therapy initiation. These insights emphasize the need for tailored risk assessment and vigilance in managing VTE complications in patients with NSCLC. Further research is needed to optimize individual thromboprophylaxis strategies for patients with unresectable and metastatic NSCLC.

Pediatric traumatic brain injury and early age multiple sclerosis in Finland: A nationwide register-based cohort study.

Examine the link between pediatric traumatic brain injury (pTBI) and early-onset multiple sclerosis in Finland. Conducted nationwide register study (1998-2018) with 28,750 pTBI patients (<18) and 38,399 pediatric references with extremity fractures. Multiple sclerosis diagnoses from Finnish Social Insurance Institution. Employed Kaplan-Meier and multivariable Cox regression for probability assessment, results presented with 95% CI. Of 66 post-traumatic multiple sclerosis cases, 30 (0.10%) had pTBI, and 36 (0.09%) were in the reference group. Cumulative incidence rates (CIR) in the first 10 years were 46.5 per 100,000 (pTBI) and 33.1 per 100,000 (reference). Hazard ratio (HR) for pTBI was 1.10 (95% CI: 0.56-1.48).Stratified by gender, women's CIR was 197.9 per 100,000 (pTBI) and 167.0 per 100,000 (reference) after 15 years. For men, CIR was 44.6 per 100,000 (pTBI) and 34.7 per 100,000 (reference). In the initial 3 years, HR for female pTBI was 1.75 (95% CI: 0.05-6.32), and between years 3 and 20, it was 1.08 (95% CI: 0.51-1.67). For male patients, HR was 1.74 (95% CI: 0.69-4.39). We did not find evidence of an association between pTBI and early-onset multiple sclerosis 20 years post-initial trauma.

Association of celiac disease with eosinophilic esophagitis: Nationwide register-based cohort study with sibling analyses

Celiac disease (CeD) is associated with several immune-mediated disorders, but it is unclear whether it is associated with eosinophilic esophagitis (EoE). We sought to examine the risk of EoE in patients with biopsy-verified CeD compared with matched controls and siblings. Using nationwide population-based histopathology data, we identified 27,338 patients with CeD diagnosed in the period 2002 to 2017 in Sweden. Patients with CeD were age- and sex-matched with up to 5 reference individuals (n= 134,987) from the general population. Cox Regression was used to estimate hazard ratios (HRs) for developing biopsy-verified EoE. In a secondary analysis, we used unaffected siblings of patients with CeD as comparators to adjust for intrafamilial confounding. The median age at CeD diagnosis was 27 years, and 63.3% were female patients. During a median follow-up of 8.1 years, 17 patients with CeD and 13 matched reference individuals were diagnosed with EoE. This corresponded to incidence rates of 0.08 versus 0.01 per 1000 person-years, respectively, and an adjusted HR for EoE of 6.65 (95% CI, 3.26-13.81). Compared with their siblings without CeD, patients with CeD were however at a no increased risk of EoE (HR, 1.39; 95% CI, 0.55-3.51). In this study, individuals with CeD were at a 6.6-fold increased risk of later EoE compared with the general population. This association might be explained by an altered health-seeking behavior or through shared genetic or early environmental factors because the excess risk disappeared in sibling analyses.

Familial aggregation and heritability of childhood-onset and adult-onset type 1 diabetes: a Swedish register-based cohort study

Type 1 diabetes in children is known to be highly heritable, but much less is known about the heritability of adult-onset type 1 diabetes. Thus, our objective was to compare the familial aggregation and heritability of type 1 diabetes in adults and children. This Swedish nationwide register-based cohort study included individuals born from Jan 1, 1982, to Dec 31, 2010, identified through the Medical Birth Register who were linked to their parents, full siblings, half siblings, and cousins through the Multi-Generation Register (MGR). We excluded multiple births, deaths within the first month of life, individuals who could not be linked to MGR, or individuals with contradictory information on sex. Information on diagnoses of type 1 diabetes was retrieved by linkages to the National Diabetes Register and National Patient Register (1982-2020). Individuals with inconsistent records of diabetes type were excluded. We estimated the cumulative incidence and hazard ratios (HRs) of type 1 diabetes in adults (aged 19-30 years) and children (aged 0-18 years) by family history of type 1 diabetes and the heritability of adult-onset and childhood-onset type 1 diabetes based on tetrachoric correlations, using sibling pairs. 2 943 832 individuals were born in Sweden during the study period, 2 832 755 individuals were included in the analysis of childhood-onset type 1 diabetes and 1 805 826 individuals were included in the analysis of adult-onset type 1 diabetes. 3240 cases of adult-onset type 1 diabetes (median onset age 23·4 years [IQR 21·1-26·2]; 1936 [59·7%] male and 1304 [40·2%] female) and 17 914 cases of childhood-onset type 1 diabetes (median onset age 9·8 years [6·2-13·3]; 9819 [54·8%] male and 8095 [45·2%] female) developed during follow-up. Having a first-degree relative with type 1 diabetes conferred an HR of 7·21 (95% CI 6·28-8·28) for adult-onset type 1 diabetes and 9·92 (9·38-10·50) for childhood-onset type 1 diabetes. The HR of developing type 1 diabetes before the age 30 years was smaller if a first-degree relative developed type 1 diabetes during adulthood (6·68 [6·04-7·39]) rather than during childhood (10·54 [9·92-11·19]). Similar findings were observed for type 1 diabetes in other relatives. Heritability was lower for adult-onset type 1 diabetes (0·56 [0·45-0·66]) than childhood-onset type 1 diabetes (0·81 [0·77-0·85]). Adult-onset type 1 diabetes seems to have weaker familial aggregation and lower heritability than childhood-onset type 1 diabetes. This finding suggests a larger contribution of environmental factors to the development of type 1 diabetes in adults than in children and highlights the need to identify and intervene on such factors. Swedish Research Council, the Swedish Research Council for Health, Working Life and Welfare, Swedish Diabetes Foundation, and the China Scholarship Council.

Adult offspring's education and parental mortality: A nationwide cohort study of the mediating role of lifestyle-related diseases.

Aim: The mechanisms behind the association between adult offspring's socioeconomic position and their parents' mortality are not well understood. This study investigates lifestyle-related diseases as a potential mediating pathway between adult offspring's education and parental mortality. Methods: This nationwide register-based cohort study consists of 963,742 older adults aged 65 years between 2000 and 2018. Lifestyle-related diseases were measured between 60 and 65 years and those with prior lifestyle-related diseases were excluded. Natural Effect Models were performed to assess potential mediation through lifestyle-related diseases of the association between offspring's education and parental mortality measured by additive hazard estimates with 95% confidence intervals (CIs). Results: Between 60 and 65 years, 150,501 (15.6%) older adults were diagnosed with lifestyle-related diseases and 149,647 (15.5%) died during follow-up. Compared with having offspring with long education, short education was associated with 631 (95% CI: 555; 707) and 581 (95% CI: 525; 638) additional deaths per 100,000 person-years for women and men, respectively, of which 15.4% (95% CI: 9.0; 21.6) and 16.8% (95% CI: 14.6; 18.9) were mediated by lifestyle-related diseases. The corresponding numbers for medium education were 276 (95% CI: 205; 347) and 299 (95% CI: 255; 343) with 26.2% (95% CI: 12.0; 40.6) and 27.6% (95% CI: 25.1; 31.8) mediated by lifestyle-related diseases. Conclusions: Lifestyle-related diseases accounted for 15-28% of the association between offspring's education and parental mortality for both men and women.

Attention-Deficit/Hyperactivity Disorder Medications and Work Disability and Mental Health Outcomes

ImportanceIndividuals with attention-deficit/hyperactivity disorder (ADHD) often have comorbid psychiatric conditions. Relatively little is known about how specific ADHD medications are associated with overall treatment outcomes among these patients.ObjectiveTo investigate the association of the use of specific ADHD medications with hospitalization outcomes and work disability among adolescents and adults with ADHD.Design, Setting, and ParticipantsThis nationwide register-based cohort study identified individuals (aged 16-65 years) with ADHD from Swedish nationwide registers of inpatient health care, specialized outpatient health care, sickness absence, and disability pension during the years 2006 to 2021. Data analysis was performed from November 2022 to August 2023.ExposureUse of specific ADHD medications.Main Outcomes and MeasuresThe main outcome measure was psychiatric hospitalization, and secondary outcomes were suicide attempt and/or death by suicide, nonpsychiatric hospitalization, and work disability (ie, sickness absence or disability pension). The risk of outcomes between use vs nonuse periods of ADHD medications was compared in a within-individual design, where a person acts as their own control, and was analyzed with stratified Cox models.ResultsA total of 221 714 persons with ADHD were included in the study cohort (mean [SD] age, 25.0 [11.2] years; 120 968 male individuals [54.6%]). Methylphenidate was the most commonly used ADHD medication (151 837 individuals [68.5%]), followed by lisdexamphetamine (78 106 individuals [35.2%]) during the follow-up (mean [SD], 7.0 [4.7] years). The following medications were associated with a decreased risk of psychiatric hospitalization: amphetamine (adjusted hazard ratio [aHR], 0.74; 95% CI, 0.61-0.90), lisdexamphetamine (aHR, 0.80; 95% CI, 0.78-0.82), ADHD drug polytherapy (aHR, 0.85; 95% CI, 0.82-0.88), dexamphetamine (aHR, 0.88; 95% CI, 0.83-0.94), and methylphenidate (aHR, 0.93; 95% CI, 0.92-0.95). No associations were found for modafinil, atomoxetine, clonidine, and guanfacine. Decreased risk of suicidal behavior was associated with the use of dexamphetamine (aHR, 0.69; 95% CI, 0.53-0.89), lisdexamphetamine (aHR, 0.76; 95% CI, 0.68-0.84), and methylphenidate (aHR, 0.92; 95% CI, 0.86-0.98). None of the medications was associated with increased risk of nonpsychiatric hospitalization; instead, use of amphetamine, lisdexamphetamine, polytherapy, dexamphetamine, methylphenidate, and atomoxetine were associated with decreased risk of nonpsychiatric hospitalization. The results regarding work disability were significant only for the use of atomoxetine (aHR, 0.89; 95% CI, 0.82-0.97), especially among adolescents and young adults aged 16 to 29 years, (aHR, 0.82; 95% CI, 0.73-0.92).Conclusions and RelevanceIn this nationwide cohort study of adolescents and adults with ADHD, the use of ADHD medication was associated with fewer hospitalizations for both psychiatric and nonpsychiatric morbidity and lower suicidal behavior.

Stable glioma incidence and increased patient survival over the past two decades in Norway: a nationwide registry-based cohort study.

Surveillance of incidence and survival of central nervous system tumors is essential to monitor disease burden and epidemiological changes, and to allocate health care resources. Here, we describe glioma incidence and survival trends by histopathology group, age, and sex in the Norwegian population. We included patients with a histologically verified glioma reported to the Cancer Registry of Norway from 2002 to 2021 (N = 7,048). Population size and expected mortality were obtained from Statistics Norway. Cases were followed from diagnosis until death, emigration, or 31 December 2022, whichever came first. We calculated age-standardized incidence rates (ASIR) per 100,000 person-years and age-standardized relative survival (RS). Results: The ASIR for histologically verified gliomas was 7.4 (95% CI: 7.3-7.6) and was higher for males (8.8; 95% CI: 8.5-9.1) than females (6.1; 95% CI: 5.9-6.4). Overall incidence was stable over time. Glioblastoma was the most frequent tumor entity (ASIR = 4.2; 95% CI: 4.1-4.4). Overall, glioma patients had a 1-year RS of 63.6% (95% CI: 62.5-64.8%), and a 5-year RS of 32.8% (95% CI: 31.6-33.9%). Females had slightly better survival than males. For most entities, 1- and 5-year RS improved over time (5-year RS for all gliomas 29.0% (2006) and 33.1% (2021), p < 0.001). Across all tumor types, the RS declined with increasing age at diagnosis. The incidence of gliomas has been stable while patient survival has increased over the past 20 years in Norway. As gliomas represent a heterogeneous group of primary CNS tumors, regular reporting from cancer registries at the histopathology group level is important to monitor disease burden and allocate health care resources in a population.

Cancer risk with tocilizumab/sarilumab, abatacept, and rituximab treatment in patients with rheumatoid arthritis: a Danish cohort study.

To investigate cancer risk in rheumatoid arthritis (RA) patients treated with tocilizumab/sarilumab, abatacept, or rituximab compared with those who received tumour necrosis factor inhibitors (TNFi) and compared with biological disease-modifying anti-rheumatic drugs (bDMARD) naïve RA patients. Nationwide registry-based cohort study of RA patients initiating treatment with tocilizumab/sarilumab, abatacept, rituximab, TNFi, and bDMARD-naive patients their second type of conventional synthetic DMARD (csDMARD). Patients were identified in DANBIO and followed for cancer from 2006-2020. Patients could contribute multiple treatments, with person years (PYRS), deaths, and cancers allocated to each treatment group in a 'latest type of treatment' manner. Inverse probability of treatment weighting and weighted cause-specific Cox models were used to calculate hazard ratios (HRs) for cancer in each tocilizumab/sarilumab, abatacept, and rituximab group compared with TNFI and bDMARD naïve groups, respectively. In total, 21 982 treatment initiations, 96 475 PYRS, and 1423 cancers were identified. There were no statistically significant increased HRs for overall cancer in tocilizumab/sarilumab, abatacept, or rituximab treatment groups (HRs ranged from 0.7-1.1). More than five years of abatacept exposure showed a non-significantly increased HR compared with TNFi (HR 1.41, 95% confidence intervals CI 0.74-2.71). For hematological cancers, rituximab treatment showed non-significantly reduced HRs: vs TNFi (HR 0.09; 95%CI 0.00-2.06) and bDMARD-naïve (HR 0.13; 95%CI 0.00-1.89). Treatment with tocilizumab/sarilumab, abatacept, or rituximab in RA patients was not associated with increased risks of cancer compared with TNFi-treated and with bDMARD-naïve RA patients in a real-world setting.

Abstract A108: Aspirin and non-steroidal anti-inflammatory medication and survival following an ovarian cancer diagnosis: A Norwegian nationwide registry-based cohort study

Abstract A108: Aspirin and non-steroidal anti-inflammatory medication and survival following an ovarian cancer diagnosis: A Norwegian nationwide registry-based cohort study

Prevalence and impact of SARS-CoV-2 infection among patients with acute ischaemic stroke: a nationwide register-based cohort study in Denmark

ObjectivesAn increased risk of stroke has been reported among patients with COVID-19 caused by SARS-CoV-2. We aimed to investigate the nationwide prevalence of SARS-CoV-2 among patients with acute ischaemic stroke...

How valid is a prescription-based multimorbidity index (Rx-risk) in predicting mortality in the Outcomes and Multimorbidity In Type 2 diabetes (OMIT) study? A nation-wide registry-based cohort study from Norway

ObjectiveThe prescription-based Rx-risk index has previously been developed to measure multimorbidity. We aimed to adapt and evaluate the validity of the Rx-risk index in prediction of mortality among persons with...

Characteristics associated with non-initiation and non-completion of human papillomavirus vaccination among Danish girls: a nationwide register-based cohort study.

The aim was to identify maternal and paternal socioeconomic and demographic characteristics for non-initiation and non-completion of the human papillomavirus (HPV) vaccination among Danish girls including time-trends. This nationwide register-based cohort study included all girls residing in Denmark who were offered free-of-charge HPV vaccination as a part of the childhood vaccination program between 2009 and 2018 (birth cohorts 1996-2005). The study samples included 296,461 daughter-mother dyads and 291,025 daughter-father dyads. Data from the Danish Vaccination Register were linked with socioeconomic and demographic data from Statistics Denmark. HPV vaccination status was classified as 'non-initiation' for girls who received no HPV vaccine and as 'non-completion' for girls who initiated the HPV vaccination program but did not receive all the scheduled HPV vaccines. Data were analyzed using logistic regression models. Non-initiation of HPV vaccination was 13.7%, and non-completion was 24.2% among girls who initiated the HPV vaccination program. Girls of parents who were descendants of immigrants (adjusted odds ratio: 1.50; 95% confidence interval: 1.35-1.68), were at least 35-years old at time of birth, had basic or no education, had a low income, were not in the labor market, and were unmarried had the highest non-initiation and non-completion odds. The associations between socioeconomic and demographic characteristics and HPV vaccination uptake were similar for mothers and fathers. Despite free-of-charge availability to HPV vaccination in Denmark, we found disparities in non-initiation and non-completion of HPV vaccination among Danish girls by both mothers' and fathers' socioeconomic and demographic characteristics.

Incident Cardiovascular Disease in Women With Type 1 or Type 2 Diabetes Following a Hypertensive Disorder of Pregnancy.

The extent to which a history of hypertensive disorders of pregnancy is associated with incident cardiovascular disease also among women with diabetes is unknown. In this nationwide register-based cohort study, parous women aged 18 to 69 years with a first delivery in the Swedish Medical Birth Register, regardless of diabetic status at that time, and a subsequent clinical visit in the Swedish National Diabetes Register were included. Time to first cardiovascular disease event (myocardial infarction, stroke, or heart failure) before age 70 years by hypertensive disorders of pregnancy history was separately analyzed by diabetes type using Cox regression models that included conventional risk factors. In total, 1748 (18.9%) of 9230 women with type 1 and 5904 (10.6%) of 55 773 women with type 2 diabetes had their first delivery complicated by a hypertensive disorder of pregnancy. Median time (25-75th percentile) between first delivery and start of follow-up was 3.3 (1.4-13.0) years for women with type 1 and 29.8 (22.4-35.6) years for women with type 2 diabetes. In modeling, the risk for any cardiovascular disease event among women with a history of hypertensive disorders of pregnancy was generally 10% to 20% higher, with main models estimating hazard ratios to 1.20 (95% CI, 0.99-1.47) for women with type 1 and 1.15 (95% CI, 1.02-1.29) for women with type 2 diabetes. In women with diabetes, a history of hypertensive disorders of pregnancy was associated with an increased risk of incident cardiovascular disease and should be considered as a risk enhancer.