Mortality, neurodevelopmental impairments, and economic outcomes after invasive group B streptococcal disease in early infancy in Denmark and the Netherlands: a national matched cohort study

Background

Group B Streptococcus (GBS) disease is a leading cause of neonatal death, but its long-term effects have not been studied after early childhood. The aim of this study was to assess long-term mortality, neurodevelopmental impairments (NDIs), and economic outcomes after infant invasive GBS (iGBS) disease up to adolescence in Denmark and the Netherlands.

Methods

For this cohort study, children with iGBS disease were identified in Denmark and the Netherlands using national medical and administrative databases and culture results that confirmed their diagnoses. Exposed children were defined as having a history of iGBS disease (sepsis, meningitis, or pneumonia) by the age of 89 days. For each exposed child, ten unexposed children were randomly selected and matched by sex, year and month of birth, and gestational age. Mortality data were analysed with the use of Cox proportional hazards models. NDI data up to adolescence were captured from discharge diagnoses in the National Patient Registry (Denmark) and special educational support records (the Netherlands). Health care use and household income were also compared between the exposed and unexposed cohorts.

Findings

2258 children—1561 in Denmark (born from Jan 1, 1997 to Dec 31, 2017) and 697 in the Netherlands (born from Jan 1, 2000 to Dec 31, 2017)—were identified to have iGBS disease and followed up for a median of 14 years (IQR 7–18) in Denmark and 9 years (6–11) in the Netherlands. 366 children had meningitis, 1763 had sepsis, and 129 had pneumonia (in Denmark only). These children were matched with 22 462 children with no history of iGBS disease. iGBS meningitis was associated with an increased mortality at age 5 years (adjusted hazard ratio 4·08 [95% CI 1·78–9·35] for Denmark and 6·73 [3·76–12·06] for the Netherlands). Any iGBS disease was associated with an increased risk of NDI at 10 years of age, both in Denmark (risk ratio 1·77 [95% CI 1·44–2·18]) and the Netherlands (2·28 [1·64–3·17]). A history of iGBS disease was associated with more frequent outpatient clinic visits (incidence rate ratio 1·93 [95% CI 1·79–2·09], p<0·0001) and hospital admissions (1·33 [1·27–1·38], p<0·0001) in children 5 years or younger. No differences in household income were observed between the exposed and unexposed cohorts.

Interpretation

iGBS disease, especially meningitis, was associated with increased mortality and a higher risk of NDIs in later childhood. This previously unquantified burden underlines the case for a maternal GBS vaccine, and the need to track and provide care for affected survivors of iGBS disease.

Funding

The Bill & Melinda Gates Foundation.

Translations

For the Dutch and Danish translations of the abstract see Supplementary Materials section.

Arterial Thromboembolism in Cancer Patients: A Danish Population-Based Cohort Study

Background

The relation between cancer and arterial thromboembolism (ATE) remains unclear.

Objectives

The purpose of this study was to evaluate ATE risk in cancer patients.

Methods

Danish registries were used to identify all cancer patients between 1997 and 2017, each matched to three cancer-free comparator individuals. ATE was defined as the composite of myocardial infarction, ischemic/unspecified stroke, and peripheral arterial occlusion. A competing risk approach was used to compute cumulative incidences and subdistribution hazard ratios (SHRs). Cause-specific hazard ratios (HRs) were calculated using Cox regression. Among cancer patients, mortality risk was estimated in Cox regression analysis by treating ATE as a time-varying exposure. Patients were followed for 12 months.

Results

The study included 458,462 cancer patients and 1,375,386 comparator individuals. In the 6-month period following cancer diagnosis/index date, the cumulative incidence for ATE was 1.50% (95% confidence interval [CI]: 1.47% to 1.54%) in cancer patients and 0.76% (95% CI: 0.75% to 0.77%) in comparator individuals (HR: 2.36; 95% CI: 2.28 to 2.44). Among cancer patients age <65 years, 65 to 75 years, and >75 years, this was 0.79% (95% CI: 0.74% to 0.83%), 1.61% (95% CI: 1.55% to 1.67%), and 2.30% (95% CI: 2.22% to 2.38%), respectively. Other predictors for ATE among cancer patients were prior ATE (SHR: 2.96; 95% CI: 2.77 to 3.17), distant metastasis (adjusted SHR: 1.21; 95% CI: 1.12 to 1.30), and chemotherapy (SHR: 1.47; 95% CI: 1.33 to 1.61). Among cancer patients, ATE was associated with an increased risk of mortality (HR: 3.28; 95% CI: 3.18 to 3.38).

Conclusions

Cancer patients are at increased risk of ATE. Clinicians should be aware of this risk, which is associated with mortality.

Association Between Atopic Dermatitis and Educational Attainment in Denmark

IMPORTANCE

Atopic dermatitis (AD) may affect academic performance through multiple pathways, including poor concentration associated with itching, sleep deprivation, or adverse effects of medications. Because educational attainment is associated with health and well-being, any association with a prevalent condition such as AD is of major importance.

OBJECTIVE

To examine whether a childhood diagnosis of AD is associated with lower educational attainment.

DESIGN, SETTING, AND PARTICIPANTS

This population-based cohort study used linked routine health care data from January 1, 1977, to June 30, 2017 (end of registry follow-up), in Denmark. The study population included all children born in Denmark on June 30, 1987, or earlier with an inpatient or outpatient hospital clinic diagnosis of AD recorded before their 13th birthday (baseline) and a comparison cohort of children from the general population matched by birth year and sex. A secondary analysis included exposure-discordant full siblings as a comparison cohort to account for familial factors. Data were analyzed from September 11, 2019, to January 21, 2021.

EXPOSURES

Hospital-diagnosed AD.

MAIN OUTCOMES AND MEASURES

Estimated probability or risk of not attaining specific educational levels (lower secondary, upper secondary, and higher) by 30 years of age among children with AD compared with children in the matched general population cohort. Corresponding risk ratios (RRs) were computed using Poisson regression that was conditioned on matched sets and adjusted for age. The sibling analysis was conditioned on family and adjusted for sex and age.

RESULTS

The study included a total of 61 153 children, 5927 in the AD cohort (3341 male [56.4%]) and 55 226 from the general population (31 182 male [56.5%]). Compared with matched children from the general population, children with AD were at increased risk of not attaining lower secondary education (150 of 5927 [2.5%] vs 924 of 55 226 [1.7%]; adjusted RR, 1.50; 95% CI, 1.26-1.78) and upper secondary education (1141 of 5777 [19.8%] vs 8690 of 52 899 [16.4%]; RR, 1.16; 95% CI, 1.09-1.24), but not higher education (2406 of 4636 [51.9%] vs 18 785 of 35 408 [53.1%]; RR, 0.95; 95% CI, 0.91-1.00). The absolute differences in probability were less than 3.5%. The comparison of 3259 children with AD and 4046 of their full siblings yielded estimates that were less pronounced than those in the main analysis (adjusted RR for lower secondary education, 1.29 [95% CI, 0.92-1.82]; adjusted RR for upper secondary education, 1.05 [95% CI, 0.93-1.18]; adjusted RR for higher education, 0.94 [95% CI, 0.87-1.02]).

CONCLUSIONS AND RELEVANCE

This population-based cohort study found that hospital-diagnosed AD was associated with reduced educational attainment, but the clinical importance was uncertain owing to small absolute differences and possible confounding by familial factors in this study. Future studies should examine for replicability in other populations and variation by AD phenotype.

Latent classes of posttraumatic psychiatric comorbidity in the general population

Some narrow patterns of posttraumatic psychiatric comorbidity are well-established (e.g., posttraumatic stress disorder and substance use). However, broad multi-diagnosis profiles of posttraumatic comorbidity are poorly characterized. The goal of the current study was to use latent class analysis (LCA) to identify profiles of posttraumatic psychopathology from 11 International Classification of Diseases (ICD-10) diagnostic categories (e.g., stress, substance, depressive, psychosis, personality). Danish national registries were used to identify 166,539 individuals (median age = 41 years, range = <1 to >100) who experienced a traumatic event between 1994 and 2016 and were diagnosed with one or more mental disorders within 5 years. Two through 14-class LCA solutions were evaluated. A 13-class solution (a) provided the best fit, with the Bayes and Akaike Information Criteria reaching a minimum, (b) was broadly consistent with prior LCA studies, and (c) included several novel classes reflecting differential patterns of posttraumatic psychopathology. Three classes were characterized by high comorbidity: broad high comorbidity (M # diagnoses = 4.3), depression with stress/substance use/personality/neurotic disorders (M# diagnoses = 3.8), and substance use with personality/stress/psychotic disorders (M # diagnoses = 3.1). The other 10 classes were characterized by distinct patterns of mild comorbidity or negligible comorbidity. Compared to the mild and negligible comorbidity classes, individuals in high comorbidity classes were younger, had lower income, and had more pre-event psychiatric disorders. Results suggest that several different comorbidity patterns should be assessed when studying and treating posttraumatic psychopathology.

Body Mass Index and 90-Day Mortality Among 35,406 Danish Patients Hospitalized for Infection

OBJECTIVE

To examine the association between body mass index (BMI) and mortality after hospitalization for infection because obesity is associated with increased energy reserves that may protect against death from severe infections.

PATIENTS AND METHODS

Of 76,044 patients admitted with a primary infection diagnosis from January 1, 2011, to September 30, 2015, in Central Denmark, we examined a subgroup of 35,406 patients with a known BMI. We compared the 90-day death risk among patients with underweight, overweight, or obesity with a reference cohort of normal-weight patients. We also examined the impact of comorbid conditions, including cancer, tobacco smoking, and recent weight changes, on the associations and adjusted for other potential confounding factors.

RESULTS

The 90-day mortality after hospital admission was 9.8% (3479 of 35,406) for any infection, 10.5% (466 of 4425) for urinary tract infection, 17.3% (1536 of 8855) for pneumonia, 24.9% (986 of 3964) for sepsis, and 6.2% (114 of 1831) for skin infection. The 90-day adjusted hazard ratio (aHR) for death was substantially increased in patients with underweight (aHR, 1.75; 95% CI, 1.58 to 1.94) compared with normal-weight patients. In contrast, mortality aHRs were decreased in patients with overweight (aHR, 0.64; 95% CI; 0.58 to 0.69) and obesity (aHR, 0.55; 95% CI; 0.49 to 0.62). Mortality reductions with overweight and obesity were consistent for all major infection types and remained robust independent of recent weight changes, smoking status, or comorbid conditions. Mortality was highest in patients without an apparent reason for their underweight (smoking/known disease), suggesting a role of undiagnosed comorbid conditions.

CONCLUSION

We found evidence that higher BMI (overweight and obesity) is associated with improved survival following acute hospitalization for infection, whereas underweight increases the risk for death.

Long-Term Survival, Health, Social Functioning, and Education in Patients With an Enterovirus Central Nervous System Infection, Denmark, 1997-2016

BACKGROUND

The long-term clinical course of patients with an enterovirus central nervous system infection (ECI) is poorly understood.

METHODS

We performed a nationwide population-based cohort study of all Danish patients with ECI diagnosed 1997-2016 (n = 1745) and a comparison cohort from the general population individually matched on date of birth and sex (n = 17 450). Outcomes were categorized into mortality and risk of cancer and likely measures of neurological sequelae: neuropsychiatric morbidities, educational landmarks, use of hospital services, employment, receipt of disability pension, income, number of sick leave days, and nursing home residency.

RESULTS

Mortality in the first year was higher among patients with ECI (mortality rate ratio [MRR] = 10.0; 95% confidence interval [CI], 4.17-24.1), but thereafter mortality was not higher (MMR = 0.94; 95% CI, 0.47-1.86). Long-term outcomes for patients with ECI were not inferior to those of the comparison cohort for risk of cancer, epilepsy, mental and behavioral disorders, dementia, depression, school start, school marks, high school education, use of hospital services, employment, receipt of disability pension, income, days of sick leave, or nursing home residency.

CONCLUSIONS

Diagnosis of an ECI had no substantial impact on long-term survival, health, or social/educational functioning.

Outcomes in patients with lung cancer treated with crizotinib and erlotinib in routine clinical practice: A post-authorization safety cohort study conducted in Europe and in the United States

PURPOSE

We examined safety outcomes of interest (SOI) and overall survival (OS) among lung cancer patients initiating crizotinib and erlotinib in routine clinical practice.

METHODS

This descriptive cohort study used routinely collected health data in Denmark, Finland, Sweden, the Netherlands, and the United States (US) during 2011-2017, following crizotinib commercial availability in each country. Among crizotinib or erlotinib initiators, we reported baseline characteristics and incidence rates and cumulative incidences of the SOI - hepatotoxicity, pneumonitis/interstitial lung disease, QT interval prolongation-related events, bradycardia, vision disorders, renal cysts, edema, leukopenia, neuropathy, photosensitivity, malignant melanoma, gastrointestinal perforation, cardiac failure and OS. Results from the European Union (EU) countries were combined using meta-analysis; results from the US were reported separately.

RESULTS

There were 456 patients in the crizotinib cohort and 2957 patients in the erlotinib cohort. Rates of the SOI per 1000 person-years in the crizotinib cohort ranged from 0 to 65 in the EU and from 0 to 374 in the US. Rates of the SOI per 1000 person-years in the erlotinib cohort ranged from 0 to 91 in the EU and from 3 to 394 in the US. In the crizotinib cohort, 2-year OS was ~50% in both EU and US. In the erlotinib cohort, 2-year OS was 21% in the EU and 35% in the US.

CONCLUSIONS

This study describes clinical outcomes among lung cancer patients initiating crizotinib or erlotinib in routine clinical practice. Differences between SOI rates in EU and US may be partially attributable to differences in the underlying databases.

Risk stratification by assessment of coronary artery disease using coronary computed tomography angiography in diabetes and non-diabetes patients: a study from the Western Denmark Cardiac Computed Tomography Registry

AIMS

We examined whether severity of coronary artery disease (CAD) measured by coronary computed tomography angiography can be used to predict rates of myocardial infarction (MI) and death in patients with and without diabetes.

METHODS AND RESULTS

A cohort study of consecutive patients (n = 48 731) registered in the Western Denmark Cardiac Computed Tomography Registry from 2008 to 2016. Patients were stratified by diabetes status and CAD severity (no, non-obstructive, or obstructive). Endpoints were MI and death. Event rates per 1000 person-years, unadjusted and adjusted incidence rate ratios were computed. Median follow-up was 3.6 years. Among non-diabetes patients, MI event rates per 1000 person-years were 1.4 for no CAD, 4.1 for non-obstructive CAD, and 9.1 for obstructive CAD. Among diabetes patients, the corresponding rates were 2.1 for no CAD, 4.8 for non-obstructive CAD, and 12.6 for obstructive CAD. Non-diabetes and diabetes patients without CAD had similar low rates of MI [adjusted incidence rate ratio 1.40, 95% confidence interval (CI): 0.71-2.78]. Among diabetes patients, the adjusted risk of MI increased with severity of CAD (no CAD: reference; non-obstructive CAD: adjusted incidence rate ratio 1.71, 95% CI: 0.79-3.68; obstructive CAD: adjusted incidence rate ratio 4.42, 95% CI: 2.14-9.17). Diabetes patients had higher death rates than non-diabetes patients, irrespective of CAD severity.

CONCLUSION

In patients without CAD, diabetes patients have a low risk of MI similar to non-diabetes patients. Further, MI rates increase with CAD severity in both diabetes and non-diabetes patients; with diabetes patients with obstructive CAD having the highest risk of MI.

Statin Therapy and Risk of Polyneuropathy in Type 2 Diabetes: A Danish Cohort Study

OBJECTIVE

Statins may reduce the risk of diabetic polyneuropathy (DPN) as a result of lipid-lowering and anti-inflammatory effects, but statins have also been associated with neurotoxicity. We examined whether statin therapy affects the risk of DPN.

RESEARCH DESIGN AND METHODS

We identified all Danish patients with incident type 2 diabetes during 2002-2016. New users initiated statins between 180 days before and 180 days after their first diabetes record, while prevalent users had initiated statins before that period. Patients were followed for incident DPN using validated hospital diagnosis codes, starting 180 days after their first diabetes record. Cox proportional hazard analysis was used to compute adjusted hazard ratios (aHRs) for DPN.

RESULTS

The study cohort comprised 59,255 (23%) new users, 75,528 (29%) prevalent users, and 124,842 (48%) nonusers; median follow-up time was 6.2 years (interquartile range 3.4-9.6). The incidence rate of DPN events per 1,000 person-years was similar in new users (4.0 [95% CI 3.8-4.2]), prevalent users (3.8 [3.6-3.9]), and nonusers (3.8 [3.7-4.0]). The aHR for DPN was 1.05 (0.98-1.11) in new users and 0.97 (0.91-1.04) in prevalent users compared with statin nonusers. New users had a slightly increased DPN risk during the first year (1.31 [1.12-1.53]), which vanished after >2 years of follow-up. Findings were similar in on-treatment and propensity score-matched analyses and with additional adjustment for pretreatment blood lipid levels.

CONCLUSIONS

Statin therapy is unlikely to increase or mitigate DPN risk in patients with type 2 diabetes, although a small acute risk of harm cannot be excluded.

Pregravid contraceptive use and fecundability: prospective cohort study

OBJECTIVE

To evaluate the association between pregravid use of a variety of contraceptive methods and subsequent fecundability.

DESIGN

Prospective cohort study.

SETTING

Denmark and North America, 2007-19.

PARTICIPANTS

17 954 women who had tried to conceive for up to six menstrual cycles at study entry. At baseline, participants reported their contraceptive histories, and personal, medical, and lifestyle characteristics.

MAIN OUTCOME MEASURES

Pregnancy, determined by bimonthly follow-up questionnaires for up to 12 months.

RESULTS

Approximately 38% (n=6735) of participants had recently used oral contraceptives, 13% (n=2398) had used long acting reversible contraceptive methods, and 31% (n=5497) had used barrier methods. Women who had recently stopped using oral contraceptives, the contraceptive ring, and some long acting reversible contraceptive methods experienced short term delays in return of fertility compared with users of barrier methods. Use of injectable contraceptives was associated with decreased fecundability compared with use of barrier methods (fecundability ratio 0.65; 95% confidence interval 0.47 to 0.89). Users of injectable contraceptives had the longest delay in return of normal fertility (five to eight menstrual cycles), followed by users of patch contraceptives (four cycles), users of oral and ring contraceptives (three cycles), and users of hormonal and copper intrauterine devices and implant contraceptives (two cycles). Lifetime length of use of hormonal contraceptive methods was not associated with fecundability.

CONCLUSIONS

Use of some hormonal contraceptive methods was associated with delays in return of fertility, with injectable contraceptives showing the longest delay. The findings indicated little or no lasting effect of long term use of these methods on fecundability.

Community-Acquired Escherichia coli Bacteremia after Age 50 and Subsequent Incidence of a Cancer Diagnosis: A Danish Population-Based Cohort Study

BACKGROUND

Community-acquired bacteremia (CAB) with Escherichia coli may signal occult cancer. This might differ between phylogenetic groups.

METHODS

We conducted a population-based cohort study in northern Denmark (1994-2013) to examine whether E. coli CAB after age 50 is associated with incident cancer. We followed patients from their bacteremia diagnosis date to identify subsequent gastrointestinal, hepatobiliary, and urinary tract cancer diagnoses. We calculated 1- and 5-year cumulative cancer incidence. We compared the observed incidence with that expected based on national cancer incidence rates, and computed standardized incidence ratios (SIR) at 0-<1 year and ≥1 year. In a subcohort, we assessed the prevalence of phylogenetic groups.

RESULTS

Among 2,735 patients with E. coli CAB, 173 later were diagnosed with cancer. The 1-year cumulative incidence of a gastrointestinal or hepatobiliary tract cancer was 1.9%, and the 0-<1-year SIR was 5.44 [95% confidence interval (CI), 4.06-7.14]. For urinary tract cancer, the corresponding estimates were 1.0% and 3.41 (95% CI, 2.27-4.93). All individual cancers occurred more often than expected during the first year following E. coli CAB, but thereafter the relative risks declined toward unity. Still, the ≥1-year SIR for colorectal cancer remained 1.4-fold elevated, and the SIR for liver, pancreas, gallbladder, and biliary tract cancer was 2-fold elevated. The prevalence of phylogenetic groups was similar among patients with and without cancer.

CONCLUSIONS

Gastrointestinal, hepatobiliary, and urinary tract cancer may debut with E. coli CAB.

IMPACT

Owing to the high incidence of E. coli bacteremia, cancers missed at the time of bacteremia diagnosis represent a clinically significant problem.

Increased maternal new-onset psychiatric disorders after delivering a child with a major anomaly: a cohort study

BACKGROUND

The birth of a child with a major congenital anomaly may create chronic caregiving stress for mothers, yet little is known about their psychiatric outcomes.

AIMS

To evaluate the association of the birth of a child with a major congenital anomaly with subsequent maternal psychiatric risk.

METHODS

This Danish nationwide cohort study included mothers who gave birth to an infant with a major congenital anomaly (n = 19 220) between 1997 and 2015. Comparators were randomly selected mothers, matched on maternal age, year of delivery and parity (n = 195 399). The primary outcome was any new-onset psychiatric diagnosis. Secondary outcomes included specific psychiatric diagnoses, psychiatric in-patient admissions and redeemed psychoactive medicines. Cox models were used to estimate hazard ratios (HRs), adjusted for socioeconomic and medical variables.

RESULTS

Mothers of affected infants had an elevated risk for a new-onset psychiatric disorder vs. the comparison group (adjusted HR, 1.16, 95% CI 1.11-1.22). The adjusted HR was particularly elevated during the first postpartum year (1.65, 95% CI 1.42-1.90), but remained high for years, especially among mothers of children with multiorgan anomalies (1.37, 95% CI 1.18-1.57). The risk was also elevated for most specific psychiatric diagnoses, admissions and medicines.

CONCLUSIONS

Mothers who give birth to a child with a major congenital anomaly are at increased risk of new-onset psychiatric disorders, especially shortly after birth and for mothers of children with more severe anomalies. Our study highlights the need to screen for mental illness in this high-risk population, as well as to integrate adult mental health services and paediatric care.

Renin-angiotensin system blockers and 1-year mortality in patients with post-operative acute kidney injury

BACKGROUND

Angiotensin-converting enzyme inhibitor (ACE-I) and angiotensin-receptor blocker (ARB) users may be associated with increased mortality in patients with post-operative acute kidney injury (AKI), but data are limited. We studied whether users of ACE-I/ARBs with AKI after colorectal cancer surgery (CRC) were associated with increased 1-year mortality after AKI.

METHODS

This population-based cohort study in Northern Denmark included patients with AKI within 7 days after CRC surgery during 2005-2014. From reimbursed prescriptions, patients were classified as ACE-I/ARB current, former, or non-users. We computed the cumulative 30-day and 1-year mortality after AKI with 95% confidence intervals (95% CI) using the Kaplan-Meier method (1-survival function). Hazard ratios (HRs) comparing mortality in current and former users with non-users were computed by Cox proportional hazards regression analyses, controlling for potential confounders.

RESULTS

We identified 10 713 CRC surgery patients. A total of 2000 patients had AKI and were included. Thirty-day mortality was 16.5% (95% CI 13.7-19.8), 16.2% (95% CI 11.3-22.8), and 13.4% (95% CI 11.6-15.4) for current, former, and non-users. Adjusted HR was 1.26 (95% CI 0.96-1.65) and 1.19 (95% CI 0.78-1.82) for current and former users compared with non-users. One-year mortality rates were 26.4% (95% CI 22.9-30.4), 29.8% (95% CI 23.2-37.8), and 24.7% (95% CI 22.4-27.2) in current, former, and non-users. Compared with non-users, the adjusted 1-year HR for death in current and former users were 1.29 (95% CI 0.96-1.73) and 1.11 (95% CI 0.91-1.35).

CONCLUSION

Based on our findings, current users of ACE-I/ARB may possibly have a small increase in mortality rate in the year after post-operative AKI, although the degree of certainty is low.

Association of Neighborhood Disadvantage With Cardiovascular Risk Factors and Events Among Refugees in Denmark

IMPORTANCE

Refugees are among the most disadvantaged individuals in society, and they often have elevated risks of cardiovascular risk factors and events. Evidence is limited regarding factors that may worsen cardiovascular health among this vulnerable group.

OBJECTIVE

To test the hypothesis that refugee placement in socioeconomically disadvantaged neighborhoods is associated with increased cardiovascular risk.

DESIGN, SETTING, AND PARTICIPANTS

The study population of this quasi-experimental, registry-based cohort study included 49 305 adults 18 years and older who came to Denmark as refugees from other countries during the years of Denmark's refugee dispersal policy from 1986 to 1998. Refugees were dispersed to neighborhoods with varying degrees of socioeconomic disadvantage in an arbitrary manner conditional on observed characteristics. The association of neighborhood disadvantage on arrival with several cardiovascular outcomes in subsequent decades was evaluated using regression models that adjusted for individual, family, and municipal characteristics. Health outcomes were abstracted from the inpatient register, outpatient specialty clinic register, and prescription drug register through 2016. Data analysis was conducted from May 2018 to July 2019.

EXPOSURES

A composite index of neighborhood disadvantage was constructed using 8 neighborhood-level socioeconomic characteristics derived from Danish population register data.

MAIN OUTCOMES AND MEASURES

Primary study outcomes included hypertension, hyperlipidemia, type 2 diabetes, myocardial infarction, and stroke. Before data analysis commenced, it was hypothesized that higher levels of neighborhood disadvantage were associated with an increased risk of cardiovascular risk factors and events.

RESULTS

A total of 49 305 participants were included (median [interquartile range] age, 30.5 [24.9-39.8] years; 43.3% women). Participant region of origin included 6318 from Africa (12.8%), 7253 from Asia (14.7%), 3446 from Eastern Europe (7.0%), 5416 from Iraq (11.0%), 6206 from Iran (12.6%), 5558 from Palestine (via Lebanon, Israel, Occupied Palestinian Territories; 11.3%), and 15 108 from Yugoslavia (30.6%). Adjusted models revealed an association between placement in disadvantaged neighborhoods and increased risk of hypertension (0.71 [95% CI, 0.30-1.13] percentage points per unit of disadvantage index; P < .01), hyperlipidemia (0.44 [95% CI, 0.06-0.83] percentage points; P = .01), diabetes (0.45 [95% CI, 0.09-0.81] percentage points; P = .01), and myocardial infarction (0.14 [95% CI, 0.03-0.25] percentage points; P = .01). No association was found for stroke. Individuals who arrived in Denmark before age 35 years had an increased risk of hyperlipidemia (1.16 [95% CI, 0.41-1.92] percentage points; P < .01), and there were no differences by sex.

CONCLUSIONS AND RELEVANCE

In this quasi-experimental cohort study, neighborhood disadvantage was associated with increased cardiovascular risk in a relatively young population of refugees. Neighborhood characteristics may be an important consideration when refugees are placed by resettlement agencies and host countries. Future work should examine additional health outcomes as well as potential mediating pathways to target future interventions (eg, neighborhood ease of walking, employment opportunities).

Long-Term Survival, Morbidity, Social Functioning and Risk of Disability in Patients with a Herpes Simplex Virus Type 1 or Type 2 Central Nervous System Infection, Denmark, 2000-2016

Background

The long-term prognosis following herpes simplex virus (HSV) central nervous system (CNS) infection is still debated.

Patients and Methods

We examined outcomes in all Danish residents who, during 2000–2016, tested PCR positive for HSV-1 (n=208) or HSV-2 (n=283) in the cerebrospinal fluid, compared to comparison cohorts from the general population (n=2080 and n=2830).

Results

One-year mortality was increased among HSV-1 patients (difference 19.3%; 95% CI: 13.6% to 25.0%) and HSV-2 patients (difference 5.3%; 95% CI: 2.5% to 8.1%), but thereafter mortality was not increased. After exclusion of persons diagnosed with cancer prior to study inclusion, one-year mortality difference for HSV-2 patients was 1.7% (−0.1% to 3.5%). After five years, HSV-1 patients had lower employment (difference −19.8%; 95% CI: −34.7% to −4.8%) and higher disability pension rates (difference 22.2%; 95% CI: 8.4% to 36.0%) than the comparison cohort, but similar number of inpatient days, outpatient visits, and sick leave. HSV-2 patients had employment and disability pension rates comparable to the comparison cohort, but more inpatient days (difference 1.5/year; 95% CI: −0.2 to 3.2), outpatient visits (difference 1.3/year; 95% CI: 0.3 to 3.2), and sick leave days (difference 9.1/year; 95% CI: 7.9 to 10.4).

Conclusion

HSV-1 and HSV-2 CNS infections differ substantially with respect to prognosis. HSV-1 CNS infection is followed by increased short-term mortality and long-term risk of disability. HSV-2 CNS infection has no substantial impact on mortality or working capability but is associated with increased morbidity.

Inflammatory bowel disease and pancreatic cancer: a Scandinavian register-based cohort study 1969-2017

BACKGROUND

Patients with inflammatory bowel disease (IBD) have an increased risk of cancer.

AIM

To assess the risk of pancreatic cancer in IBD compared to the general population.

METHODS

Patients with incident IBD 1969-2017 were identified in Danish and Swedish National Patient Registers and through biopsy data, and were matched to IBD-free reference individuals by sex, age, place of residence and year of IBD diagnosis. We linked data to Cancer and Causes of Death Registers and examined the absolute and relative risks of pancreatic cancer and pancreatic cancer death.

RESULTS

Among 161 926 patients followed for 2 000 951 person years, 442 (0.27%) were diagnosed with pancreatic cancer compared to 3386 (0.21%) of the 1 599 024 reference individuals. The 20-year cumulative incidence was 0.34% (95% confidence interval 0.30-0.38) vs 0.29% (0.28-0.30). The incidence rate was 22.1 (20.1-24.2)/100 000 person years in the patients (excluding the first year of follow-up: 20.8 [18.8-23.0]), and 16.6 (16.0-17.2) in the reference individuals. The hazard ratio (HR) for pancreatic cancer was increased overall: 1.43 (1.30-1.58), in subtypes (Crohn's disease: 1.44 [1.18-1.74]; ulcerative colitis: 1.35 [1.19-1.53]; IBD unclassified: 1.99 [1.50-2.64]) and especially in IBD patients with primary sclerosing cholangitis: 7.55 (4.94-11.5). Patients and reference individuals with pancreatic cancer did not differ in cancer stage (P = 0.17) or pancreatic cancer mortality (HR 1.07 [0.95-1.21]).

CONCLUSIONS

Patients with IBD had an excess risk of pancreatic cancer, in particular patients with primary sclerosing cholangitis. However, the cumulative incidence difference after 20 years was small: 0.05%, that is, one extra pancreatic cancer per 2000 IBD patients.

Using negative control outcomes to assess the comparability of treatment groups among women with osteoporosis in the United States

PURPOSE

In contrast to randomized clinical trials, comparative safety and effectiveness assessments of osteoporosis medications in clinical practice may be subject to confounding by indication. We used negative control outcomes to detect residual confounding when comparing osteoporosis medications.

METHODS

Using MarketScan Commercial and Supplemental claims, we identified women aged ≥55 years who initiated an oral bisphosphonate (BP) (risedronate, alendronate, or ibandronate), denosumab (an injected biologic), or intravenous zoledronic acid (ZA) from October 1, 2010 to September 30, 2015. Women with Paget's disease or cancer were excluded. We compared individual oral BPs to each other, denosumab to ZA, denosumab to oral BPs, and ZA to oral BPs, with respect to 11 negative control outcomes identified by subject matter experts. We estimated the 12-month cumulative risk difference (RD) using inverse probability of treatment and censoring weights.

RESULTS

Among 148 587 women, most initiated alendronate (57%), followed by ibandronate (12%), ZA (11%), risedronate (10%), and denosumab (10%). Compared with denosumab, patients initiating ZA had similar risks of all negative control outcomes. Compared with oral BPs, patients initiating denosumab had a higher risk of a wellness visit (RD = 1.2%, 95% CI: 0.4, 1.9) and a lower risk of receiving herpes zoster vaccine (RD = -0.6%, 95% CI: -1.1, -0.2). Comparing ZA with oral BP initiators resulted in two outcomes with positive associations.

CONCLUSIONS

Caution is warranted when comparing injectable vs oral osteoporosis medications, given the potential for unmeasured confounding. Evaluating negative control outcomes could be a standard validity check prior to conducting comparative studies.

Metabolic Factors, Lifestyle Habits, and Possible Polyneuropathy in Early Type 2 Diabetes: A Nationwide Study of 5,249 Patients in the Danish Centre for Strategic Research in Type 2 Diabetes (DD2) Cohort

OBJECTIVE

To investigate the association of metabolic and lifestyle factors with possible diabetic polyneuropathy (DPN) and neuropathic pain in patients with early type 2 diabetes.

RESEARCH DESIGN AND METHODS

We thoroughly characterized 6,726 patients with recently diagnosed diabetes. After a median of 2.8 years, we sent a detailed questionnaire on neuropathy, including the Michigan Neuropathy Screening Instrument questionnaire (MNSIq), to identify possible DPN (score ≥4) and the Douleur Neuropathique en 4 Questions (DN4) questionnaire for possible associated neuropathic pain (MNSIq ≥4 + pain in both feet + DN4 score ≥3).

RESULTS

Among 5,249 patients with data on both DPN and pain, 17.9% (n = 938) had possible DPN, including 7.4% (n = 386) with possible neuropathic pain. In regression analyses, central obesity (waist circumference, waist-to-hip ratio, and waist-to-height ratio) was markedly associated with DPN. Other important metabolic factors associated with DPN included hypertriglyceridemia ≥1.7 mmol/L, adjusted prevalence ratio (aPR) 1.36 (95% CI 1.17; 1.59); decreased HDL cholesterol <1.0/1.2 mmol/L (male/female), aPR 1.35 (95% CI 1.12; 1.62); hs-CRP ≥3.0 mg/L, aPR 1.66 (95% CI 1.42; 1.94); C-peptide ≥1,550 pmol/L, aPR 1.72 (95% CI 1.43; 2.07); HbA_1c ≥78 mmol/mol, aPR 1.42 (95% CI 1.06; 1.88); and antihypertensive drug use, aPR 1.34 (95% CI 1.16; 1.55). Smoking, aPR 1.50 (95% CI 1.24; 1.81), and lack of physical activity (0 vs. ≥3 days/week), aPR 1.61 (95% CI 1.39; 1.85), were also associated with DPN. Smoking, high alcohol intake, and failure to increase activity after diabetes diagnosis associated with neuropathic pain.

CONCLUSIONS

Possible DPN was associated with metabolic syndrome factors, insulin resistance, inflammation, and modifiable lifestyle habits in early type 2 diabetes.

Cancer and risk of Alzheimer's disease: Small association in a nationwide cohort study

INTRODUCTION

Small observational studies with short-term follow-up suggest that cancer patients are at reduced risk of Alzheimer's disease (AD) compared to the general population.

METHODS

A nationwide cohort study using Danish population-based health registries (1980-2013) with cancer patients (n = 949,309) to identify incident diagnoses of AD. We computed absolute reductions in risk attributed to cancer and standardized incidence rate ratios (SIRs) accounting for survival time, comparing the observed to expected number of AD cases.

RESULTS

During up to 34 years of follow-up of cancer survivors, the attributable risk reduction was 1.3 per 10,000 person-years, SIR = 0.94 (95% confidence interval 0.92-0.96). SIRs were similar after stratification by sex, age, and cancer stage, and approached that of the general population for those surviving >10 years.

DISCUSSION

Inverse associations between cancer and AD were small and diminished over time. Incidence rates in cancer survivors approached those of the general population, suggesting limited association between cancer and AD risk.

Hospital-diagnosed overweight and obesity related to cancer risk: a 40-year Danish cohort study

BACKGROUND

Obesity is associated with metabolic abnormalities that predispose patients to increased cancer risk. Contemporary data on the long-term risk of specific cancers are sparse among patients with hospital-diagnosed overweight and obesity.

OBJECTIVES

To examine the overall cancer incidence and specific site-related cancer incidences among patients with overweight and obesity, compared to the general Danish population.

METHODS

For this 40-year (1977-2016), nationwide, Danish cohort study, we reviewed medical databases to identify individuals with hospital-based overweight and obesity diagnoses. We computed age- and gender-standardized incidence ratios (SIRs) for subsequent cancer compared to the general population.

RESULTS

We observed 20 706 cancers among 313 321 patients diagnosed with overweight and obesity (median age 43 years; median follow-up 6.7 years, range 1-40 years) compared to the 18 480 cancers expected; thus, the SIR was 1.12 [95% confidence interval (95% CI): 1.11-1.14]. The SIR associated with overweight and obesity was increased with concomitant comorbidities, like type 2 diabetes (SIR: 1.18; 95% CI: 1.13-1.23) and alcoholism-related diseases (SIR: 1.62; 95% CI: 1.45-1.82). The SIR was 1.31 (95% CI: 1.28-1.34) for cancers previously identified as obesity-related, including pancreatic (SIR: 1.38; 95% CI; 1.27-1.49) and postmenopausal breast cancer (SIR: 1.14; 95% CI: 1.09-1.19). Obesity/overweight status also elevated the SIRs for haematological (SIR: 1.24; 95% CI: 1.18-1.29) and neurological cancers (SIR: 1.19; 95% CI: 1.11-1.27]. In contrast, SIRs were 1.01 (95% CI: 0.97-1.05) for immune-related cancers, 0.88 (95% CI: 0.82-0.95) for malignant melanoma, and 0.88 (95% CI: 0.85-0.92) for hormone-related cancers, other than postmenopausal breast cancer.

CONCLUSION

In this large cohort study, overweight and obesity was associated with increased risk of several common cancers.

Changes in SGLT2i and GLP-1RA real-world initiator profiles following cardiovascular outcome trials: A Danish nationwide population-based study

BACKGROUND

We investigated changes in clinical characteristics of SGLT2i and GLP-1RA real-world initiators in Denmark before/after landmark cardiovascular outcome trials.

METHODS

We compared first-time SGLT2i (25,070) and GLP-1RA (14,671) initiators to initiators of DPP-4i (n = 34,079), a class without proven cardiovascular benefits. We used linked population-based healthcare data to examine initiation incidence, medication patterns, and pre-existing atherosclerotic cardiovascular disease (ASCVD) during 2014-2017.

RESULTS

Nationwide incidence of SGLT2i initiators increased 3.6-fold (53/100,000 to 172/100,000 per year) vs. a 1.5-fold increase for GLP-1RA. DPP-4i initiation remained stable. From the end of 2015, SGLT2i was increasingly used as 2nd-line therapy, while medication patterns were much more stable for GLP-1RA. Among SGLT2i users, ASCVD increased slightly from 28% to 30%; age- and gender-adj. prevalence ratio (aPR) = 1.03 (95% CI:0.97-1.10). In contrast, among GLP-1RA initiators, baseline ASCVD declined from 29% to 27% (aPR: 0.90 (95% CI:0.84-0.97)), and in DPP-4i initiators from 31% to 29% (aPR: 0.91 (95% CI:0.88-0.96)).

CONCLUSIONS

Following the EMPA-REG OUTCOME trial in 2015, SGLT2i have become increasingly used as 2nd-line treatment in everyday clinical practice, with only minor increases in patient proportions with ASCVD. For GLP-1RA, we observed more stable therapy lines and slightly decreasing ASCVD in new users despite the LEADER trial.

Metabolic Pathway Analysis and Effectiveness of Tamoxifen in Danish Breast Cancer Patients

BACKGROUND

Tamoxifen and its metabolites compete with estrogen to occupy the estrogen receptor. The conventional dose of adjuvant tamoxifen overwhelms estrogen in this competition, reducing breast cancer recurrence risk by nearly half. Phase I metabolism generates active tamoxifen metabolites, and phase II metabolism deactivates them. No earlier pharmacogenetic study has comprehensively evaluated the metabolism and transport pathways, and no earlier study has included a large population of premenopausal women.

METHODS

We completed a cohort study of 5,959 Danish nonmetastatic premenopausal breast cancer patients, in whom 938 recurrences occurred, and a case-control study of 541 recurrent cases in a cohort of Danish predominantly postmenopausal breast cancer patients, all followed for 10 years. We collected formalin-fixed paraffin-embedded tumor blocks and genotyped 32 variants in 15 genes involved in tamoxifen metabolism or transport. We estimated conventional associations for each variant and used prior information about the tamoxifen metabolic path to evaluate the importance of metabolic and transporter pathways.

RESULTS

No individual variant was notably associated with risk of recurrence in either study population. Both studies showed weak evidence of the importance of phase I metabolism in the clinical response to adjuvant tamoxifen therapy.

CONCLUSIONS

Consistent with prior knowledge, our results support the role of phase I metabolic capacity in clinical response to tamoxifen. Nonetheless, no individual variant substantially explained the modest phase I effect on tamoxifen response.

IMPACT

These results are consistent with guidelines recommending against genotype-guided prescribing of tamoxifen, and for the first time provide evidence supporting these guidelines in premenopausal women.

Anti-TNF treatment during pregnancy and birth outcomes: A population-based study from Denmark, Finland, and Sweden

PURPOSE

To study the risk of preterm birth, caesarean section, and small for gestational age after anti-tumor necrosis factor agent treatment (anti-TNF) in pregnancy.

METHODS

Population-based study including women with inflammatory bowel disease, rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis, and psoriasis, and their infants born 2006 to 2013 from the national health registers in Denmark, Finland, and Sweden. Women treated with anti-TNF were compared with women with nonbiologic systemic treatment. Adalimumab, etanercept, and infliximab were compared pairwise. Continuation of treatment in early pregnancy was compared with discontinuation. Odds ratios with 95% confidence intervals were calculated in logistic regression models adjusted for country and maternal characteristics.

RESULTS

Among 1 633 909 births, 1027 infants were to women treated with anti-TNF and 9399 to women with nonbiologic systemic treatment. Compared with non-biologic systemic treatment, women with anti-TNF treatment had a higher risk of preterm birth, odds ratio 1.61 (1.29-2.02) and caesarean section, 1.57 (1.35-1.82). The odds ratio for small for gestational age was 1.36 (0.96-1.92). In pairwise comparisons, infliximab was associated with a higher risk of severely small for gestational age for inflammatory joint and skin diseases but not for inflammatory bowel disease. Discontinuation of anti-TNF had opposite effects on preterm birth for inflammatory bowel disease and inflammatory joint and skin diseases.

CONCLUSIONS

Anti-TNF agents were associated with increased risks of preterm birth, caesarean section, and small for gestational age. However, the diverse findings across disease groups may indicate an association related to the underlying disease activity, rather than to agent-specific effects.