Danish National Hospital Register Research Articles

Diagnoses of obstetric and postpartum thyroid disease: a Danish validation study

Different diagnoses of thyroid disease are available in the 10th International Classification of Diseases (ICD-10), but the validity of diagnoses related to obstetric and postpartum thyroid disease is unknown. This was a retrospective cohort study of all patients in the North Denmark Region with a diagnosis of postpartum thyroiditis (PPT) (ICD-10: O905) from 2016 to 2019 or obstetric thyroid disease in 2019 (ICD-10: O992B (hypothyroidism) or O992C (hyperthyroidism)) registered in the Danish National Hospital Register. Information from nationwide registers and medical records were used to assess the validity. Among patients with an O905-diagnosis (n = 40), abnormal thyroid function test results were seen in all cases. A total of eight patients (20.0%) were positive for thyrotropin receptor antibodies postpartum, however, in low titers, and PPT was verified in 39 of 40 cases (97.5%). Altogether 45 of 50 patients with an O992B-diagnosis (90.0%) correctly had hypothyroidism, whereas hyperthyroidism was found in 25 of 39 patients with an O992C-diagnosis (64.1%). This is the first study to validate ICD-10 diagnoses of obstetric and postpartum thyroid disease. A high validity was seen for PPT (O905) and obstetric hypothyroidism (O992B), whereas for obstetric hyperthyroidism (O992C), the diagnosis could not be verified in one third of the cases.

T214. ANTIPSYCHOTIC TREATMENT PATTERNS AND EFFECTS DURING THE EARLY YEARS AMONG 316 NEWLY DIAGNOSED PATIENTS WITH SCHIZOPHRENIA FROM THE OPUS TRIAL

BackgroundIn studies investigating the relapse rate of psychotic symptoms in patients diagnosed with schizophrenia there is a discrepancy between discontinuation studies finding a relapse rate up to 90% after discontinuation of antipsychotic medication and long-term follow-up studies finding approx. 30% of patients living without antipsychotic medication and psychotic symptoms. Long-term follow-up studies often have multiple follow-up assessments, but little is known about the use of medication in the intervals between the follow-up points. While register studies can follow large cohorts of patients, they are unable to investigate psychopathology and level of functioning in patients who discontinue their medication. In this study we use data from a clinical cohort with information on participants symptoms and functioning and combine them with register data on the individual participants prescriptions and hospitalizations.MethodsThe present study represents a combination of a clinical study from early intervention settings and register-based information on antipsychotic drug use and hospital contacts. For the present study, patients were included 18 months into their 24 months early intervention treatment and followed up 3 ½ year later. At baseline and follow-up we performed clinical assessments with all patients and via the Danish National Hospital Register and the Danish National Prescription Register, we had complete nationwide information for all patients identifying all redeemed prescriptions for antipsychotic drugs from 6 to 42 months after inclusion into the study. Based on medication information from the Danish National Prescription Register, we divided participants in the following four groups: 1) Non-users, 2) compliant on medication, 3) stopped but resumed later with medication, and 4) stopped with medication.ResultsOf the 316 participants included in this study 94.3% had I diagnosis of schizophrenia. In the 3 years preceding the 5 years follow-up 28.2% did not redeem any prescriptions for antipsychotics drugs while 21.2% discontinued their treatment during the follow-up, 20.9% discontinued their treatment but resumed later and 29.7% remained in stable treatment. At the 5 years follow-up the 30.3% of the Never-users where in competitive employment, the mean psychotic symptom score were 1.4 SD (1.4) and negative symptoms 1.1 SD (0.9). Whiles these results were worse for patients Compliant on medication (17%, 1.9 SD (1.3), 1.8 SD (1.0)), Stopped but resumed medication (10.6%, 22.4 SD (1.4), 1.5 SD (1.0)) and Stopped medication (17%, 1.6 SD (1.3), 1.3 SD (1.0)), respectively. Of the Never-user 23.6% were in remission of both positive and negative symptoms, while this was only the case for 12.8% of those compliant on medication.DiscussionThis study is a naturalistic cohort study and we are unable to draw any conclusion regarding the causality between symptoms remission and use of antipsychotic medication. The study shows that a substantial proportion of patients, for several years, can discontinue their medical treatment without being re-hospitalized and with lower symptoms burden then patients who continue their medical treatment. Some patients discontinue their treatment but resume it later. These patients have approximately the same functional level and psychotypological scores as those who are compliant with their medical treatment and are treated with equivalent doses of antipsychotic at the time of the follow-up.

The epidemiology of infective endocarditis with focus on non-device related right-sided infective endocarditis: A retrospective register-based study in the region of Southern Denmark

AimsNon-device related right-sided infective endocarditis (ND-RSIE) is not well characterized. We aimed to characterize patients with infective endocarditis (IE) with emphasis on the epidemiology, clinical characteristics and complications of ND-RSIE. MethodsIn this population-based cohort study, we identified patients with IE using ICD-10 codes from the Danish National Hospital Register in the Region of Southern Denmark between January 2007 and May 2017. Hospital records were reviewed, and characteristics and outcomes recorded. ResultsWe included 1243 confirmed IE episodes of which 82% were left-sided IE, 11% were cardiac device right sided infective endocarditis (RSIE) and 7% were ND-RSIE. Patients with ND-RSIE were considerably younger, had less comorbidity and had a lower 30-day mortality (6%) compared with patients with device RSIE (24%) and left-sided IE (26%) (p<0.01). ND-RSIE was associated with underlying heart disease, involvement of the tricuspid valve (57%), Staphylococcus species (53%) and complications (61%). Forty percent of ND-RSIE occurred among people who inject drugs (PWID) for whom significant differences were observed compared with non-PWID with regards to tricuspid valve involvement (96% vs. 32%), causative microorganisms (Staphylococcus aureus 79% vs. 27%), complications (86% vs. 45%), recurrence (29% vs. 11%) and 30-day mortality (0% vs. 7%). ConclusionND-RSIE is relatively rare and differs with regards to epidemiology, clinical characteristics and complications compared with left-sided IE and cardiac device RSIE, but has a favourable prognosis. Forty percent of ND-RSIE occurs among PWID, which is associated with frequent complications but a very low mortality.

Recurrence of Cholesteatoma - A Retrospective Study Including 1,006 Patients for More than 33 Years.

Introduction Cholesteatomas are benign tumors consisting of skin, and growing inside a retraction pocket in the tympanic membrane. Cholesteatomas can occupy the entirety of the middle ear, and are known for their osteolytic capabilities. Surgery is the only curative treatment for cholesteatomas. Objective To describe the risk of recurrence after first-time surgically-treated middle-ear cholesteatoma (STMEC1) on the island of Funen from 1983 to 2015. Methods Cases of STMEC1 were identified in the Danish National Hospital Register. The medical records were reviewed. Time-to-event analyses were applied. The ears were followed from STMEC1 to a secondary cholesteatoma, emigration, death, or end of follow-up. Results Records from 1,006 patients with STMEC1 were reviewed. A total of 54 patients were submitted to surgery on both ears. The total sample consisted of 1,060 ears with STMEC1; 300 were children's (< 16 years) ears, and 760 were adult's ears. The total observation time was of 12,049 years. The overall estimated proportion with recurrence 5 years after surgery was of 37% in children and of 15% in adults. The older the child was at the first surgery, the risk decreased by 7% per year. In children, canal wall up (CWU) mastoidectomy without obliteration was associated with a hazard ratio for recurrence of 1.9 (95% confidence interval [95%CI]: 1.2–3.0) compared with CWU with obliteration. Conclusion Compared with adults, children were had 2.6 times more risk of recurrence. Procedures performed without mastoidectomy had the lowest risk of recurrence. In children, obliteration was associated with a significantly lower risk of recurrence. However, patients were not randomized regarding the surgical approach; thus, the association between approach and risk of recurrence was likely influenced by confounding factors.

The epidemiology of bacille Calmette-Guérin infections after bladder instillation from 2002 through 2017: a nationwide retrospective cohort study.

To describe incidence and clinical characteristics of bacille Calmette-Guérin (BCG) infections after BCG bladder instillation amongst patients with non-muscle-invasive bladder cancer in Denmark. We conducted a nationwide register-based cohort study in Denmark between 2002 through 2017. Patients with BCG infection were identified by cross-linking data from the Danish National Hospital Registry on patients treated with BCG instillations and patients diagnosed with tuberculosis according to the International Classification of Diseases 10, and data obtained from International Reference Laboratory of Mycobacteriology. Hospital records were reviewed for clinical information. During the study period, 6753 patients (5281 men; mean [SD] age 71.1(0.1)years) received BCG instillations, of which 66 patients (1%) developed BCG infections. There were no differences in age or Charlson Comorbidity Index between the patients in the study population stratified by BCG infection. The median (interquartile range) time from first BCG instillation until symptoms of BCG infection was 169.5(38-585)days. Extrapulmonary localisation of BCG infections (37 patients, 56.1%) was significantly more frequent than pulmonary BCG infections (20 patients, 30.3%; P<0.001). The most common extrapulmonary localisation was the genitourinary tract (29 patients, 78.4%). BCG infections after bladder instillation are rare, mainly affect male patients, and are most frequently extrapulmonary. BCG infections should be suspected despite a long time span between occurrence of symptoms and prior bladder instillation.

M36 - SLEEP DISORDERS AND RISK OF INCIDENT DEPRESSION: A POPULATION CASE-CONTROL STUDY

Background A number of studies have found that disturbed sleep can precede onset of a psychiatric disorder, and that there is substantial comorbidity between sleep disorders and psychiatric disorders, particularly major depression. However, some studies have not been able to establish the temporal relationship between sleep disorders and psychiatric disorders, have been performed in clinical samples, relied on self-report information or have conditioned on the outcome. We sought to investigate and estimate the risk of developing new-onset depression in those with sleep disorders in the entire population of Denmark. Methods Data were obtained by linking longitudinal Danish population-based registers. Information on sleep disorders and major depression was obtained from the Danish National Hospital Register and the Danish Psychiatric Central Research Register. The registers contain records of all hospital visits with a diagnosis given by ICD-10 codes. To account for variability in depression and sleep disorder risk over time, we used a nested case-control design. A total of 65,739 individuals who had first onset of depression between 1995 and 2013 were selected as cases. For each case, a set of 20 controls of the same sex, birth month and year and who had not had depression by the date that the case was diagnosed were selected at random form the population (n=1,307,580 in total). We examined whether there was an increased rate of prior sleep disorders in MDD cases compared to controls using conditional logistic regression. Results We found that there was an increased risk of incident depression in cases for all sleep disorders analysed. Highest incidence rate ratios were found for circadian rhythm disorders (IRR=7.06 (2.78–17.91)) and insomnia of inorganic origin (6.76 (4.37–10.46)). The lowest estimated IRR was for narcolepsy (IRR=2.00 (1.26–3.17)). We also estimated the incidence rate ratio based on time since a sleep disorder diagnosis. Those diagnosed with a sleep disorder in the last 6 months were at highest risk of developing depression compared to those with at least 1 year since diagnosis (3.10 vs 2.36). Discussion Using data from Danish population registers, we show that all categories of sleep disorder are risk factors for incident major depressive disorder. Insomnia and circadian rhythm disorders have the highest associated risk, while narcolepsy and sleep-disordered breathing disorders excluding obstructive sleep apnea have the lowest associated risk. We found differences in risk between men and women for insomnia, obstructive sleep apnea and sleep movement disorders. Furthermore, we found that there is a moderate decrease in risk of depression as the time since diagnosis of a sleep disorder decreases, but that most cases of depression were diagnosed more than a year after diagnosis of a sleep problem. Our results have implications for clinical practice. Depression screening should be considered for patients with sleep disorders, and where possible, long-term follow up for mental health problems is advisable. Differences in risks between genders should also be considered in clinical practice.

Infections and risk of epilepsy in children and young adults: A nationwide study.

The development of epilepsy has been linked to infections of the central nervous system, but recently also to infections and inflammation outside of the central nervous system. Thus we investigated the association between infections and the risk of subsequent epilepsy. This was a Danish nationwide population-based cohort study comprising a total of 1 938 555 individuals born between 1982 and 2012. Individuals were followed from birth until December 31, 2012, death, disappearance, emigration, or epilepsy diagnosis, whichever came first (28 512 666 person-years of follow-up). The exposure was hospital contacts for infection and the outcome was a diagnosis of epilepsy as recorded in the Danish National Hospital Register. Hazard ratios were calculated using Cox proportional hazards models adjusted for age, sex, calendar period, Apgar score, gestational age, birth weight, and parental history of epilepsy. A total of 25 825 individuals received an epilepsy diagnosis during the study period, among whom 8235 (32%) had a previous hospital contact for infection. A hospital contact for infection was associated with a 78% increase in the risk of subsequently receiving an epilepsy diagnosis (hazard ratio 1.78, 95% confidence interval [CI] 1.73-1.83) compared with those without infection. The highest risk was observed after central nervous system infections (hazard ratio 4.97, 95% CI 4.42-5.59), but increased risks were identified across all infected organ systems and types of pathogens. The risk of receiving an epilepsy diagnosis was correlated with the temporal proximity of the infection (P < 0.001) and increased with the number of hospital contacts for infection (P < 0.001) and with the severity of infection (P < 0.001). The risk of receiving an epilepsy diagnosis was increased after a wide range of infections, suggesting that systemic inflammatory processes may be involved in the development of epilepsy.

Guillain-Barré syndrome in Denmark: a population-based study on epidemiology, diagnosis and clinical severity.

To describe the epidemiology and clinical heterogeneity of Guillain-Barré syndrome (GBS) in Denmark and to compare a population-based cohort to prospectively included patients in the International GBS Outcome Study (IGOS). The incidence rate (IR) of GBS in Denmark from September 2012 to December 2015, applying the National Institute of Neurological Disorders and Stroke (NINDS) diagnostic criteria, was estimated and the level of diagnostic certainty was described with the Brighton criteria. All cases registered with a diagnosis of GBS or other inflammatory neuropathies in the Danish National Hospital Registry were reviewed for diagnostic criteria and for information on treatment and clinical course. A total of 299 GBS cases were confirmed, corresponding to a crude IR of 1.59 (95% CI 1.42-1.78) per 100,000 per year. The Brighton criteria level 1-3 of diagnostic certainty was met in 279 (93%) of the patients. Thirty-five percent of the patients were mildly affected (GBS disability score < 3) and a correlation between high age and high disability score at nadir was found (Spearman's rank correlation coefficient 0.42, p < 0.0001). The group of 89 (30%) patients who were enrolled in IGOS had higher GBS disability score at nadir, were admitted 5days earlier, reached nadir 4days faster, and a larger proportion received treatment with IVIg (all p < 0.05). The epidemiology and full clinical spectrum of GBS are described in a population-based study. This includes a larger proportion of milder cases that are underrepresented in prospective cohorts such as IGOS.

Incidences and risk factors of severe infections in young adults with schizophrenia: A nationwide register-based cohort study in Denmark

IntroductionPatients with schizophrenia deal with many risk factors that make them more susceptible to infections. However, knowledge about incidence and the nature of infections among people with schizophrenia is scarce.AimsTo investigate the occurrence and risk factors for severe infections in schizophrenia patients.Objectives– to determine incidence rates of infections among young adults with schizophrenia;– to define risk factors for infections.MethodPopulation-based nationwide cohort study with selection of all individuals born in Denmark between 1975–1990 and follow-up period from 1995–2013 was conducted. Data from the Danish Psychiatric Central Register and the Danish National Hospital Registry were used. A Poisson regression was chosen to estimate incidence rate ratios of infections and to explore the associations of different risk factors like sex, age, substance abuse and medical co-morbidity with the rates of infections.Preliminary results922,564 individuals born between 1975–1990 were included in the study. Overall, 3520 women and 5479 men were identified with schizophrenia. In percentages, 36% with schizophrenia had infectious diseases compared to 25% of background population. Some of severe infections like HIV (0.23% vs 0.05%), sepsis (0.72% vs 0.27%), hepatitis (1.4% vs 0.22%) skin infections (12% vs 6.2%)and tuberculosis (0.12% vs 0.06%) were highly increased in persons with schizophrenia, whereas smaller differences were found regarding CNS infections (0.5% vs 0.4%) and gastrointestinal infections (8.7% vs 6.2%).ConclusionsThe preliminary data results suggest, that individuals with schizophrenia have higher prevalence of all types of severe infectious compared to the background population.Disclosure of interestThe authors have not supplied their declaration of competing interest.

Occupational and recreational physical activity and Parkinson’s disease in Denmark

Objectives This study aimed to examine whether occupational and physical activity (PA) at different ages contribute to Parkinson's disease (PD) risk in a large population-based case-control study in Denmark. Methods We identified 1828 PD patients from the Danish National Hospital Register and recruited 1909 gender and year of birth matched controls from the Danish Central Population Register. Occupational and leisure-time PA were determined from a job exposure matrix based on occupational history and self-reported leisure-time information. Results No association was found for occupational PA alone in men, but higher leisure-time PA (≥5 hours/week of strenuous activities) in young adulthood (15-25 years) was associated with a lower PD risk (adjusted odds ratio (OR adj) 0.75, 95% confidence interval (95% CI) 0.62-0.90); men who engaged in high occupational and high leisure-time PA in young adulthood had the lowest PD risk (OR adj0.58, 95% CI 0.41-0.81). Among women, inverse associations were found for occupation PA before age 50 (highest vs lowest, OR adj0.75, 95% CI 0.55-1.06) and strenuous leisure-time PA after age 50 (OR adj0.65, 95% CI 0.87-0.99); no clear pattern was seen for leisure and occupational PA combined. Conclusions We observed gender-specific inverse associations between occupational and leisure-time PA and PD risk; however, we cannot preclude reverse causation especially in older ages since PD has a long prodromal stage that might lead to a reduction of PA years before motor symptom onset and PD diagnosis.

Eye Disorders among Adult People Diagnosed with Infantile Autism in Childhood: A Longitudinal Case Control Study

ABSTRACTPurpose: The objective of this study was to compare the prevalence and types of eye disorders in a clinical sample of 118 adult people diagnosed with infantile autism (IA) during childhood with 336 sex- and age-matched controls from the general population.Methods: All participants were screened through the nationwide Danish National Hospital Register. The average observation time of both groups was 37.2 years, and mean age was 49.6 years, by the end of the observation period.Results: The overall prevalence of any eye disorder was 15.3% (18/118) in cases with IA, compared to 10.1% (34/336) in controls (p = 0.18). Refraction and accommodation disorders were significantly associated with IA: 7.6% (9/118) vs 1.2% (4/336) (p = 0.001). The rate of eye disorder was particularly high (24.5%) in those with a co-occurring profound or severe learning disability (IQ < 50).Conclusions: Refraction and accommodation disorders were more frequently present in Danish adults with IA, particularly when a profound or severe learning disability was co-present. The increased prevalence of eye disorders in participants with a severe or profound learning disability, and the fact that people with IA do not necessarily realize the presence of a vision deficit, necessitates increased ophthalmological attention.

In utero exposure to β-2-adrenergic receptor agonist and attention-deficit/hyperactivity disorder in children

We aimed to examine the association between in utero exposure to β2AA and risk of attention-deficit/hyperactivity disorder (ADHD). We established a cohort of 672,265 children born from 1998 to 2008 in Denmark. Children were categorized as exposed if their mothers had redeemed a prescription of β2AA in pregnancy (from 30days prior to conception until delivery). We identified children diagnosed with ADHD in the Danish National Hospital Register for the first time after his/her third birthday. Log-linear Poisson regression was used to estimate adjusted incidence rate ratio (aIRR) of ADHD. In total, 25,434 children were born to mothers who had redeemed a β2AA prescription in pregnancy. The exposed children had a 1.31-fold increased risk [aIRR=1.30, 95% confidence interval (CI):1.20-1.42] of ADHD compared to unexposed children after adjusting for potential confounders. However, when extending the exposure window to 2years prior to conception until delivery, exposure to maternal use of β2AA only before pregnancy, only during pregnancy, and both before and during pregnancy was associated with elevated risks of ADHD in children, with aIRRs of 1.31 (95% CI 1.22-1.40), 1.38 (95% CI 1.22-1.57), and 1.30 (95% CI 1.16-1.45), respectively. In mothers with a history of asthma, no association was observed between maternal use of β2AA during pregnancy and ADHD in offspring (aIRR=0.92, 95% CI 0.74-1.15). In utero exposure to β2AA was associated with an increased risk of ADHD in children. However, it is more likely that confounding by indication, the underlying disorders or associated pathological conditions, may explain the association.

Associations Between Autoimmune Diseases and Attention-Deficit/Hyperactivity Disorder: A Nationwide Study

Recent studies have suggested that autoimmune diseases and immune activation play a part in the pathogenesis of different neurodevelopmental disorders. This study investigated the association between a personal history and a family history of autoimmune disease and the risk of developing attention-deficit/hyperactivity disorder (ADHD). A cohort was formed of all singletons born in Denmark from 1990 to 2007, resulting in a study population of 983,680 individuals followed from 1995 to 2012. Information on autoimmune diseases was obtained from the Danish National Hospital Register. Individuals with ADHD were identified through the Danish National Hospital Register and the Danish Psychiatric Central Register. In total, 23,645 children were diagnosed with ADHD during the study period. Autoimmune disease in the individual was associated with an increased risk of ADHD by an incidence rate ratio of 1.24 (95% CI 1.10-1.40). The primary analyses associated maternal autoimmune disease with ADHD in the offspring (incidence rate ratio 1.12, 95% CI 1.06-1.19), whereas a paternal history of autoimmune diseases was not significantly associated with ADHD in the offspring. In exploratory analyses, an increased risk of ADHD was observed for children with a family history of thyrotoxicosis, type 1 diabetes, autoimmune hepatitis, psoriasis, and ankylosing spondylitis. A personal history and a maternal history of autoimmune disease were associated with an increased risk of ADHD. The previously reported association between type 1 diabetes and ADHD was confirmed. In addition, specific parental autoimmune diseases were associated with ADHD in offspring.

Comorbidity of schizophrenia and infection: a population-based cohort study.

In this paper, we investigate the hypothesis that there is an overlap between infection and schizophrenia. Infections have been identified as a risk factor for schizophrenia, but the possible overlap between schizophrenia and infections remains unidentified so far. Here, we describe the use of the comorbidity index, a method for objectively integrating associations into a single measure estimating overlap. Data were drawn from three population-based registers, the Civil Registration Register, the Danish Psychiatric Central Research Register, and the Danish National Hospital Register. We selected a cohort of 1,403,183 persons born in Denmark 1977-2002. Our results indicate that persons who have had a hospital contact with an infection (IRR 1.53, CI 1.46-1.61) are more likely to develop schizophrenia than persons who have not had such a contact. Persons who have had a diagnosis with schizophrenia are more likely to have had a hospital contact with an infection (IRR 1.73, 95% CI 1.57-1.91) than persons who have had no schizophrenia diagnosis. A comorbidity index of 1.40 (95% CI 1.34-1.46) was found, indicating an overlap between schizophrenia and infection. Our findings indicate that schizophrenia and infections overlap and that they share risk factors. The comorbidity index showed that the co-occurrence of schizophrenia and infection was 40% higher than if the two disorders had occurred independently. Although the incidence of schizophrenia and infection was associated with each factor, the overlap could not be explained by urbanicity, parental history of psychiatric admission and infection.

Cancer risk in siblings of children with congenital malformations

PurposeCancer and birth defects cluster in families more often than expected by chance, but the reasons are neither well known nor well studied. MethodsFrom singletons born alive in Denmark between 1 January 1977 and 31 December 2007, we identified children who had no congenital malformations but had a full or half sibling with a congenital malformation (CM) diagnosed in the first year of life; this constituted the exposed group, while children whose siblings had no such condition constituted a reference group. We estimated cancer risks for children who had a full sibling or a half sibling with a CM using a Cox proportional hazards regression model. To control for confounding related to change of family structure, we estimated cancer risks for children from core families and children from broken families separately. Children were followed from birth up to 30 years of age (median follow-up 13.6 years). We obtained information on CMs and cancer from the Danish National Hospital Register and the Danish Cancer Registry. ResultsWe identified 991,454 (78%) children from core families with 53,995 children who had a full sibling with a CM and 277,773 (22%) children from broken families with 7200 children who had a full sibling with a CM and 6194 children who had a half sibling with a CM. Children who had a full sibling with a CM from both core and broken families showed, in general, no increased cancer risk compared with children whose siblings had no CM, except in the case of children who had a full sibling with a CM in the nervous system (HR=2.61, 95%CI:1.60–4.27) or in the eye, ear, face, or neck (HR=2.47, 95%CI: 1.46–4.18). Children who had a half sibling with a CM seemed to have a higher cancer risk in early adulthood (HR=1.87, 95%CI: 0.98–3.56). ConclusionsChildren who had a full sibling with a CM had no increased risk of cancer except for those who had a full sibling with a CM in the nervous system or in the eye, ear, face or neck. Children with a half-sibling with a CM tended to have an increased cancer risk in early adulthood, perhaps a result of chance. This study should be replicated using other data sources.

Diseases of the circulatory system among adult people diagnosed with infantile autism as children: A longitudinal case control study

BackgroundResearch dealing with adult people with autism spectrum disorders (ASD) noticeably lags behind studies of children and young individuals with ASD. AimsThe objective of this study was to compare the prevalence and types of diseases of the circulatory system in a clinical sample of 118 adult people diagnosed with infantile autism (IA) as children with 336 sex and age matched controls from the general population. Methods and proceduresAll participants were screened through the nationwide Danish National Hospital Register. The average observation time of both groups was 37.2 years, and mean age at follow-up was 49.6 years. Outcomes and resultsOf the 118 people with IA, 11 (9.3%) were registered with at least one disease of the circulatory system against 54 (16.1%) in the comparison group (p=0.09; OR=0.54; 95% CI 0.3–1.2). Ischemic heart diseases occurred significantly more frequently among people in the comparison group (p=0.02). Conclusions and implicationsIt is argued that diseases of the circulatory system may be underdiagnosed in people with IA because of the difficulties they face with respect to identifying and communicating symptoms of ill health. Bearing in mind that cardiovascular disease is the primary cause of death in most developed countries, it is suggested that to prevent disease and manage health conditions, health monitoring is essential in adult people with IA.

Neonatal hyperbilirubinemia and the risk of febrile seizures and childhood epilepsy

PurposeThe aim of the study was to estimate the association between newborn children treated with phototerapy for hyperbilirubinemia and the subsequent risk of febrile seizures or epilepsy in early childhood. MethodsWe conducted a follow-up study of singleton children (N=70 230) born between February 1998 and May 2003 from the Danish National Birth Cohort (DNBC). Information on exposure to phototherapy for hyperbilirubinemia was obtained from a questionnaire in the DNBC. Information on epilepsy and febrile seizures were obtained from the Danish National Hospital Registry (DNHR). Cox proportional hazard regression model was used to calculate hazard ratios (HRs) with 95% confidence intervals (CI). ResultsNewborns treated with phototherapy for hyperbilirubinemia had a higher risk of developing epilepsy in early childhood (HR: 1.66, 95% CI: 1.23–2.24) but not febrile seizures (HR: 1.04, 95% CI: 0.86–1.27). The increases risk of epilepsy were only present for boys (HR: 1.98, 95% CI: 1.40–2.78) not for girls (HR: 1.14, 95% CI: 0.64–2.02) ConclusionPhototherapy for hyperbilirubinemia in newborns was associated with an increased risk of epilepsy for males in early childhood. No excess risk was seen with febrile seizures.

Seasonal Variation of Escherichia coli, Staphylococcus aureus, and Streptococcus pneumoniae Bacteremia According to Acquisition and Patient Characteristics: A Population-Based Study.

OBJECTIVE Seasonal variation is a characteristic of many infectious diseases, but relatively little is known about determinants thereof. We studied the impact of place of acquisition and patient characteristics on seasonal variation of bacteremia caused by the 3 most common pathogens. DESIGN Seasonal variation analysis. METHODS In 3 Danish health regions (2.3 million total inhabitants), patients with bacteremia were identified from 2000 through 2011 using information from laboratory information systems. Analyses were confined to Escherichia coli, Staphylococcus aureus, and Streptococcus pneumoniae. Additional data were obtained from the Danish National Hospital Registry for the construction of admission histories and calculation of the Charlson comorbidity index (CCI). Bacteremias were categorized as community acquired, healthcare associated (HCA), and hospital acquired. We defined multiple subgroups by combining the following characteristics: species, acquisition, age group, gender, CCI level, and location of infection. Assuming a sinusoidal model, seasonal variation was assessed by the peak-to-trough (PTT) ratio with a 95% confidence interval (CI). RESULTS In total, we included 16,006 E. coli, 6,924 S. aureus, and 4,884 S. pneumoniae bacteremia cases. For E. coli, the seasonal variation was highest for community-acquired cases (PTT ratio, 1.24; 95% CI, 1.17-1.32), was diminished for HCA (PTT ratio, 1.14; 95% CI, 1.04-1.25), and was missing for hospital-acquired cases. No seasonal variation was observed for S. aureus. S. pneumoniae showed high seasonal variation, which did not differ according to acquisition (overall PTT ratio, 3.42; 95% CI, 3.10-3.83). CONCLUSIONS Seasonal variation was mainly related to the species although the place of acquisition was important for E. coli. Infect Control Hosp Epidemiol 2016;37:946-953.

Risk of myocardial infarction, ischemic stroke, and cardiovascular death in patients with atopic dermatitis

Risk of myocardial infarction, ischemic stroke, and cardiovascular death in patients with atopic dermatitis

Skin Cancer Risk in Hematopoietic Stem-Cell Transplant Recipients Compared With Background Population and Renal Transplant Recipients: A Population-Based Cohort Study.

While a high risk of nonmelanoma skin cancer is well recognized in solid-organ transplant recipients, the risk of skin cancer in hematopoietic stem-cell transplant (HSCT) recipients has not been extensively studied. To determine the risk of cutaneous cancer in HSCT recipients and compare it with the risk in renal transplant recipients (RTRs) and individuals who have not received any transplant. A nationwide population-based cohort study from the Danish National Hospital Register including 3302 patients who underwent HSCT (1007 allogeneic, 2295 autologous) from 1999 through 2014, 4789 RTRs from 1976 through 2014, and 10 age- and sex-matched nontransplanted individuals for each of the groups from the background population. Person-years at risk were calculated from the time of study inclusion until first cutaneous cancer. To compare the risk of skin cancer between transplant recipients and background population, we used a stratified proportional hazard regression model for hazard ratio (HR) estimations. By use of the cumulative incidence, we estimated 5- and 10-year risks of skin cancers. All RTR and HSCT recipients were treated and followed up in specialized hospital departments in Denmark (total population 5.7 million). Primary outcomes were time to first appearance of basal cell carcinoma (BCC), squamous cell carcinoma (SCC), or malignant melanoma (MM) and comparative risk estimates of cutaneous cancers in HSCT recipients and RTRs. The hypothesis was tested during data collection. Allogeneic HSCT recipients had an increased risk of BCC, SCC, and MM, with respective HRs of 3.1 (95% CI, 1.9-5.2), 18.3 (95% CI, 4.1-81.8), and 5.5 (95% CI, 1.7-17.7) compared with the background population. Compared with RTRs, allogeneic HSCT recipients had a 3-fold higher risk of MM. The risk of BCC after allogeneic HSCT was seen only in patients conditioned with total-body irradiation (HR, 3.9 [95% CI, 2.6-6.8]). The risk of BCC was similar for allogeneic HSCT recipients and RTRs, while the risk of SCC was highest for RTRs. Autologous HSCT recipients had no increased risk of skin cancer. Allogeneic HSCT recipients have an increased risk of BCC, SCC, and MM. Total-body irradiation was a major determinant for BCC. Our findings indicate the relevance of dermatologic follow-up in HSCT recipients.