Adolescents on psychotropic treatment displayed longer corrected QT intervals than unmedicated controls when they rose rapidly from the supine position

AIM

Psychotropic medication can contribute to arrhythmia and identifying individuals at risk is crucial. This Swedish study compared the corrected QT (QTc) intervals of adolescents on psychotropic medication with unmedicated controls, when supine and after rising rapidly.

METHODS

The study was carried out at Östersund County Hospital in March 2022 and February to March 2023. It comprised 16 cases, aged 10-17 years and 28 controls. QTc intervals were measured with electrocardiography and calculated using Bazett's and Fridericia's formulas. Univariate and multiple linear regressions were used to assess differences in QTc intervals between the cases and controls and across sex, age and body mass index.

RESULTS

The mean QTc interval when supine, calculated with Bazett's formula, was longer for the adolescents on psychotropic medication than the controls (p = 0.046). The same was true for the mean QTc interval after rising rapidly from the supine position, calculated with both Bazett's formula (p = 0.009) and Fridericia's formula (p = 0.007). Mean QTc intervals varied by sex and age groups. Psychotropic medication prolonged QTc intervals, particularly in girls.

CONCLUSION

Longer QTc intervals were found in adolescents on psychotropic medication, particularly after rising rapidly from the supine position.

Risk factors for isolated atrial septal defect secundum morbidity

Atrial septal defect secundum is a common type of congenital heart defect and even more common among children born premature. The aim of this study was to assess premature birth as a potential associated risk factors for cardiac morbidity in children with isolated ASD II. In this retrospective national registry-based case-control study all children born in Sweden between 2010 and 2015 with an isolated ASD II diagnosis were included. Association between premature birth and cardiac morbidity in children with isolated ASD II was assessed by different outcomes-models using conditional logistic regression and adjustments were made for confounding factors. Overall, 11% of children with an isolated ASD II received treatment for heart failure. Down syndrome was the only independent risk factors for associated with cardiac morbidity in children with ASD II (OR = 2.25 (95%CI 1.25-4.07). Preterm birth in children was not associated with an increased risk of ASD II cardiac morbidity.

Insulin resistance prior to term age in very low birthweight infants: a prospective study

OBJECTIVE

To explore the glucose-related hormone profile of very low birthweight (VLBW) infants and assess the association between neonatal hyperglycaemia and insulin resistance during the admission period.

DESIGN

A prospective observational study-the Very Low Birth Weight Infants, Glucose and Hormonal Profiles over Time study.

SETTING

A tertiary neonatal intensive care unit and four neonatal units in county hospitals in Sweden.

PATIENTS

48 infants born <1500 g (VLBW) during 2016-2019.

OUTCOME MEASURES

Plasma concentrations of glucose-related hormones and proteins (C-peptide, insulin, ghrelin, glucagon-like peptide 1 (GLP-1), glucagon, leptin, resistin and proinsulin), insulin:C-peptide and proinsulin:insulin ratios, Homoeostatic Model Assessment 2 (HOMA2) and Quantitative Insulin Sensitivity Check (QUICKI) indices, measured on day of life (DOL) 7 and at postmenstrual age 36 weeks.

RESULTS

Lower gestational age was significantly associated with higher glucose, C-peptide, insulin, proinsulin, leptin, ghrelin, resistin and GLP-1 concentrations, increased HOMA2 index, and decreased QUICKI index and proinsulin:insulin ratio. Hyperglycaemic infants had significantly higher glucose, C-peptide, insulin, leptin and proinsulin concentrations, and lower QUICKI index, than normoglycaemic infants. Higher glucose and proinsulin concentrations and insulin:C-peptide ratio, and lower QUICKI index on DOL 7 were significantly associated with longer duration of hyperglycaemia during the admission period.

CONCLUSIONS

VLBW infants seem to have a hormone profile consistent with insulin resistance. Lower gestational age and hyperglycaemia are associated with higher concentrations of insulin resistance markers.

A longitudinal follow-up of continuous laryngoscopy during exercise test scores in athletes irrespective of laryngeal obstruction, respiratory symptoms, and intervention

BACKGROUND

Exercise-induced laryngeal obstruction (EILO) is diagnosed by the continuous laryngoscopy during exercise (CLE) test. Whether or how much CLE test scores vary over time is unknown. This study aimed to compare CLE test scores in athletes over time, irrespective of respiratory symptoms and grade of laryngeal obstruction.

METHODS

Ninety-eight athletes previously screened for EILO were invited for a follow-up CLE test irrespective of CLE scores and respiratory symptoms. Twenty-nine athletes aged 16-27 did a follow-up CLE test 3-23 months after the baseline test. Laryngeal obstruction at the glottic and supraglottic levels was graded by the observer during exercise, at baseline and follow-up, using a visual grade score (0-3 points).

RESULTS

At baseline, 11 (38%) of the 29 athletes had moderate laryngeal obstruction and received advice on breathing technique; among them, 8 (73%) reported exercise-induced dyspnea during the last 12 months. At follow-up, 8 (73%) of the athletes receiving advice on breathing technique had an unchanged supraglottic score. Three (17%) of the 18 athletes with no or mild laryngeal obstruction at baseline had moderate supraglottic obstruction at follow-up, and none of the 3 reported exercise-induced dyspnea.

CONCLUSIONS

In athletes with repeated testing, CLE scores remain mostly stable over 3-24 months even with advice on breathing technique to those with EILO. However, there is some intraindividual variability in CLE scores over time.

TRIAL REGISTRATION

ISRCTN, ISRCTN60543467, 2020/08/23, retrospectively registered, ISRCTN - ISRCTN60543467: Investigating conditions causing breathlessness in athletes.

Outpatient prescription of pulmonary vasodilator therapy to preterm children with bronchopulmonary dysplasia

AIM

The use of pulmonary vasodilator therapy in children born preterm is largely unknown. Our aim was to map prescription patterns in children with bronchopulmonary dysplasia in Sweden.

METHODS

This was a descriptive national registry-based study of children <7 years who had been prescribed a pulmonary vasodilator during 2007-2017, were born preterm and classified as having bronchopulmonary dysplasia. Information on prescriptions, patient characteristics and comorbidities were retrieved from the Swedish Prescribed Drug Register and linked to other national registers.

RESULTS

The study included 74 children, 54 (73%) born at 22-27 weeks' gestation and 20 (27%) at 28-36 weeks. Single therapy was most common, n = 64 (86.5%), and sildenafil was prescribed most frequently, n = 69 (93%). Bosentan, iloprost, macitentan and/or treprostinil were used mainly for combination therapies, n = 10 (13.5%). Patent ductus arteriosus or atrial septal defect were present in 29 (39%) and 25 (34%) children, respectively, and 20 (69%) versus 3 (12%) underwent closure. Cardiac catheterisation was performed in 19 (26%) patients. Median duration of therapy was 4.6 (1.9-6.8, 95% CI) months. Mortality was 9%.

CONCLUSION

Preterm children with bronchopulmonary dysplasia were prescribed pulmonary vasodilators, often without prior catheterisation. Sildenafil was most commonly used. Diagnostic tools, effects, and drug safety need further evaluation.

Vasodilator therapy for pulmonary hypertension in children: a national study of patient characteristics and current treatment strategies

Pulmonary vasodilator therapy is still often an off-label treatment for pulmonary hypertension in children. The aim of this nationwide register-based study was to assess patient characteristics and strategies for pulmonary vasodilator therapy in young Swedish children. Prescription information for all children below seven years of age at treatment initiation, between 2007 and 2017, was retrieved from the National Prescribed Drug Register, and medical information was obtained by linkage to other registers. All patients were categorized according to the WHO classification of pulmonary hypertension. In total, 233 patients had been prescribed pulmonary vasodilators. The treatment was initiated before one year of age in 61% (N = 143). Sildenafil was most common (N = 224 patients), followed by bosentan (N = 29), iloprost (N = 14), macitentan (N = 4), treprostinil (N = 2) and riociguat (N = 2). Over the study period, the prescription rate for sildenafil tripled. Monotherapy was most common, 87% (N = 203), while 13% (N = 20) had combination therapy. Bronchopulmonary dysplasia (N = 82, 35%) and/or congenital heart defects (N = 156, 67%) were the most common associated conditions. Eight percent (N = 18) of the patients had Down syndrome. Cardiac catheterization had been performed in 39% (N = 91). Overall mortality was 13% (N = 30) during the study period. This study provides an unbiased overview of national outpatient use of pulmonary vasodilator therapy in young children. Few cases of idiopathic pulmonary arterial hypertension were found, but a large proportion of pulmonary hypertension associated with congenital heart defects or bronchopulmonary dysplasia. Despite treatment, mortality was high, and additional pediatric studies are needed for a better understanding of underlying pathologies and evidence of treatment effects.

Evidence of support used for drug treatments in pediatric cardiology

BACKGROUND AND AIMS

Clinical support systems are widely used in pediatric care. The aim of this study was to assess the support for drug treatments used at pediatric cardiac wards and intensive care units in Sweden.

METHODS

Drug information, such as type of drug, indication, dose, and route of administration, for all in-hospital pediatric cardiac patients, was included in the study. Treatments were classified as either on-label (based on product information) or off-label. Support for off-label treatment was stratified by the use of clinical support systems (the national database on drugs, local, or other clinical experience guidelines).

RESULTS

In all, 28 patients were included in the study. The total number of drug treatments was 233, encompassing 65 different drugs. Overall, 175 (75%) treatments were off-label. A majority of off-label drug treatments were supported by other sources of information shared by experts. A total of 7% of the drug treatments were used without support.

CONCLUSION

Off-label drug treatment is still common in Swedish pediatric cardiac care. However, the majority of treatments were supported by the experience shared in clinical support systems.

KEY POINTS

Seventy-five percent of all prescriptions in pediatric cardiology care were off-label.A majority of patients received three or more drug treatments off-label.Use of clinical support systems and guidelines was common, but in 7% of all drug treatments, no support was found for the chosen treatment.

Improved infrastructure and support needed for paediatric clinical trials in Sweden

AIM

There is a lack of authorised medicines for paediatric patients and improved drug development is necessary. The aim of this study was to evaluate the need for infrastructure and support for paediatric clinical trials in Sweden.

METHODS

A web-based survey was sent to doctors and nurses involved in the care of neonates, children and adolescents assessing the current situation and future needs for paediatric clinical trials in Sweden. Questions regarding premises, competence, organisation, support for paediatric clinical trials and Good Clinical Practice Training were addressed.

RESULTS

In total, 137 individuals responded to the survey (109 doctors and 28 nurses). Overall, 61% of the respondents had previous experience of paediatric clinical trials. Some respondents had access to trial units, but only 34% had used the trial unit for support. Half of the responders were interested in recurrent paediatric Good Clinical Practice training. Doctors responded that clinical work often had to be prioritised and emphasised the need for research time.

CONCLUSION

This study clearly shows the commitment for clinical trials among doctors and nurses involved in paediatric care in Sweden, but also that administrative, logistic and economic support in a sustainable setting and an expanded national collaboration are needed.

Cost-effectiveness of palivizumab in infants with congenital heart disease: a Swedish perspective

Background

Infants with congenital heart disease (CHD) have an increased risk of morbidity and mortality during a respiratory syncytial virus (RSV) infection. The aim of this study was to estimate the cost-effectiveness of palivizumab as RSV-prophylaxis among infants with CHD, including the effect of delayed heart surgery and asthma.

Methods

A simulation model with data from the literature and health care authorities including costs and utilities was developed to estimate costs and health effects over a lifetime for a cohort of CHD infants receiving palivizumab compared to no RSV-prophylaxis.

Results

The prophylaxis treatment incurred a cost of 3664 EUR per treated infant. However, due to cost-savings from primarily avoiding hospitalizations (5145 EUR/treated infant) and avoiding heart complications due to delayed heart surgery (2082 EUR/treated infant), the RSV-prophylaxis treatment resulted in a total cost-saving of 3833 EUR per treated infant. At the same time, the prophylaxis-treated cohort accumulated more life-years and higher quality of life than the non-prophylaxis cohort.

Conclusion

This study confirms that RSV-prophylaxis in severe CHD infants less than one year of age is cost beneficial. Avoiding delayed heart surgeries is an important benefit of prophylaxis and should be taken into consideration.

QTc interval-dependent body posture in pediatrics

BACKGROUND

Syncope is a common and often benign disorder presenting at the pediatric emergency department. Long-QT syndrome may be presented with syncope, ventricular arrhythmias or sudden death and is vital to exclude as an underlying cause in children presented with syncope. Few studies have assessed QTc in relation to body posture in children. In this study, we assessed the QTc interval while laying down and during active standing in children with known long-QT syndrome compared to healthy controls.

METHODS

Children aged 1-18 years with long-QT syndrome (N = 17) matched to two healthy controls (N = 34) were included in this case-control study. The ECG standing was performed immediately after the ECG in the supine position. The QTc interval and QTc-difference by changing the body position were calculated.

RESULTS

All children with long-QT syndrome were treated with propranolol. QTc was prolonged among long-QT syndrome children while lying down and when standing up, compared to controls. A prolongation of QTc appeared when standing up for both cases and controls. There was no significant difference in QTc increase between the groups. A QTc over 440 ms was observed among four cases lying down and in eight cases while standing, but not in any of the controls. The standing test with a cut-off of 440 ms showed a sensitivity of 47% and a specificity of 100% for case-status in our study.

CONCLUSION

QTc measured on ECG when rapidly rising up is prolonged in both healthy and LQTS children. More importantly, it prolongs more in children with LQTS and increases in pathological levels.

Predictors of the Need for an Atrial Septal Defect Closure at Very Young Age

An asymptomatic Atrial Septal Defect (ASD) is often closed at the age of 3–5 years using a transcatheter or surgical technique. Symptomatic ASD or ASD associated with pulmonary hypertension (PHT) may require earlier closure, particularly in combination with other non-cardiac risk factors for PHT, but the indications for early closure and the potential risk for complications are largely unknown. The aim of this study was to assess risk factors for needing ASD closure during the first and second years of life. This case-control study included all children treated with surgical or percutaneous ASD closure between 2000 and 2014 at two out of three pediatric heart centers in Sweden. “Cases” were children with ASD closure at ≤1 or ≤2 years of age. Clinical data were retrieved from medical journals and national registries. Overall, 413 children were included. Of these, 131 (32%) were ≤2 years, and 50 (12%) were ≤1 year. Risk factors associated with a ≤2 years ASD closure were preterm birth, OR = 2.4 (95% CI: 1.5–3.9); additional chromosomal abnormalities, OR = 3.4 (95% CI: 1.8–6.5); pulmonary hypertension, OR = 5.8 (95% CI: 2.6–12.6); and additional congenital heart defects, OR = 2.6 (95% CI: 1.7–4.1). These risk associations remained after adjustments for confounding factors, such as need for neonatal respiratory support, neonatal pulmonary diseases, neonatal sepsis, additional congenital heart defects (CHD) and chromosomal abnormalities. ASD size:body weight ratio of 2.0, as well as a ratio of 0.8 (upper and lower limit of the ASD size:body weight ratios), was associated with increased risk of an early ASD closure. Risk factors such as very premature birth, very low birth weight, congenital, and chromosomal abnormalities, neonatal pulmonary disease and need for ventilation support, as well as pulmonary hypertension, were associated with very early (<1 year of age) ASD closure. Several independent neonatal risk factors were associated with an increased risk of early ASD closure at 2 and at 1 year of age. An ASD size:body weight ratio is a poor predictor for indications for ASD closure.

Increased risk of pulmonary hypertension following premature birth

Background

Pulmonary hypertension (PAH) among children and adults has been linked to premature birth, even after adjustments for known risk factors such as congenital heart disease and chronic lung disease. The aim of this population-based registry study was to assess the risk of PAH following exposure to premature birth and other factors in the decades when modern neonatal care was introduced and survival rates increased.

Methods

Data on pulmonary hypertension and perinatal factors were retrieved from population-based governmental and national quality registers. Cases were adults and children over five years of age with pulmonary hypertension born from 1973 to 2010 and individually matched to six controls by birth year and delivery hospital. Conditional multiple logistic regression was performed to assess the risk of pulmonary hypertension following premature birth and to adjust for known confounding factors for the total study population and for time of birth, grouped into five-year intervals.

Results

In total, 128 cases and 768 controls were included in the study group. Preterm birth was over three times more common among cases (21%) than among controls (6%). The overall adjusted risk of pulmonary hypertension was associated with premature birth, OR = 4.48 (95% CI; 2.10–9.53). Maternal hypertension, several neonatal risk factors and female gender were independently associated with PAH when potential confounders were taken into account. For each five-year period, the risk of PAH following premature birth increased several times for children born in the 2000s and later, OR = 17.08 (95% CI 5.60–52.14).

Conclusions

Preterm birth, along with other factors, significantly contributes to PAH. PAH following premature birth has increased over the last few decades. Our study indicates that new, yet unknown factors may play a role in the risk of preterm-born infants developing PAH later in life.

Inhaled corticosteroids in children with persistent asthma: effects of different drugs and delivery devices on growth

BACKGROUND

Inhaled corticosteroids (ICS) are the most effective treatment for children with persistent asthma. Although treatment with ICS is generally considered to be safe in children, the potential adverse effects of these drugs on growth remains a matter of concern for parents and physicians.

OBJECTIVES

To assess the impact of different inhaled corticosteroid drugs and delivery devices on the linear growth of children with persistent asthma.

SEARCH METHODS

We searched the Cochrane Airways Trials Register, which is derived from systematic searches of bibliographic databases including CENTRAL, MEDLINE, Embase, CINAHL, AMED and PsycINFO. We handsearched respiratory journals and meeting abstracts. We also conducted a search of ClinicalTrials.gov and manufacturers' clinical trial databases, or contacted the manufacturer, to search for potential relevant unpublished studies. The literature search was initially conducted in September 2014, and updated in November 2015, September 2018, and April 2019.

SELECTION CRITERIA

We selected parallel-group randomized controlled trials of at least three months' duration. To be included, trials had to compare linear growth between different inhaled corticosteroid molecules at equivalent doses, delivered by the same type of device, or between different devices used to deliver the same inhaled corticosteroid molecule at the same dose, in children up to 18 years of age with persistent asthma.

DATA COLLECTION AND ANALYSIS

At least two review authors independently selected studies and assessed risk of bias in included studies. The data were extracted by one author and checked by another. The primary outcome was linear growth velocity. We conducted meta-analyses using Review Manager 5.3 software. We used mean differences (MDs) and 95% confidence intervals (CIs ) as the metrics for treatment effects, and the random-effects model for meta-analyses. We did not perform planned subgroup analyses due to there being too few included trials.

MAIN RESULTS

We included six randomized trials involving 1199 children aged from 4 to 12 years (per-protocol population: 1008), with mild-to-moderate persistent asthma. Two trials were from single hospitals, and the remaining four trials were multicentre studies. The duration of trials varied from six to 20 months.One trial with 23 participants compared fluticasone with beclomethasone, and showed that fluticasone given at an equivalent dose was associated with a significant greater linear growth velocity (MD 0.81 cm/year, 95% CI 0.46 to 1.16, low certainty evidence). Three trials compared fluticasone with budesonide. Fluticasone given at an equivalent dose had a less suppressive effect than budesonide on growth, as measured by change in height over a period from 20 weeks to 12 months (MD 0.97 cm, 95% CI 0.62 to 1.32; 2 trials, 359 participants; moderate certainty evidence). However, we observed no significant difference in linear growth velocity between fluticasone and budesonide at equivalent doses (MD 0.39 cm/year, 95% CI -0.94 to 1.73; 2 trials, 236 participants; very low certainty evidence).Two trials compared inhalation devices. One trial with 212 participants revealed a comparable linear growth velocity between beclomethasone administered via hydrofluoroalkane-metered dose inhaler (HFA-MDI) and beclomethasone administered via chlorofluorocarbon-metered dose inhaler (CFC-MDI) at an equivalent dose (MD -0.44 cm/year, 95% CI -1.00 to 0.12; low certainty evidence). Another trial with 229 participants showed a small but statistically significant greater increase in height over a period of six months in favour of budesonide via Easyhaler, compared to budesonide given at the same dose via Turbuhaler (MD 0.37 cm, 95% CI 0.12 to 0.62; low certainty evidence).

AUTHORS' CONCLUSIONS

This review suggests that the drug molecule and delivery device may impact the effect size of ICS on growth in children with persistent asthma. Fluticasone at an equivalent dose seems to inhibit growth less than beclomethasone and budesonide. Easyhaler is likely to have less adverse effect on growth than Turbuhaler when used for delivery of budesonide. However, the evidence from this systematic review of head-to-head trials is not certain enough to inform the selection of inhaled corticosteroid or inhalation device for the treatment of children with persistent asthma. Further studies are needed, and pragmatic trials and real-life observational studies seem more attractive and feasible.

National cohort study showed that infants with Down's syndrome faced a high risk of hospitalisation for the respiratory syncytial virus

AIM

The respiratory syncytial virus (RSV) is a leading cause of hospitalisation in infants. We investigated this risk in children with Down's syndrome under two years of age, adjusted for other known risk factors.

METHODS

This national, retrospective 1:2 matched cohort study comprised all Swedish children born with Down's from 2006 to 2011, who were each randomly matched to two controls without Down's. Data on RSV hospitalisation and risk factors for RSV were obtained from national registers. The risk of RSV hospitalisation was assessed using multivariable Cox regression with pairwise stratification.

RESULTS

The study comprised 814 children with Down's and 1628 controls. We found that 82 children with Down's (10.1%) and 22 controls (1.4%) were hospitalised for RSV. The hazard ratio for children with Down's was 4.00 (95% confidence interval 1.58-10.13) for up to one year of age and 6.60 (95% CI: 2.83-15.38) for up to two years of age, adjusted for other risk factors. During the second year of life, RSV hospitalisation continued for children with Down's, while it was minimal for the controls.

CONCLUSION

Children with Down's faced a high risk of RSV hospitalisation, which continued beyond the first year of age.

Risk factors for pulmonary arterial hypertension in children and young adults

OBJECTIVES

Pulmonary hypertension (PH) has been linked to preterm birth explained by congenital heart defects and pulmonary diseases.

WORKING HYPOTHESIS

Other factors may influence the risk of PH among adolescences and children born premature.

STUDY DESIGN

This national registry-based study assess risk of PH following premature birth adjusted for known risk factors.

PATIENT-SUBJECT SELECTION AND METHODOLOGY

All cases born 1993-2010, identified by diagnostic codes applicable to PH and retrieved from the Swedish Registry of Congenital Heart Disease (N = 67). Six controls were randomly selected and matched to each case by year of birth and hospital by the Swedish Medical Birth Register (N = 402). Maternal and infant data related to preterm birth, pulmonary diseases, and congenital defects were retrieved. The association between preterm birth and pulmonary hypertension was calculated by conditional logistic regression taking into account potential confounding factors.

RESULTS

One third of the cases and seven percent of the controls were born preterm in our study. Preterm birth was associated with PH, OR = 8.46 (95%CI 2.97-24.10) (P < 0.0001) even after adjusting for confounding factors. Other factors, such as acute pulmonary diseases, congenital heart defects, congenital diaphragm herniation, and chromosomal disorders were also associated with PH in the multivariate analysis.

CONCLUSIONS

Children and young adults born preterm are known to have an increased risk of PH, previously explained by congenital heart defects and pulmonary diseases. By adjusting for such factors, our study indicates that new factors may play a role in the risk of developing PH among children born preterm. Pediatr Pulmonol. 2017;52:636-641. © 2016 Wiley Periodicals, Inc.

B12 deficiency is common in infants and is accompanied by serious neurological symptoms

AIM

Adverse neurological symptoms have been linked to vitamin B12 deficiency in infants. This explorative study described the clinical presentation associated with vitamin B12 deficiency in this age group.

METHODS

The study comprised infants who were born between 2004 and 2012 and were tested for vitamin B12 levels after they were admitted to a hospital with neurological symptoms at less than one year of age. Vitamin B12 deficiency was defined as low cobalamin in serum and/or increased homocysteine and/or increased methylmalonate. It was diagnosed according to the applicable International Classification of Diseases, 10th revision, and recorded as vitamin B12 deficiency in the medical records. All information was retrieved from medical records and compared to symptomatic infants with normal levels.

RESULTS

Of the 121 infants tested, 35 had vitamin B12 deficiency and 86 had normal levels. Vitamin B12 deficiency was diagnosed at an average age of 1.7 months and was more common among boys. Seizures and apparent life-threatening events were the most common symptoms among infants with B12 deficiency compared to infants with normal levels.

CONCLUSION

Vitamin B12 deficiency was more common in infants than we expected and presented with severe symptoms, such as seizures and apparent life-threatening events.

Serious complications in male infant circumcisions in Scandinavia indicate that this always be performed as a hospital-based procedure

AIM

More than 7000 male circumcisions are performed in Scandinavia every year. Circumcision is regulated in different ways in Sweden and Denmark and Norway. This study reviewed and described factors associated with complications of circumcision in infant boys in Scandinavia over the last two decades and discussed how these complications could be avoided.

METHODS

Data on significant complications following circumcision on boys under the age of one in Scandinavia over the last 20 years were collected. Information was retrieved from testimonies of circumcisers, witnesses, medical records and verdicts. A systematic review was performed of fatal cases in the literature.

RESULTS

We found that 32 cases had been reported to the health authorities in the three countries, and we identified a total of 74 complications in these cases. These included four boys with severe bleeding and circulatory shock, which ended in the death of one boy. Other less serious complications may have occurred in other boys, but not been reported.

CONCLUSION

Complications following male circumcision in Scandinavia were relatively rare, but serious complications did occur. Based on the analyses of the severe cases, we argue that circumcision should only be performed at hospitals with 24-hour emergency departments.

Respiratory Tract Infection and Risk of Hospitalization in Children with Congenital Heart Defects During Season and Off-Season: A Swedish National Study

Respiratory tract infections (RTI) are common among young children, and congenital heart defect (CHD) is a risk factor for severe illness and hospitalization. This study aims to assess the relative risk of hospitalization due to RTI in winter and summer seasons for different types of CHD. All children born in Sweden and under the age of two, in 2006-2011, were included. Heart defects were grouped according to type. Hospitalization rates for respiratory syncytial virus (RSV) infection and RTI in general were retrieved from the national inpatient registry. The relative risk of hospitalization was calculated by comparing each subgroup to other types of CHD and otherwise healthy children. The relative risk of hospitalization was increased for all CHD subgroups, and there was a greater increase in risk in summer for the most severe CHD. This included RSV infection, as well as RTI in general. The risk of hospitalization due to RTI is greater for CHD children. Prophylactic treatment with palivizumab, given to prevent severe RSV illness, is only recommended during winter. We argue that information to healthcare staff and parents should include how the risk of severe infectious respiratory tract illnesses, RSV and others, is present all year round for children with CHD.

Some neonatal risk factors for adult pulmonary arterial hypertension remain unknown

AIM

Pulmonary hypertension has been linked to premature birth, chronic lung disease, bronchopulmonary dysplasia and congenital heart disease. This national population-based registry study assessed the risk of adult pulmonary hypertension following premature birth, adjusted for known risk factors.

METHODS

We focused on adults in the Swedish Pulmonary Arterial Hypertension Registry, who were born prematurely, and controls randomly selected from the Swedish medical birth register and matched to each case by birth year and delivery hospital. Information on perinatal factors was also retrieved from the medical birth register. Conditional multiple logistic regression was used to evaluate the association between premature birth and adult pulmonary hypertension, taking into account the potential confounding factors.

RESULTS

The study population comprised 427 adults born between 1973 and 1996, with 61 cases and 366 controls. Adult pulmonary hypertension was associated with premature birth, with an odds ratio of 3.08 and 95% confidence interval of 1.21-7.87. The association did not alter after adjusting for potential confounders.

CONCLUSION

By adjusting for factors linked to adult pulmonary hypertension, namely congenital heart defects, pulmonary diseases and premature birth, we were able to show that other unknown factors may influence the risk for pulmonary hypertension among adults who were born premature.

Evaluating national guidelines for the prophylactic treatment of respiratory syncytial virus in children with congenital heart disease

AIM

This is the first study to evaluate compliance with the 2003 Swedish national guidelines for prophylactic treatment of respiratory syncytial virus (RSV) in children with congenital heart disease (CHD). We estimated the relative risk (RR) of children with CHD being hospitalised with a RSV infection, studied the extent to which RSV prophylactic treatment with palivizumab corresponded to the guidelines and determined the morbidity of children with CHD who developed RSV infection despite prophylaxis.

METHODS

This national observational study comprised prospectively registered data on 219 children with CHD treated with palivizumab, medical records on RSV cases and information on hospitalisation rates of children with CHD and RSV infection.

RESULTS

The calculated RR of children with CHD being hospitalised with RSV infection was 2.06 (95% CI 1.6-2.6; p < 0.0001) compared with children without CHD. Approximately half of the patients (49%) born before the RSV season and 25% born during the RSV season did not start treatment as recommended by the guidelines.

CONCLUSION

Having CHD increased the rate and estimated RR of children being hospitalised with RSV infection. The guidelines were not followed for about half of the children born before a RSV season and a quarter of the children born during a RSV season and need updating.

Enhanced monsoon precipitation and nitrogen deposition affect leaf traits and photosynthesis differently in spring and summer in the desert shrub Larrea tridentata

Leaf-level CO2 assimilation (A(area)) can largely be predicted from stomatal conductance (g(s)), leaf morphology (SLA) and nitrogen (N) content (N(area)) in species across biomes and functional groups. The effects of simulated global change scenarios, increased summer monsoon rain (+H2O), N deposition (+N) and the combination (+H2O +N), were hypothesized to affect leaf trait-photosynthesis relationships differently in the short- and long-term for the desert shrub Larrea tridentata. During the spring, +H2O and +H2O +N plants had lower A(area) and g(s), but similar shoot water potential (Psi(shoot)) compared with control and +N plants; differences in A(area) were attributed to lower leaf N(area) and g(s). During the summer, +H2O and +H2O +N plants displayed higher A(area) than control and +N plants, which was attributed to higher Psi(shoot), g(s) and SLA. Throughout the year, A(area) was strongly correlated with g(s) but weakly correlated with leaf N(area) and SLA. We concluded that increased summer monsoon had a stronger effect on the performance of Larrea than increased N deposition. In the short term, the +H2O and +H2O +N treatments were associated with increasing A(area) in summer, but also with low leaf N(area) and lower A(area) in the long term the following spring.

Supplementary oxygen and risk of childhood lymphatic leukaemia

AIM

Childhood leukaemia has been linked to several factors, such as asphyxia and birthweight, which in turn are related to newborn resuscitation. Based on the findings from a previous study a population-based case-control study was performed to investigate the association between childhood leukaemia and exposure to supplementary oxygen and other birth-related factors.

METHODS

Children born in Sweden and diagnosed with lymphatic leukaemia between 1973 and 1989 (578 cases) were individually matched by gender and date of birth to a randomly selected control. Children with Down's syndrome were excluded. Exposure data were blindly gathered from antenatal, obstetric and other standardized medical records. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated by conditional logistic regression.

RESULTS

Resuscitation with 100% oxygen with a facemask and bag immediately postpartum was significantly associated with an increased risk of childhood lymphatic leukaemia (OR = 2.57, 95% Cl 1.21-6.82). The oxygen-related risk further increased if the manual ventilation lasted for 3 min or more (OR = 3.54, 95% CI 1.16-10.80). Low Apgar scores at 1 and 5 min were associated with a non-significantly increased risk of lymphatic leukaemia. There were no associations between lymphatic leukaemia and supplementary oxygen later in the neonatal period or other birth-related factors.

CONCLUSION

Resuscitation with 100% oxygen immediately postpartum is associated with childhood lymphatic leukaemia, but further studies are warranted to confirm the findings.

[Results of recent research on perinatal risk factors: resuscitation using oxygen increases the risk of childhood leukemia]

The five studies presented in this thesis were all conducted in Sweden as population based case-control studies. Children with Down's syndrome were excluded. A total of 652 cases were encompassed in the studies. Exposure data were blindly extracted from standardized medical records. There was no association between prenatal exposure to ultrasound or diagnostic x-rays and childhood leukemia. A history of maternal lower genital tract infection significantly increased the risk of childhood leukemia. This association was especially evident in children diagnosed at four years or older or in infancy. Resuscitation with 100% oxygen with a facemask and bag directly postpartum was associated with increased risk of childhood lymphatic leukemia. Previously described exposure risks related to childhood leukemia could not be confirmed by these studies. However, this thesis indicates that events during pregnancy or the neonatal period are associated with increased risks of lymphatic and infant leukemia.

Perinatal exposure to infection and risk of childhood leukemia

BACKGROUND

A population-based case-control study was conducted to investigate the association between childhood leukemia and infectious exposures during pregnancy and early neonatal period.

PROCEDURE

Children born and diagnosed with leukemia between 1973 and 1989 in Sweden (578 lymphatic, 74 myeloid) were selected as cases. One control was randomly selected for each case and individually matched by sex, month, and year of birth. Children with Down's syndrome were excluded. Exposure data were blindly abstracted from antenatal, obstetric, and other standardized medical records. Odds ratios (OR) and 95% confidence intervals (CI) were calculated by conditional logistic regression.

RESULTS

A history of maternal infection was not significantly associated with childhood leukemia, OR = 1.25 (95% CI 0.95-1.65). Maternal lower genital tract infection significantly increased the risk of childhood leukemia, OR = 1.78 (95% CI 1.17-2.72), and especially for children over 4 years of age at diagnosis, OR = 2.01 (95% CI 1.12-3.80). Neonatal infection was not associated with the risk of leukemia. The results remained unaltered after adjustment for potential confounders, and separate analyses for myeloid and lymphoid leukemia.

CONCLUSIONS

We could document an association between exposure to maternal lower genital tract infection in utero, and a subsequent risk for childhood leukemia, which indicate the importance of an early exposure.

Childhood leukemia and magnetic fields in infant incubators

In studies of magnetic field exposure and childhood leukemia, power lines and other electrical installations close to the children's homes constitute the most extensively studied source of exposure. We conducted a study to assess whether exposure to magnetic fields in infant incubators is associated with an increased leukemia risk. We identified all children with leukemia born in Sweden between 1973 and 1989 from the national Cancer Registry and selected at random one control per case, individually matched by sex and time of birth, from the study base. We retrieved information about treatment in infant incubators from medical records. We made measurements of the magnetic fields inside the incubators for each incubator model kept by the hospitals. Exposure assessment was based on measurements of the magnetic field level inside the incubator, as well as on the length of treatment. For acute lymphoblastic leukemia, the risk estimates were close to unity for all exposure definitions. For acute myeloid leukemia, we found a slightly elevated risk, but with wide confidence intervals and with no indication of dose response. Overall, our results give little evidence that exposure to magnetic fields inside infant incubators is associated with an increased risk of childhood leukemia.

Intrauterine exposure to diagnostic X rays and risk of childhood leukemia subtypes

The relationship between childhood leukemia and prenatal exposure to low-dose ionizing radiation remains debatable. This population-based case-control study investigated the association between prenatal exposure to diagnostic X-ray examinations (for different types of examinations and at different stages of pregnancy) and the risk of childhood lymphatic and myeloid leukemia. All children born and diagnosed with leukemia between 1973-1989 in Sweden (578 lymphatic and 74 myeloid) were selected as cases, and each was matched (by sex and year of birth) to a healthy control child (excluding Down's syndrome). Exposure data were abstracted blindly from all available medical records. Odds ratios (OR) and 95% confidence intervals (CI) were calculated by conditional logistic regression. It was found that prenatal X-ray examinations resulting in direct fetal exposure were not associated with a significant overall increased risk for childhood leukemia (OR = 1.11, 95% CI 0.83-1.47), for lymphatic leukemia (OR = 1.04, 95% CI 0.77-1.40), or for myeloid leukemia (OR = 1.49, 95% CI 0.48-4.72). There was little evidence of a dose response or variation in risk by trimester of exposure or age at diagnosis. Thus X-ray examinations performed during pregnancy in the 1970s and 1980s in Sweden did not affect the risk of childhood leukemia discernibly.

Fetal tachycardia: intrauterine and postnatal course

Eighteen consecutive cases of fetal tachycardia referred to the department of Pediatric Cardiology, Uppsala University, were studied retrospectively. All cases were detected at a routine visit at an antenatal clinic. None of the cases had a structural heart disease. Fetal supraventricular tachycardia was found in 8 cases and atrial flutter in 10 cases. In 7 cases, hydrops and heart failure were diagnosed. Antenatal treatment with digoxin, alone or in combination with other antiarrhythmic drugs, was needed in 15 cases. In 10 cases an obvious effect of the therapy was observed. No intrauterine deaths occurred. One infant died postnatally. At birth, 4 infants were in need of neonatal intensive care when delivered. Antiarrhythmic treatment was started in 13 cases postnatally. Late relapse of tachycardia was reported in 3 children. In 1 of these cases the prenatal tachycardia had resolved spontaneously and the infant was not treated antenatally nor during the neonatal period. Although fetal tachycardia is a serious condition, antenatal treatment in combination with careful monitoring and induction of delivery in cases with deteriorating fetal condition result in a satisfactory outcome for the majority of infants. However, there is a risk of late recurrence.

Voices from family medicine: toward the 21st century. Interview by William B. Ventres and John J. Frey

Throughout STFM's 25th anniversary year, we illustrated the dynamic history of family medicine using the personal narratives of some of the discipline's founders and early leaders. We have attempted to take the energy of their spoken words and put it on paper for clinician educators to learn from and lead by. For us, as authors, this process has been enriching and has caused us to reexamine and confirm the meanings of our roles as teachers in family medicine. In this final installment, we present five new voices: individuals from succeeding generations of academic family physicians. Like the many others we interviewed but have not included here, these five individuals were identified by colleagues for their demonstrated leadership in the discipline. They and others will help mold the future of family medicine well into the 21st century.

Sudden infant death and home monitors

During a two-year period, ten infants died suddenly and unexpectedly with a home cardiorespiratory monitor available. We investigated the compliance with appropriate monitoring technique as well as the medical and demographic factors associated with these deaths (90% were due to sudden infant death syndrome). At least six and probably eight of these ten families were noncompliant with appropriate monitoring technique. The main comparison group consisted of 211 patients for whom care with home cardiorespiratory monitors was initiated and continued. Bronchopulmonary dysplasia and severe, apparent life-threatening events were significantly increased in the subjects, as were the following characteristics: black race; lack of private medical insurance; unmarried mother; maternal age of less than 25 years; cigarette smoking by mother during pregnancy; and low Apgar scores. These diagnostic and demographic factors may be useful in predicting the infant at highest risk for sudden and unexpected death when a home monitor is prescribed. Noncompliance with proper monitoring technique patients; methods of educating parents of infants at high risk of sudden infant death syndrome with the necessity for compliance need to be developed.