Long COVID exhibits clinically distinct phenotypes at 3-6 months post-SARS-CoV-2 infection: results from the P4O2 consortium

BACKGROUND

Four months after SARS-CoV-2 infection, 22%-50% of COVID-19 patients still experience complaints. Long COVID is a heterogeneous disease and finding subtypes could aid in optimising and developing treatment for the individual patient.

METHODS

Data were collected from 95 patients in the P4O2 COVID-19 cohort at 3-6 months after infection. Unsupervised hierarchical clustering was performed on patient characteristics, characteristics from acute SARS-CoV-2 infection, long COVID symptom data, lung function and questionnaires describing the impact and severity of long COVID. To assess robustness, partitioning around medoids was used as alternative clustering.

RESULTS

Three distinct clusters of patients with long COVID were revealed. Cluster 1 (44%) represented predominantly female patients (93%) with pre-existing asthma and suffered from a median of four symptom categories, including fatigue and respiratory and neurological symptoms. They showed a milder SARS-CoV-2 infection. Cluster 2 (38%) consisted of predominantly male patients (83%) with cardiovascular disease (CVD) and suffered from a median of three symptom categories, most commonly respiratory and neurological symptoms. This cluster also showed a significantly lower forced expiratory volume within 1 s and diffusion capacity of the lung for carbon monoxide. Cluster 3 (18%) was predominantly male (88%) with pre-existing CVD and diabetes. This cluster showed the mildest long COVID, and suffered from symptoms in a median of one symptom category.

CONCLUSIONS

Long COVID patients can be clustered into three distinct phenotypes based on their clinical presentation and easily obtainable information. These clusters show distinction in patient characteristics, lung function, long COVID severity and acute SARS-CoV-2 infection severity. This clustering can help in selecting the most beneficial monitoring and/or treatment strategies for patients suffering from long COVID. Follow-up research is needed to reveal the underlying molecular mechanisms implicated in the different phenotypes and determine the efficacy of treatment.

Precision Medicine for More Oxygen (P4O2)-Study Design and First Results of the Long COVID-19 Extension

Introduction: The coronavirus disease 2019 (COVID-19) pandemic has led to the death of almost 7 million people, however, with a cumulative incidence of 0.76 billion, most people survive COVID-19. Several studies indicate that the acute phase of COVID-19 may be followed by persistent symptoms including fatigue, dyspnea, headache, musculoskeletal symptoms, and pulmonary functional-and radiological abnormalities. However, the impact of COVID-19 on long-term health outcomes remains to be elucidated. Aims: The Precision Medicine for more Oxygen (P4O2) consortium COVID-19 extension aims to identify long COVID patients that are at risk for developing chronic lung disease and furthermore, to identify treatable traits and innovative personalized therapeutic strategies for prevention and treatment. This study aims to describe the study design and first results of the P4O2 COVID-19 cohort. Methods: The P4O2 COVID-19 study is a prospective multicenter cohort study that includes nested personalized counseling intervention trial. Patients, aged 40-65 years, were recruited from outpatient post-COVID clinics from five hospitals in The Netherlands. During study visits at 3-6 and 12-18 months post-COVID-19, data from medical records, pulmonary function tests, chest computed tomography scans and biological samples were collected and questionnaires were administered. Furthermore, exposome data was collected at the patient's home and state-of-the-art imaging techniques as well as multi-omics analyses will be performed on collected data. Results: 95 long COVID patients were enrolled between May 2021 and September 2022. The current study showed persistence of clinical symptoms and signs of pulmonary function test/radiological abnormalities in post-COVID patients at 3-6 months post-COVID. The most commonly reported symptoms included respiratory symptoms (78.9%), neurological symptoms (68.4%) and fatigue (67.4%). Female sex and infection with the Delta, compared with the Beta, SARS-CoV-2 variant were significantly associated with more persisting symptom categories. Conclusions: The P4O2 COVID-19 study contributes to our understanding of the long-term health impacts of COVID-19. Furthermore, P4O2 COVID-19 can lead to the identification of different phenotypes of long COVID patients, for example those that are at risk for developing chronic lung disease. Understanding the mechanisms behind the different phenotypes and identifying these patients at an early stage can help to develop and optimize prevention and treatment strategies.

Diagnostic performance of eNose technology in COVID-19 patients after hospitalization

BACKGROUND

Volatile organic compounds (VOCs) produced by human cells reflect metabolic and pathophysiological processes which can be detected with the use of electronic nose (eNose) technology. Analysis of exhaled breath may potentially play an important role in diagnosing COVID-19 and stratification of patients based on pulmonary function or chest CT.

METHODS

Breath profiles of COVID-19 patients were collected with an eNose device (SpiroNose) 3 months after discharge from the Leiden University Medical Centre and matched with breath profiles from healthy individuals for analysis. Principal component analysis was performed with leave-one-out cross validation and visualised with receiver operating characteristics. COVID-19 patients were stratified in subgroups with a normal pulmonary diffusion capacity versus patients with an impaired pulmonary diffusion capacity (DLCOc < 80% of predicted) and in subgroups with a normal chest CT versus patients with COVID-19 related chest CT abnormalities.

RESULTS

The breath profiles of 135 COVID-19 patients were analysed and matched with 174 healthy controls. The SpiroNose differentiated between COVID-19 after hospitalization and healthy controls with an AUC of 0.893 (95-CI, 0.851-0.934). There was no difference in VOCs patterns in subgroups of COVID-19 patients based on diffusion capacity or chest CT.

CONCLUSIONS

COVID-19 patients have a breath profile distinguishable from healthy individuals shortly after hospitalization which can be detected using eNose technology. This may suggest ongoing inflammation or a common repair mechanism. The eNose could not differentiate between subgroups of COVID-19 patients based on pulmonary diffusion capacity or chest CT.

Myocardial function in COVID-19 patients after hospital discharge: a descriptive study comparing the first and second 'wave' patients

In hospitalized COVID-19 patients, myocardial injury and echocardiographic abnormalities have been described. The present study investigates cardiac function in COVID-19 patients 6 weeks post-discharge and evaluates its relation to New York Heart Association (NYHA) class. Furthermore cardiac function post-discharge between the first and second wave COVID-19 patients was compared. We evaluated 146 patients at the outpatient clinic of the Leiden University Medical Centre. NYHA class of II or higher was reported by 53% of patients. Transthoracic echocardiography was used to assess cardiac function. Overall, in 27% of patients reduced left ventricular (LV) ejection fraction was observed and in 29% of patients LV global longitudinal strain was impaired (> - 16%). However no differences were observed in these parameters reflecting LV function between the first and second wave patients. Right ventricular (RV) dysfunction as assessed by tricuspid annular systolic planar excursion (< 17 mm) was present in 14% of patients, this was also not different between the first and second wave patients (15% vs. 12%; p = 0.63); similar results were found for RV fraction area change and RV strain. Reduced LV and RV function were not associated with NYHA class. In COVID-19 patients at 6 weeks post-discharge, mild abnormalities in cardiac function were found. However these were not related to NYHA class and there was no difference in cardiac function between the first and second wave patients. Long term symptoms post-COVID might therefore not be explained by mildly abnormal cardiac function.

COVID-box Experiences of Patients and Health Care Professionals (COVID-box Project): Single-Center, Retrospective, Observational Study

Background

During the COVID-19 pandemic, several home monitoring programs have described the success of reducing hospital admissions, but only a few studies have investigated the experiences of patients and health care professionals.

Objective

The objective of our study was to determine patients’ and health care professionals’ experiences and satisfaction with employing the COVID-box.

Methods

In this single-center, retrospective, observational study, patients and health care professionals were asked to anonymously fill out multiple-choice questionnaires with questions on a 5-point or 10-point Likert scale. The themes addressed by patients were the sense of reassurance and safety, experiences with teleconsultations, their appreciation for staying at home, and the instructions for using the COVID-box. The themes addressed by health care professionals who treated patients with the COVID-box were the characteristics of the COVID-box, the technical support service and general satisfaction, and their expectations and support for this telemonitoring concept. Scores were interpreted as insufficient (≤2 or ≤5, respectively), sufficient (3 or 6-7, respectively), or good (≥4 or ≥8, respectively) on a 5-point or 10-point Likert scale.

Results

A total of 117 patients and 25 health care professionals filled out the questionnaires. The median score was 4 (IQR 4-5) for the sense of safety, the appreciation for staying at home, and experiences with teleconsultations, with good scores from 76.5% (88/115), 86% (56/65), and 83.6% (92/110) of the patients, respectively. Further, 74.4% (87/117) of the patients scored the home monitoring program with a score of ≥8. Health care professionals scored the COVID-box with a minimum median score of 7 (IQR 7-10) on a 10-point scale for all domains (ie, the characteristics of the COVID-box and the technical support service and general satisfaction). For the sense of safety, user-friendliness, and additional value of the COVID-box, the median scores were 8 (IQR 8-10), 8 (IQR 7-9), and 10 (IQR 8-10), respectively, with good scores from 86% (19/22), 75% (15/20), and 96% (24/25) of the health care professionals, respectively. All health care professionals (25/25, 100%) gave a score of ≥8 for supporting this home monitoring concept, with a median score of 10 (IQR 10-10).

Conclusions

The positive experiences and satisfaction of involved users are key factors for the successful implementation of a novel eHealth solution. In our study, patients, as well as health care professionals, were highly satisfied with the use of the home monitoring program—the COVID-box project. Remote home monitoring may be an effective approach in cases of increased demand for hospital care and high pressure on health care systems.

Home monitoring of lung function, symptoms and quality of life after admission with COVID-19 infection: The HOMECOMIN' study

Background and objective

To develop targeted and efficient follow‐up programmes for patients hospitalized with coronavirus disease 2019 (COVID‐19), structured and detailed insights in recovery trajectory are required. We aimed to gain detailed insights in long‐term recovery after COVID‐19 infection, using an online home monitoring programme including home spirometry. Moreover, we evaluated patient experiences with the home monitoring programme.

Methods

In this prospective multicentre study, we included adults hospitalized due to COVID‐19 with radiological abnormalities. For 6 months after discharge, patients collected weekly home spirometry and pulse oximetry measurements, and reported visual analogue scales on cough, dyspnoea and fatigue. Patients completed the fatigue assessment scale (FAS), global rating of change (GRC), EuroQol‐5D‐5L (EQ‐5D‐5L) and online tool for the assessment of burden of COVID‐19 (ABCoV tool). Mixed models were used to analyse the results.

Results

A total of 133 patients were included in this study (70.1% male, mean age 60 years [SD 10.54]). Patients had a mean baseline forced vital capacity of 3.25 L (95% CI: 2.99–3.44 L), which increased linearly in 6 months with 19.1% (Δ0.62 L, p < 0.005). Patients reported substantial fatigue with no improvement over time. Nevertheless, health status improved significantly. After 6 months, patients scored their general well‐being almost similar as before COVID‐19. Overall, patients considered home spirometry useful and not burdensome.

Conclusion

Six months after hospital admission for COVID‐19, patients' lung function and quality of life were still improving, although fatigue persisted. Home monitoring enables detailed follow‐up for patients with COVID‐19 at low burden for patients and for the healthcare system.

Imatinib in patients with severe COVID-19: a randomised, double-blind, placebo-controlled, clinical trial

BACKGROUND

The major complication of COVID-19 is hypoxaemic respiratory failure from capillary leak and alveolar oedema. Experimental and early clinical data suggest that the tyrosine-kinase inhibitor imatinib reverses pulmonary capillary leak.

METHODS

This randomised, double-blind, placebo-controlled, clinical trial was done at 13 academic and non-academic teaching hospitals in the Netherlands. Hospitalised patients (aged ≥18 years) with COVID-19, as confirmed by an RT-PCR test for SARS-CoV-2, requiring supplemental oxygen to maintain a peripheral oxygen saturation of greater than 94% were eligible. Patients were excluded if they had severe pre-existing pulmonary disease, had pre-existing heart failure, had undergone active treatment of a haematological or non-haematological malignancy in the previous 12 months, had cytopenia, or were receiving concomitant treatment with medication known to strongly interact with imatinib. Patients were randomly assigned (1:1) to receive either oral imatinib, given as a loading dose of 800 mg on day 0 followed by 400 mg daily on days 1-9, or placebo. Randomisation was done with a computer-based clinical data management platform with variable block sizes (containing two, four, or six patients), stratified by study site. The primary outcome was time to discontinuation of mechanical ventilation and supplemental oxygen for more than 48 consecutive hours, while being alive during a 28-day period. Secondary outcomes included safety, mortality at 28 days, and the need for invasive mechanical ventilation. All efficacy and safety analyses were done in all randomised patients who had received at least one dose of study medication (modified intention-to-treat population). This study is registered with the EU Clinical Trials Register (EudraCT 2020-001236-10).

FINDINGS

Between March 31, 2020, and Jan 4, 2021, 805 patients were screened, of whom 400 were eligible and randomly assigned to the imatinib group (n=204) or the placebo group (n=196). A total of 385 (96%) patients (median age 64 years [IQR 56-73]) received at least one dose of study medication and were included in the modified intention-to-treat population. Time to discontinuation of ventilation and supplemental oxygen for more than 48 h was not significantly different between the two groups (unadjusted hazard ratio [HR] 0·95 [95% CI 0·76-1·20]). At day 28, 15 (8%) of 197 patients had died in the imatinib group compared with 27 (14%) of 188 patients in the placebo group (unadjusted HR 0·51 [0·27-0·95]). After adjusting for baseline imbalances between the two groups (sex, obesity, diabetes, and cardiovascular disease) the HR for mortality was 0·52 (95% CI 0·26-1·05). The HR for mechanical ventilation in the imatinib group compared with the placebo group was 1·07 (0·63-1·80; p=0·81). The median duration of invasive mechanical ventilation was 7 days (IQR 3-13) in the imatinib group compared with 12 days (6-20) in the placebo group (p=0·0080). 91 (46%) of 197 patients in the imatinib group and 82 (44%) of 188 patients in the placebo group had at least one grade 3 or higher adverse event. The safety evaluation revealed no imatinib-associated adverse events.

INTERPRETATION

The study failed to meet its primary outcome, as imatinib did not reduce the time to discontinuation of ventilation and supplemental oxygen for more than 48 consecutive hours in patients with COVID-19 requiring supplemental oxygen. The observed effects on survival (although attenuated after adjustment for baseline imbalances) and duration of mechanical ventilation suggest that imatinib might confer clinical benefit in hospitalised patients with COVID-19, but further studies are required to validate these findings.

FUNDING

Amsterdam Medical Center Foundation, Nederlandse Organisatie voor Wetenschappelijk Onderzoek/ZonMW, and the European Union Innovative Medicines Initiative 2.

The Post-COVID-19 Functional Status scale: a tool to measure functional status over time after COVID-19

Since the outbreak of the coronavirus disease 2019 (COVID-19) pandemic, most attention has focused on containing transmission of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and addressing the surge of critically ill patients in acute care settings. Indeed, as of 29 April 2020, over 3 million confirmed cases have been accounted for globally [1]. In the coming weeks and months, emphasis will gradually involve also post-acute care of COVID-19 survivors. It is anticipated that COVID-19 may have a major impact on physical, cognitive, mental and social health status, also in patients with mild disease presentation [2]. Previous outbreaks of coronaviruses have been associated with persistent pulmonary function impairment, muscle weakness, pain, fatigue, depression, anxiety, vocational problems, and reduced quality of life to various degrees [3–5].

An ordinal tool is proposed to measure the full spectrum of functional outcomes following COVID-19. This “Post-COVID-19 Functional Status (PCFS) scale” can be used for tracking functional status over time as well as for research purposes.https://bit.ly/3cofGaa

A home monitoring program including real-time wireless home spirometry in idiopathic pulmonary fibrosis: a pilot study on experiences and barriers

In idiopathic pulmonary fibrosis (IPF), home monitoring experiences are limited, not yet real-time available nor implemented in daily care. We evaluated feasibility and potential barriers of a new home monitoring program with real-time wireless home spirometry in IPF. Ten patients with IPF were asked to test this home monitoring program, including daily home spirometry, for four weeks. Measurements of home and hospital spirometry showed good agreement. All patients considered real-time wireless spirometry useful and highly feasible. Both patients and researchers suggested relatively easy solutions for the identified potential barriers regarding real-time home monitoring in IPF.

Optimizing quality of life in patients with idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a devastating, progressive and ultimately fatal lung disease. The combination of poor prognosis, uncertainty of disease course and severe symptom burden heavily impacts patients' and their families' quality of life. Though new antifibrotic drugs have been shown to decrease disease progression, the effect on health-related quality of life (HRQOL) has not been convincingly demonstrated. In a relentless disease such as IPF, striving to optimize HRQOL should complement the endeavour to prolong life. Unfortunately, there is a paucity of interventions improving symptoms and functionality for patients with IPF, and research focusing on symptom improvement, and assessing and optimizing HRQOL, is limited. This review summarizes the most recent insights into measuring and improving quality of life for patients with IPF, and discusses challenges in the management of this devastating disease. Moreover, we postulate a new model for continuous care in IPF - 'the ABCDE of IPF care': Assessing patients' needs; Backing patients by giving information and support; delivering Comfort care by focusing on treating symptoms and taking into account Comorbidities; striving to prolong life by Disease modification; helping and preparing patients and their caregivers for the eventual End-of-life events that are likely to occur.

Bone age assessment by dual-energy X-ray absorptiometry in children: an alternative for X-ray?

OBJECTIVE

The aim of the study was to validate dual-energy X-ray absorptiometry (DXA) as a method to assess bone age in children.

METHODS

Paired dual-energy X-ray absorptiometry (DXA) scans and X-rays of the left hand were performed in 95 children who attended the paediatric endocrinology outpatient clinic of University Hospital Rotterdam, the Netherlands. We compared bone age assessments by DXA scan with those performed by X-ray. Bone age assessment was performed by two blinded observers according to the reference method of Greulich and Pyle. Intra-observer and interobserver reproducibility were investigated using the intraclass correlation coefficient (ICC), and agreement was tested using Bland and Altman plots.

RESULTS

The intra-observer ICCs for both observers were 0.997 and 0.991 for X-ray and 0.993 and 0.987 for DXA assessments. The interobserver ICC was 0.993 and 0.991 for X-ray and DXA assessments, respectively. The mean difference between bone age assessed by X-ray and DXA was 0.11 years. The limits of agreement ranged from -0.82 to 1.05 years, which means that 95% of all differences between the methods were covered by this range.

CONCLUSIONS

Results of bone age assessment by DXA scan are similar to those obtained by X-ray. The DXA method seems to be an alternative for assessing bone age in a paediatric hospital-based population.

Maternal smoking during pregnancy, fetal arterial resistance adaptations and cardiovascular function in childhood

OBJECTIVE

To unravel the mechanisms underlying the previously demonstrated associations between low birthweight and cardiovascular disease in adulthood, we examined whether maternal smoking during pregnancy leads to fetal arterial resistance adaptations, and subsequently to fetal growth retardation and changes in postnatal blood pressure and cardiac development.

DESIGN

Prospective cohort study from early fetal life onwards.

SETTING

Academic hospital.

POPULATION

Analyses were based on 1120 children aged 2 years.

METHODS

Maternal smoking during pregnancy [non-smoking, first trimester smoking, continued smoking (< 5 and ≥ 5 cigarettes/day)] was assessed by questionnaire.

MAIN OUTCOME MEASURES

Third trimester placental and fetal arterial resistance indices and fetal growth were assessed by ultrasound and Doppler measurements. Postnatal blood pressure and cardiac structures (aortic root diameter, left atrial diameter, left ventricular mass) were measured at 2 years of age.

RESULTS

First trimester smoking was not associated with third trimester placental and fetal blood flow adaptations. Continued smoking of ≥ 5 cigarettes/day was associated with an increased resistance in uterine, umbilical and middle cerebral arteries, and with a decreased flow and diameter of the ascending aorta. Among mothers who continued to smoke, the third trimester estimated fetal weights and birthweights were most affected in children with the highest umbilical artery resistance. Fetal arterial resistance indices were also associated with aortic root diameter and left atrial diameter.

CONCLUSIONS

Fetal arterial resistance adaptations may be involved in the pathways leading from maternal smoking during pregnancy to low birthweight and cardiovascular developmental changes in childhood in the offspring.

Glucocorticoid receptor-9beta polymorphism is associated with systolic blood pressure and heart growth during early childhood. The Generation R Study

BACKGROUND

glucocorticoid receptor-9β polymorphism (rs6198) is associated with the susceptibility for cardiovascular disease.

AIM

to examine whether the GR-9 β variant is also associated with blood pressure and heart growth in early childhood.

STUDY DESIGN

this study was embedded in a population-based prospective cohort study from fetal life onwards. Analyses were based on 857 children.

OUTCOME MEASURES

Left cardiac structures (aortic root diameter, left atrial diameter and left ventricular mass), shortening fraction and heart beat were measured postnatally at the ages of 1.5, 6 and 24 months. Blood pressure was measured at 24 months of age.

RESULTS

the distribution of the GR-9β genotype showed 75.1% homozygous reference, 23.5% heterozygous and 1.4% homozygous variant subjects. No differences in cardiovascular outcomes were observed at the ages of 1.5 and 6 months. At the age of 24 months, homozygous variants showed an increased systolic blood pressure of 2.65 mmHg (95% CI: 0.16, 5.14), an increased heart rate of 9.10 beats per minute (95% CI: 1.28, 16.7) and an increased left ventricular mass of 4.99 g (95% CI: 1.33, 8.65) compared to homozygous references. This means an increase of 2.6%, 8.6% and 16%, respectively. GR-9 β polymorphism was significantly associated with left ventricular mass growth during the first 2 years.

CONCLUSION

our findings suggest that genetically determined differences in cortisol exposure affect cardiovascular development in early life.

Preeclampsia and gestational hypertension are associated with childhood blood pressure independently of family adiposity measures: the Avon Longitudinal Study of Parents and Children

BACKGROUND

Offspring of women with hypertensive disorders of pregnancy are at increased risk of cardiovascular complications later in life, but the mechanisms underlying these associations are unclear. Our aim was to examine whether adjusting for birth weight and familial adiposity changed the association of hypertensive disorders of pregnancy with offspring blood pressure.

METHODS AND RESULTS

Using data from 6343 nine-year-old participants in the Avon Longitudinal Study of Parents and Children, we examined the association between hypertensive disorders of pregnancy (preeclampsia and gestational hypertension) and offspring blood pressure. Both preeclampsia and gestational hypertension were associated with systolic and diastolic blood pressures in the 9-year-old offspring; after adjustment for parental and own adiposity and for other potential confounders, the mean difference in systolic blood pressure was 2.05 mm Hg (95 confidence interval, 0.72 to 3.38) and 2.04 mm Hg (95 confidence interval, 1.42 to 2.67) for preeclampsia and gestational hypertension, respectively, compared with those with no hypertensive disorders of pregnancy. Equivalent results for diastolic blood pressure were 1.00 mm Hg (95 confidence interval, -0.01 to 2.10) and 1.07 mm Hg (95 confidence interval, 0.60 to 1.54). The association of preeclampsia with offspring systolic and diastolic blood pressures attenuated toward the null with further adjustment for birth weight and gestational age, whereas these adjustments did not attenuate the association of gestational hypertension with offspring blood pressure.

CONCLUSIONS

The associations of hypertensive disorders of pregnancy with higher offspring blood pressure are not explained by familial adiposity. The mechanisms linking preeclampsia and gestational hypertension with offspring blood pressure may differ, with the former mediated at least in part by the effect of preeclampsia on intrauterine growth restriction.

Breastfeeding is not associated with left cardiac structures and blood pressure during the first two years of life. The Generation R Study

BACKGROUND

Shorter duration of breastfeeding in infancy has been suggested to be associated with an increased risk of cardiovascular disease in adulthood. Early cardiovascular adaptations due to breastfeeding may explain these associations.

AIM

To investigate whether breastfeeding affects left cardiac structures and blood pressure development in early childhood.

STUDY DESIGN

Prospective cohort study from fetal life until the age of two years.

SUBJECTS

Information about the duration and exclusivity of breastfeeding was collected by questionnaires at the ages of 2, 6 and 12 months in 933 children.

OUTCOME MEASURES

Left cardiac structures (left atrial diameter, aortic root diameter and left ventricular mass), fractional shortening and blood pressure at the ages of 1.5, 6 and 24 months.

RESULTS

No differences in cardiac structures, fractional shortening and blood pressure were observed between breastfed and non-breastfed children. Duration and exclusivity of breastfeeding were not consistently associated with any cardiac structure, fractional shortening, or blood pressure until the age of 24 months. Also, there was no association of breastfeeding with cardiac growth between 6 months and 24 months. All analyses were adjusted for child age and sex. Additional adjustment for child anthropometrics, maternal age, anthropometrics, family history, maternal cardiovascular risk factors, pregnancy or delivery complications, parity, socio-economic status, smoking status and alcohol consumption during pregnancy did not materially change the effect estimates.

CONCLUSIONS

Our results do not support the hypothesis that early postnatal cardiovascular adaptations underlie the previously shown associations between breastfeeding and cardiovascular disease in adulthood. Further studies are needed to investigate whether and at what age the associations appear.

Kidney growth curves in healthy children from the third trimester of pregnancy until the age of two years. The Generation R Study

Information about growth of kidney structures in early life is limited. In a population-based prospective cohort study, from foetal life onwards, we constructed reference curves for kidney growth from the third trimester of pregnancy until early childhood, using data from 1,158 healthy children. Kidney size, defined as length, width, depth and volume, was measured in the third trimester of pregnancy and at the postnatal ages of 6 months and 24 months. Analyses were based on more than 2,500 kidney measurements. In the third trimester of pregnancy and at 6 months of age all kidney measurements were larger in boys than in girls. At 24 months of age, these gender differences were only significant for left kidney structures and right kidney length. Both groups showed trends towards smaller left kidney measurements than right kidney measurements at all ages. Gender-specific reference curves based on post-conceptional and postnatal ages were constructed for left and right kidney length, width, depth and volume. We concluded that kidney size is influenced by age and gender. Left kidney size tended to be smaller than right kidney size, except for kidney length. The reference curves can be used for assessing kidney structures by ultrasound in foetal life and early childhood.

Variation in the IGF1 gene and growth in foetal life and infancy. The Generation R Study

OBJECTIVE

The objective of this study was to examine whether variants of the IGF1 gene are associated with growth patterns from foetal life until infancy.

STUDY DESIGN AND MEASUREMENTS

This study was embedded in the Generation R Study, a population-based prospective cohort study of foetal life. Foetal growth (head circumference, abdominal circumference, femur length, estimated foetal weight) was assessed by ultrasound in early, mid- and late pregnancy. Growth in infancy was assessed at birth (weight) and at the ages of 6 weeks, 6 months and 14 months (head circumference, length, weight). The IGF1 promoter region genotype was determined in 738 children.

RESULTS

Eight alleles of the IGF1 promoter region were identified. In total, 43% of the subjects were homozygous for the most common 192-bp allele (wild-type), 45% were heterozygous, and 12% were noncarriers of the 192-bp allele. No differences were found in birthweight between the three groups. However, noncarriers had a lower estimated foetal weight in mid-pregnancy (P = 0.040), followed by an increased growth rate until 6 months (P < 0.005) in comparison to the 192-bp homozygotes. A similar difference in growth rate was found for length (P < 0.001).

CONCLUSIONS

Variants of the IGF1 promoter region are not associated with birthweight. However, noncarriers of the 192-bp allele tend to have a smaller foetal size, followed by an increased growth rate from mid-pregnancy to early infancy. Studies in larger cohorts are necessary to replicate our findings and to examine whether these effects persist throughout childhood.

Maternal anthropometrics in pregnancy are associated with left ventricular mass in infancy. The generation R study

Pregnancy and early life factors may permanently affect left ventricular growth and development in the offspring. The aim of this study was to examine the associations of maternal anthropometrics during pregnancy with left ventricular mass (LVM) in infancy. This study was embedded in the Generation R Study, a population-based prospective cohort study from fetal life onwards. Maternal anthropometrics were obtained in early (gestational age <18 wk), mid- (gestational age 18-25 wk), and late (gestational age >25 wk) pregnancy. Echocardiographic follow-up measurements were performed in 791 infants aged 6 wk and 6 mo. We found no associations of maternal height, weight, or body mass index (BMI) measured in early, mid-, and late pregnancy with longitudinally measured left ventricular mass (LVM) from 6 wk to 6 mo. Maternal weight gain until late pregnancy was associated with an increased growth of LVM from 6 wk to 6 mo [difference 0.46 g per week for the highest tertile of weight gain compared with the lowest tertile (p value <0.05)]. We concluded that maternal weight gain until late pregnancy is associated with larger LVM at the age of 6 mo, suggesting that maternal health status during pregnancy may have permanent consequences for LVM in their children. Further studies are needed to identify the underlying causal mechanisms and the long-term consequences.

Insulin gene variable number of tandem repeats is not associated with weight from fetal life until infancy: the Generation R Study

OBJECTIVE

The aim of this study was to examine whether the insulin gene variable number of tandem repeats (INS VNTR) is associated with growth patterns in fetal life and infancy.

DESIGN AND METHODS

This study was embedded in the Generation R Study, a population-based prospective cohort study from fetal life until young adulthood. Fetal growth was assessed by ultrasounds in early, mid-, and late pregnancy. Anthropometry in infancy was assessed at birth and at the ages of 6 weeks, 6 months, and 14 months. DNA for genotyping of the INS VNTR promoter region was available in 859 children.

RESULTS

The genotype distribution was I/I 50.8%, I/III 40.0%, and III/III 9.2%. III/III individuals had a shorter gestational age (P<0.005 versus I/I) and a lower birth weight (P<0.05 versus I/I). There were no differences in birth weight after adjusting for gestational age. Class III homozygotes had a smaller abdominal circumference/head circumference (HC) ratio (P<0.005 versus I/I) in mid-pregnancy, but not in late pregnancy. Also, III/III subjects had a relative decrease in HC (SDS) from mid-pregnancy to the age of 14 months (P<0.05 versus I/I). No other differences in pre- and postnatal growth characteristics and patterns were found.

CONCLUSIONS

Class III homozygotes were born at an earlier gestational age. No association was found between INS VNTR and birth weight adjusted for gestational age. Our data suggest that the III/III genotype may be associated with asymmetrical growth in mid-pregnancy, but not in late pregnancy.

Fetal kidney volume and its association with growth and blood flow in fetal life: The Generation R Study

An adverse fetal environment may lead to smaller kidneys and subsequent hypertension with renal disease in adult life. The aim of our study was to examine whether maternal characteristics, fetal growth, fetal blood flow redistribution, or inadequate placental perfusion in different periods of fetal life affect kidney volume in late fetal life. We also determined if fetal kidney volume was linked to the amount of amniotic fluid. In a population-based prospective study from early fetal life, fetal growth characteristics and fetal blood flow parameters were assessed by ultrasound and Doppler examinations in 1215 women in mid- and late-pregnancy. Kidney volume was measured in late pregnancy. Maternal height and pre-pregnancy weight were associated with kidney volume. After adjustment for the same characteristics in late pregnancy, fetal growth and blood flow in mid-pregnancy were not associated with kidney volume in late pregnancy. In late pregnancy, however, all fetal growth parameters were positively linked with kidney volume. The largest effect on kidney volume was found for abdominal circumference. Signs of fetal blood flow redistribution and increased placental resistance were associated with decreased kidney volume in late pregnancy. Amniotic fluid volume was positively associated with kidney volume. Our study shows that maternal anthropometrics, fetal growth, fetal blood flow redistribution, and raised placental resistance all correlate with kidney volume.