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.

Fibrotic-like abnormalities notably prevalent one year after hospitalization with COVID-19.

BACKGROUND: We investigated whether COVID-19 leads to persistent impaired pulmonary function, fibrotic-like abnormalities or psychological symptoms 12 months after discharge and whether severely ill patients (ICU admission) recover differently than moderately ill patients. METHODS: This single-centre cohort study followed adult COVID-19 survivors for a period of one year after discharge. Patients underwent pulmonary function tests 6 weeks, 3 months and 12 months after discharge and were psychologically evaluated at 6 weeks and 12 months. Computed tomography (CT) was performed after 3 months and 12 months. RESULTS: 66 patients were analysed, their median age was 60.5 (IQR: 54-69) years, 46 (70%) patients were male. 38 (58%) patients had moderate disease and 28 (42%) patients had severe disease. Most patients had spirometric values within normal range after 12 months of follow-up. 12 (23%) patients still had an impaired lung diffusion after 12 months. Impaired pulmonary diffusion capacity was associated with residual CT abnormalities (OR 5.1,CI-95: 1.2-22.2), shortness of breath (OR 7.0, CI-95: 1.6-29.7) and with functional limitations (OR 5.8, CI-95: 1.4-23.8). Ground-glass opacities resolved in most patients during follow-up. Resorption of reticulation, bronchiectasis and curvilinear bands was rare and independent of disease severity. 81% of severely ill patients and 37% of moderately ill patients showed residual abnormalities after 12 months (OR 8.1, CI-95: 2.5-26.4). A minority of patients had symptoms of post-traumatic stress disorder, anxiety, depression and cognitive failure during follow-up. CONCLUSION: Some patients still had impaired lung diffusion 12 months after discharge and fibrotic-like residual abnormalities were notably prevalent, especially in severely ill patients.

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.

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.

Maternal smoking during pregnancy and kidney volume in the offspring: the Generation R Study.

An adverse fetal environment leads to smaller kidneys, with fewer nephrons, which might predispose an individual to the development of kidney disease and hypertension in adult life. In a prospective cohort study among 1,072 children followed from early fetal life onward, we examined whether maternal smoking during pregnancy, as a significant adverse fetal exposure, is associated with fetal (third trimester of pregnancy, n = 1,031) and infant kidney volume (2 years of age, n = 538) measured by ultrasound. Analyses were adjusted for various potential confounders. Among mothers who continued smoking, we observed dose-dependent associations between the number of cigarettes smoked during pregnancy and kidney volume in fetal life. Smoking less than five cigarettes per day was associated with larger fetal combined kidney volume, while smoking more than ten cigarettes per day tended to be associated with smaller fetal combined kidney volume (p for trend: 0.002). This pattern was not significant for kidney volume at the age of 2 years. Our results suggest that smoking during pregnancy might affect kidney development in fetal life with a dose-dependent relationship. Further studies are needed to assess the underlying mechanisms and whether these differences in fetal kidney volume have postnatal consequences for kidney function and blood pressure.

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

BACKGROUND: glucocorticoid receptor-9ß polymorphism (rs6198) is associated with the susceptibility for cardiovascular disease. AIM: to examine whether the GR-9 ß 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-9ß 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 ß 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.

Early influences on cardiovascular and renal development.

The hypothesis that a developmental component plays a role in subsequent disease initially arose from epidemiological studies relating birth size to both risk factors for cardiovascular disease and actual cardiovascular disease prevalence in later life. The findings that small size at birth is associated with an increased risk of cardiovascular disease have led to concerns about the effect size and the causality of the associations. However, recent studies have overcome most methodological flaws and suggested small effect sizes for these associations for the individual, but an potential important effect size on a population level. Various mechanisms underlying these associations have been hypothesized, including fetal undernutrition, genetic susceptibility and postnatal accelerated growth. The specific adverse exposures in fetal and early postnatal life leading to cardiovascular disease in adult life are not yet fully understood. Current studies suggest that both environmental and genetic factors in various periods of life may underlie the complex associations of fetal growth retardation and low birth weight with cardiovascular disease in later life. To estimate the population effect size and to identify the underlying mechanisms, well-designed epidemiological studies are needed. This review is focused on specific adverse fetal exposures, cardiovascular adaptations and perspectives for new studies.

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.

Cardiac structures track during the first 2 years of life and are associated with fetal growth and hemodynamics: the Generation R Study.

BACKGROUND: The aim of this study is to examine whether cardiac size and function track in early childhood and are associated with fetal and early postnatal growth and blood flow characteristics. METHODS: This study was embedded in a population-based prospective cohort study from fetal life onward. Fetal growth and fetal and placental blood flow parameters in second and third trimester of pregnancy were measured by ultrasound and Doppler. Left cardiac structures and shortening fraction were measured postnatally at the ages of 1.5, 6, and 24 months. Analyses were based on 1,001 children. RESULTS: Left ventricular mass tended to remain in the lowest and highest quartiles from the age of 1.5 to 24 months (odds ratio 1.70, 95% confidence interval [CI] 1.10-2.63) and 2.15 (95% CI 1.41-3.30), respectively. Similar results were found for aortic root diameter and left atrial diameter. Birth weight was positively associated with aortic root diameter (0.08 mm, 95% CI 0.01-0.17; per SD increase) and left ventricular mass (0.65 g, 95% CI 0.09-1.21; per SD increase). Resistance indices of the umbilical and uterine arteries showed weak tendencies toward inverse associations with left cardiac structures. Fetal cardiac output was positively associated with both left atrial diameter (increase of 1.96 mm, 95% CI 1.28-2.64; per mL/min increase) and left ventricular mass (increase of 1.79 g, 95% CI 0.35-3.22; per mL/min increase). CONCLUSIONS: This study suggest moderate tracking of left cardiac structures during the first 2 years and that small size and hemodynamic variations in fetal life have consequences for postnatal cardiac size and function.

Reliability of renal ultrasound measurements in children.

The aim of the investigation reported here was to assess the intraobserver and interobserver variability of renal measurements in children. The study comprised 56 paired measurements in 28 children (median age 7.5 years, range 3.0-15.0 years) without renal or ureterovesical anomalies. Intraobserver and interobserver reproducibility was assessed by repeated measurements of the left and right renal length, width, and thickness. Intraclass correlation coefficients (ICCs) with the corresponding 95% confidence interval (CI) were calculated. Bland and Altman plots were computed to assess the agreement of the measurements. Limits of agreement +/- 2 standard deviations (SD) for the mean differences in renal measurements were derived. Intraobserver ICCs ranged from 0.93 (left and right renal width and right renal thickness) to 0.99 (left renal length), and interobserver ICCs ranged from 0.64 (right renal thickness) to 0.90 (right renal length). Limits of agreement in the Bland and Altman plots ranged from -8.0 to 9.2% (intraobserver left renal width) to the widest limit from -18.0 to 19.2% (interobserver left renal length). Overall, this study demonstrated the good reproducibility and agreement of most renal dimensions in children measured by ultrasound (US). Based on these results, we conclude that US is an appropriate measure to assess renal dimensions in both clinical and epidemiological studies.

Tracking and determinants of kidney size from fetal life until the age of 2 years: the Generation R Study.

BACKGROUND: An adverse fetal environment may lead to smaller kidneys and subsequently kidney disease and hypertension in adulthood. The aims of this study are to examine whether kidney size tracks from fetal life to childhood and whether maternal and fetal characteristics are associated with kidney size at the age of 2 years. STUDY DESIGN: Prospective cohort study from fetal life onward. SETTING & PARTICIPANTS: The study was conducted in a group of 688 infants in Rotterdam, The Netherlands. Entry criteria were singleton, noncomplicated pregnancies, and Dutch ethnicity. PREDICTORS: The maternal characteristics age, height, and prepregnancy weight were measured in early pregnancy. Fetal growth, head circumference, abdominal circumference, femur length and estimated fetal weight, and placental characteristics were assessed in the second and third trimesters. OUTCOMES & MEASUREMENTS: Kidney size, defined as length, width, depth, and volume, was measured in the third trimester of pregnancy and at postnatal ages 6 and 24 months. RESULTS: Overall median gestational age was 40.3 weeks (95% range, 36.0 to 42.3 weeks), and mean birth weight was 3,536 +/- 524 (SD) g. Children tended to remain in the lowest and highest quartiles of kidney volume from the third trimester to the age of 2 years (odds ratio, 2.05; 95% confidence interval, 1.38 to 3.06; odds ratio, 3.29; 95% confidence interval, 2.22 to 4.87, respectively). Maternal height and prepregnancy weight were associated positively with kidney volume at the age of 2 years. Third-trimester fetal head circumference, abdominal circumference, and estimated weight and postnatal length were associated positively with kidney volume at the age of 2 years. Preferential fetal blood flow to the brain was associated with smaller kidneys. LIMITATIONS: Kidney measurements successfully performed in only 86% of children. CONCLUSIONS: Small kidney size in fetal life tends to persist in early childhood. Maternal anthropometrics and fetal biometrics and blood flow patterns are associated with kidney size in childhood. Follow-up studies are needed to examine whether these variations in kidney size are related to kidney function and blood pressure in later life.

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.