Katy Pike | University of Oxford (original) (raw)

Papers by Katy Pike

Preterm birth, low birth weight and high infant weight gain are associated with increased risks o... more Preterm birth, low birth weight and high infant weight gain are associated with increased risks of childhood asthma. An important underlying pathway might be smaller airways and subsequent lower lung function. We examined the association of early growth characteristics with the risk of lower lung function, using data from 24,715 children of 24 European birth cohorts. Studies were eligible if they included children from 1989 onwards, had information on gestational age, birth weight or infant weight gain, and lung function (FEV1, FVC, FEF25-75, FEF75) at age 4-18 years. Random-effect meta-analyses were used with individual participant data and pooled effect estimates. Younger gestational age and lower birth weight were associated with lower lung function values (p-values Younger gestational age, lower weight at birth and higher infant weight gain are associated with lower lung function in childhood. Smaller airways might be partly responsible for associations of early growth characteristics with asthma.

Journal of Epidemiology and Community Health, 2016

Background Wheeze is one of the most common chronic conditions in childhood. Understanding its so... more Background Wheeze is one of the most common chronic conditions in childhood. Understanding its social risk factors is important for prevention. However, studies examining inequalities in wheeze have shown inconclusive results. This is potentially due to the complexities of differentiating between wheezing illnesses, which have different underlying causes, many associated with socio-economic disadvantage but some with advantage (e.g. atopy). We therefore investigated inequalities in typologies of wheeze and atopy, using longitudinal data and objective atopic status. Methods We used data from the Southampton Women’s Survey (SWS), a population-based study of non-pregnant 20–34 year (y) old women, resident in Southampton (UK), 1998–2002. Offspring, born 1998–2007, were followed through childhood. Information included maternal-reported wheeze (6 months (m), 12 m, 2 y, 3 y, 6 y), and skin prick tests for atopic sensitisation (12 m, 3 y, 6 y). Longitudinal typologies of wheeze and atopy were created using latent class analysis in children with complete data at 6 y (n = 1258; 40% of original recruits, 69% of those seen at 6 y). Two- to seven-class measures were assessed based on model fit and interpretability. Children were assigned to the class to which they had the highest probability of belonging. Socio-economic differences in wheeze were examined with relative risk ratios (RRRs [95% confidence intervals]), according to maternal highest academic qualifications (GCSEs/None; A-Levels; Diploma/Degree). Sensitivity analyses included: weighting analyses to account for uncertainty of class assignment, using an alternative measure of socio-economic circumstances (maternal occupation), and imputing missing data. Analyses were conducted in Stata 13.0 (and ‘SAS PROC LCA’ plug-in). Results Five classes of wheeze and atopy emerged: ‘No Wheeze, No Atopy’ (53%), ‘Non-atopic Early Wheeze’ (15%); ‘Non-atopic Remitting Wheeze’ (16%); ‘Atopic Increasing/Persistent Wheeze’ (7%); ‘Atopy Only’ (10%). Compared with children whose mothers had GCSEs/None, those whose mothers had a Diploma/Degree were less likely to experience ‘Non-atopic Remitting Wheeze’ (RRR = 0.55 [0.37–0.82]), no less likely to experience ‘Non-atopic Early Wheeze’ (1.13 [0.77–1.70]), and more likely to have ‘Atopy Only’ (1.79 [1.12–2.89]). In analyses restricted to atopic children, those whose mothers had a Diploma/Degree were less likely to develop ‘Atopic Increasing/Persistent Wheeze’ (0.49 [0.24–0.98]). There were few differences between those with A-levels and GCSEs/None. Sensitivity analyses produced similar patterns. Conclusion Children of mothers with lower educational qualifications were more likely to experience non-atopic remitting wheeze and, if they had atopy, to develop persistent wheeze. These findings require replication in larger samples and beyond the age of 6 y (including in the SWS). Future research to explain these inequalities will help shape interventions.

Body: Background Low birth weight, preterm birth and rapid infant growth seem to be associated wi... more Body: Background Low birth weight, preterm birth and rapid infant growth seem to be associated with increased risks of childhood asthma. We examined the association of birth and infant growth characteristics with the risks of preschool wheezing and school age asthma using data from 147,252 subjects of 31 European cohort studies. Methods Studies were eligible if they included children from 1989 onwards, had

Springer eBooks, Nov 22, 2020

Bronchiectasis is a significant cause of morbidity and mortality. It is the end point of a pathol... more Bronchiectasis is a significant cause of morbidity and mortality. It is the end point of a pathological process. We should be aiming to identify at risk patients before they develop bronchiectasis and to treat them aggressively to prevent disease progression. With improved social conditions and health care, infective causes of bronchiectasis have diminished in higher-income countries, and genetic causes are therefore relatively more common. The underlying cause of bronchiectasis should always be sought and readdressed, for example as discoveries of innate immune defects are made. ‘Idiopathic bronchiectasis’ should be a diagnosis of last resort. This chapter reviews potential genetic causes of bronchiectasis and suggests a plan for investigating the underlying aetiology. Management is discussed but it is important to note that suggested treatment strategies are often extrapolated from evidence in bronchiectasis associated with cystic fibrosis; this is likely to be inappropriate in diseases of differing pathophysiology. Rare lung diseases need to be moved out of the ‘orphan’ category by instigating multi-centre, multi-national clinical trials and producing disease-specific evidence-based guidelines

Background Studies exploring the relationship between prenatal vitamin D exposure and childhood a... more Background Studies exploring the relationship between prenatal vitamin D exposure and childhood asthma have yielded conflicting results. Higher vitamin D intake during pregnancy has been shown to lower the risk of childhood wheeze, yet a study of maternal late-pregnancy serum 25-hydroxyvitamin D suggested higher serum concentrations may be associated with increased childhood asthma. Objective To assess the relationship between mothers' serum 25-hydroxyvitamin D status and asthma and wheeze phenotypes in their children at age 6 years. Also to explore the relationship between maternal 25hydroxyvitamin D status and objective measures of childhood atopy and lung function. Methods Serum 25-hydroxyvitamin D was measured at 34 weeks' gestation in the mothers of 860 children born at term. Wheeze was classified as either transient or persistent/late using questionnaire data collated from 6, 12, 24 and 36 months and 6 years. At 6 years spirometry was performed and atopic status was determined by skin prick testing, exhaled nitric oxide was measured in 451 children and bronchial hyperresponsiveness in 216 children. Results There were no significant associations between maternal late-pregnancy 25-hydroxyvitamin D status and either asthma or wheeze at age 6 years. Maternal vitamin D status was not associated with transient or persistent/late wheeze; no significant association was found between persistent/late wheeze when subdivided according to atopic status. No associations were found with skin sensitisation or lung function. Conclusions This study provides no evidence that exposure to higher concentrations of 25-hydroxyvitamin D in maternal serum during late pregnancy increases the risk of childhood asthma, wheeze or atopy.

Background In 1995 the Tucson Children's Respiratory Study (TCRS) identified clinically distinct ... more Background In 1995 the Tucson Children's Respiratory Study (TCRS) identified clinically distinct phenotypes amongst early wheezers; the Avon Longitudinal Study of Parents And Children (ALSPAC) has recently reexamined these. Objectives To validate statistically derived ALSPAC phenotypes in the Southampton Women's Survey (SWS) using infant and 6 year lung function, and allergic sensitisation at 1, 3 and 6 years, comparing these with TCRS phenotypes. Methods Complete 6 year follow-up data were available for 926 children, selected from 1973 infants born to 12,579 women characterised pre-conception. 95 children had V'maxFRC and FEV0.4 measured age 5-14 weeks using rapid compression/raised volume techniques. At 6 years we performed spirometry (n=791), fractional exhaled nitric oxide (FeNO, n=589) and methacholine challenge (n=234). Skin prick testing was performed at 12m, 3 and 6 years (n=1494, 1255, 699, respectively). Using wheeze status questionnaire data at 6m, 12m, 2, 3 and 6 years we classified children into TCRS (never, transient early, persistent, late-onset) and ALSPAC based groups (never, early, transient, intermediate-onset, late-onset, persistent). Results Amongst ALSPAC groups, persistent and late-onset wheeze were associated with atopy at 3 and 6 years, whilst intermediate-onset wheeze showed earlier atopic association at 1 year; all three were associated with FeNO at 6 years. Persistent wheezers had lower infant (V'maxFRC p<0.05) and 6 year lung function (FEV1, FEV1/FVC and FEF25-75, p<0.05), whilst late and intermediate-onset wheezers showed no lung function deficits. Transient wheezers were non-atopic but showed persistent lung function deficits (V'maxFRC in infancy, FEV1 and FEF25-75 at 6 years, all p<0.05). Those who wheezed only in the first year (early phenotype) showed no lung function deficits. No associations were seen with 6 years bronchial hyper-responsiveness or infancy FEV0.4. Conclusion SWS cohort data validates the statistically derived ALSPAC 6-class model. In particular, lung function and atopy successfully differentiate persistent, late-onset and intermediate-onset wheeze, whilst the Tucson 'transient early' wheeze phenotype can be sub-classified into groups that reflect early lung function. Since the 4-class model fails to adequately differentiate phenotypes based on lung function and atopy, we propose that strong consideration be given to using the 6-class paradigm for longitudinal outcome work in wheezing with onset in early life.

Respiratory function technologists/scient.

Paediatric asthma and allergy

Paediatric respiratory epidemiology

Paediatric Asthma and Allergy

Paediatric Respiratory Epidemiology

European Respiratory Journal, 2016

Thorax, 2012

Background Many factors have been related to the development of childhood asthma but there is inc... more Background Many factors have been related to the development of childhood asthma but there is inconsistency between studies. Objective To understand how early life factors are linked to the development of the various asthma phenotypes at age 6 years in the Southampton Women's Survey (SWS) children's cohort. Methods Data was collected from 940 children and their parents, primarily through questionnaires during pregnancy and at 6m, 1, 3 and 6 years. Prevalent asthma was defined by a doctor's diagnosis and a wheezing episode in the last year. Data was analysed using STATA v9. A relative risk analysis using a univariate approach was undertaken, followed by a multivariate analysis. Results Both maternal (RR=1.61, p=0.041) and paternal (RR=2.05, p=0.002) atopic disease increased the risk of asthma at age 6 years. The risk increased with atopy, defined as a positive skin prick test, at 3 years (RR=3.05, p<0.001) and with wheeze in the first 3 years (RR=8.79, p<0.001). Episodes of bronchiolitis and chest infections were associated, in a dose-dependent manner, with the risk of asthma (RR=1.50, p=0.022). Predictors in the multivariate model were wheeze in the first 3 years (RR=10.74, p<0.001), atopy (RR=2.87, p<0.001) and maternal atopy (RR=2.22, p=0.011).When asthma at age 6 years was split into atopic and non-atopic asthma, the predictors were very different. Atopic asthma was associated with paternal atopy (RR=4.13, p=0.002), male sex (RR=2.56, p=0.030), atopy at 3 years (RR=10.31, p<0.001) and wheeze in the first 3 years (RR=5.91, p=0.004). In the multivariate analysis, the following were predictive: wheeze in the first 3 years (RR=13.55, p=0.012), atopy at 3 years (RR=10.13,<0.001), paternal atopy (RR=2.97, p=0.017) and a 12 month infant dietary pattern that follows current guidelines (RR=1.79, p=0.016). For non-atopic asthma, bronchiolitis or chest infections (RR=1.76, p=0.047), wheeze in the first 3 years (RR=20.69, p=0.003) and tobacco smoke exposure at 6 years (RR=2.16, p=0.035) increased the risk. Only wheeze in the first 3 years remained in the multivariate model. Conclusions Different hereditary and early life factors modify the risk of atopic and non-atopic asthma at 6 years of age. This suggests that these two asthma phenotypes have different pathophysiologies.

npj Primary Care Respiratory Medicine, 2016

Inappropriate prescribing in primary care was implicated in nearly half of asthma deaths reviewed... more Inappropriate prescribing in primary care was implicated in nearly half of asthma deaths reviewed in the UK's recent National Review of Asthma Deaths. Using anonymised EMIS-Web data for 139 ethnically diverse general practices (total population 942,511) extracted from the North and East London Commissioning Support Unit, which holds hospital Secondary Uses Services (SUS)-linked data, we examined the prevalence of over-prescribing of short-acting β 2-agonist inhalers (SABA), under-prescribing of inhaled corticosteroid (ICS) inhalers and solo prescribing of long-acting β 2-agonists (LABA) to assess the risk of hospitalisation for people with asthma for 1 year ending August 2015. In a total asthma population of 35,864, multivariate analyses in adults showed that the risk of admission increased with greater prescription of SABA inhalers above a baseline of 1-3 (4-12 SABA: odds ratio (OR) 1.71; 95% confidence interval (CI) 1.20-2.46, ⩾ 13 SABA: OR 3.22; 95% CI 2.04-5.07) with increasing British Thoracic Society step (Step 3: OR 2.90; 95% CI 1.79-4.69, Step 4/5: OR 9.42; 95% CI 5.27-16.84), and among Black (OR 2.30; 95% CI 1.64-3.23) and south Asian adult populations (OR 1.83; 95% CI 1.36-2.47). Results in children were similar, but risk of hospitalisation was not related to ethnic group. There is a progressive risk of hospital admission associated with the prescription of more than three SABA inhalers a year. Adults (but not children) from Black and South Asian groups are at an increased risk of admission. Further work is needed to target care for these at-risk groups.

The Journal of allergy and clinical immunology, Jan 5, 2015

Children born preterm or with a small size for gestational age are at increased risk for childhoo... more Children born preterm or with a small size for gestational age are at increased risk for childhood asthma. We sought to assess the hypothesis that these associations are explained by reduced airway patency. We used individual participant data of 24,938 children from 24 birth cohorts to examine and meta-analyze the associations of gestational age, size for gestational age, and infant weight gain with childhood lung function and asthma (age range, 3.9-19.1 years). Second, we explored whether these lung function outcomes mediated the associations of early growth characteristics with childhood asthma. Children born with a younger gestational age had a lower FEV1, FEV1/forced vital capacity (FVC) ratio, and forced expiratory volume after exhaling 75% of vital capacity (FEF75), whereas those born with a smaller size for gestational age at birth had a lower FEV1 but higher FEV1/FVC ratio (P < .05). Greater infant weight gain was associated with higher FEV1 but lower FEV1/FVC ratio and F...

Paediatric respiratory reviews, Jan 8, 2014

In developed countries most preterm births occur between 34 and 37 weeks' gestation. Deliveri... more In developed countries most preterm births occur between 34 and 37 weeks' gestation. Deliveries during this 'late preterm' period are increasing and, since even mild prematurity is now recognised to be associated with adverse health outcomes, this presents healthcare challenges. Respiratory problems associated with late preterm birth include neonatal respiratory distress, severe RSV infection and childhood wheezing. Late preterm birth prematurely interrupts in utero lung development and is associated with maternal and early life factors which adversely affect the developing respiratory system. This review considers 1) mechanisms underlying the association between late preterm birth and impaired respiratory development, 2) respiratory morbidity associated with late preterm birth, particularly long-term outcomes, and 3) interventions which might protect respiratory development by addressing risk factors affecting the late preterm population, including maternal smoking, ear...