Effects on mortality of shielding clinically extremely vulnerable patients in Liverpool, UK, during the COVID-19 pandemic.

OBJECTIVE: This study evaluates the impact of England's COVID-19 shielding programme on mortality in the City of Liverpool in North West England. STUDY DESIGN: Shielded and non-shielded people are compared using data from linked routine health records on all people registered with a general practitioner in Liverpool from April 2020 to June 2021. METHODS: A discrete time hazard model and interactions between the shielding status and the periods of higher risk of transmission are used to explore the effects of shielding across the major phases of the COVID-19 pandemic. RESULTS: Shielding was associated with a 34% reduction in the risk of dying (HR = 0.66, 95% CI: 0.58 to 0.76) compared with a propensity-matched non-shielded group. Shielding appeared to reduce mortality during the first and third waves, but not during the second wave, where shielding was not mandated by the government. The effects were similar for males and females, but more protective for those living in the least deprived areas of Liverpool. CONCLUSIONS: It is likely that the shielding programme in Liverpool saved lives, although this seems to have been a little less effective in more deprived areas. A comprehensive programme for identifying vulnerable groups and providing them with advice and support is likely to be important for future respiratory virus pandemics. Additional support may be necessary for socio-economically disadvantaged groups to avoid increased inequalities.

Defining trajectories of response in patients with psoriasis treated with biologic therapies.

BACKGROUND: The effectiveness and cost-effectiveness of biologic therapies for psoriasis are significantly compromised by variable treatment responses. Thus, more precise management of psoriasis is needed. OBJECTIVES: To identify subgroups of patients with psoriasis treated with biologic therapies, based on changes in their disease activity over time, that may better inform patient management. METHODS: We applied latent class mixed modelling to identify trajectory-based patient subgroups from longitudinal, routine clinical data on disease severity, as measured by the Psoriasis Area and Severity Index (PASI), from 3546 patients in the British Association of Dermatologists Biologics and Immunomodulators Register, as well as in an independent cohort of 2889 patients pooled across four clinical trials. RESULTS: We discovered four discrete classes of global response trajectories, each characterized in terms of time to response, size of effect and relapse. Each class was associated with differing clinical characteristics, e.g. body mass index, baseline PASI and prevalence of different manifestations. The results were verified in a second cohort of clinical trial participants, where similar trajectories following the initiation of biologic therapy were identified. Further, we found differential associations of the genetic marker HLA-C*06:02 between our registry-identified trajectories. CONCLUSIONS: These subgroups, defined by change in disease over time, may be indicative of distinct endotypes driven by different biological mechanisms and may help inform the management of patients with psoriasis. Future work will aim to further delineate these mechanisms by extensively characterizing the subgroups with additional molecular and pharmacological data.

A national initiative in data science for health: an evaluation of the UK Farr Institute.

OBJECTIVE: To evaluate the extent to which the inter-institutional, inter-disciplinary mobilisation of data and skills in the Farr Institute contributed to establishing the emerging field of data science for health in the UK. DESIGN AND OUTCOME MEASURES: We evaluated evidence of six domains characterising a new field of science:defining central scientific challenges,demonstrating how the central challenges might be solved,creating novel interactions among groups of scientists,training new types of experts,re-organising universities,demonstrating impacts in society.We carried out citation, network and time trend analyses of publications, and a narrative review of infrastructure, methods and tools. SETTING: Four UK centres in London, North England, Scotland and Wales (23 university partners), 2013-2018. RESULTS: 1. The Farr Institute helped define a central scientific challenge publishing a research corpus, demonstrating insights from electronic health record (EHR) and administrative data at each stage of the translational cycle in 593 papers with at least one Farr Institute author affiliation on PubMed. 2. The Farr Institute offered some demonstrations of how these scientific challenges might be solved: it established the first four ISO27001 certified trusted research environments in the UK, and approved more than 1000 research users, published on 102 unique EHR and administrative data sources, although there was no clear evidence of an increase in novel, sustained record linkages. The Farr Institute established open platforms for the EHR phenotyping algorithms and validations (>70 diseases, CALIBER). Sample sizes showed some evidence of increase but remained less than 10% of the UK population in primary care-hospital care linked studies. 3.The Farr Institute created novel interactions among researchers: the co-author publication network expanded from 944 unique co-authors (based on 67 publications in the first 30 months) to 3839 unique co-authors (545 papers in the final 30 months). 4. Training expanded substantially with 3 new masters courses, training >400 people at masters, short-course and leadership level and 48 PhD students. 5. Universities reorganised with 4/5 Centres established 27 new faculty (tenured) positions, 3 new university institutes. 6. Emerging evidence of impacts included: > 3200 citations for the 10 most cited papers and Farr research informed eight practice-changing clinical guidelines and policies relevant to the health of millions of UK citizens. CONCLUSION: The Farr Institute played a major role in establishing and growing the field of data science for health in the UK, with some initial evidence of benefits for health and healthcare. The Farr Institute has now expanded into Health Data Research (HDR) UK but key challenges remain including, how to network such activities internationally.

Assessing the severity of Type 2 diabetes using clinical data-based measures: a systematic review.

AIMS: To identify and critically appraise measures that use clinical data to grade the severity of Type 2 diabetes. METHODS: We searched MEDLINE, Embase and PubMed between inception and June 2018. Studies reporting on clinical data-based diabetes-specific severity measures in adults with Type 2 diabetes were included. We excluded studies conducted solely in participants with other types of diabetes. After independent screening, the characteristics of the eligible measures including design and severity domains, the clinical utility of developed measures, and the relationship between severity levels and health-related outcomes were assessed. RESULTS: We identified 6798 studies, of which 17 studies reporting 18 different severity measures (32 314 participants in 17 countries) were included: a diabetes severity index (eight studies, 44%); severity categories (seven studies, 39%); complication count (two studies, 11%); and a severity checklist (one study, 6%). Nearly 89% of the measures included diabetes-related complications and/or glycaemic control indicators. Two of the severity measures were validated in a separate study population. More severe diabetes was associated with increased healthcare costs, poorer cognitive function and significantly greater risks of hospitalization and mortality. The identified measures differed greatly in terms of the included domains. One study reported on the use of a severity measure prospectively. CONCLUSIONS: Health records are suitable for assessment of diabetes severity; however, the clinical uptake of existing measures is limited. The need to advance this research area is fundamental as higher levels of diabetes severity are associated with greater risks of adverse outcomes. Diabetes severity assessment could help identify people requiring targeted and intensive therapies and provide a major benchmark for efficient healthcare services.

Combining Health Data Uses to Ignite Health System Learning.

OBJECTIVES: In this paper we aim to characterise the critical mass of linked data, methods and expertise required for health systems to adapt to the needs of the populations they serve - more recently known as learning health systems. The objectives are to: 1) identify opportunities to combine separate uses of common data sources in order to reduce duplication of data processing and improve information quality; 2) identify challenges in scaling-up the reuse of health data sufficiently to support health system learning. METHODS: The challenges and opportunities were identified through a series of e-health stakeholder consultations and workshops in Northern England from 2011 to 2014. From 2013 the concepts presented here have been refined through feedback to collaborators, including patient/citizen representatives, in a regional health informatics research network (www.herc.ac.uk). RESULTS: Health systems typically have separate information pipelines for: 1) commissioning services; 2) auditing service performance; 3) managing finances; 4) monitoring public health; and 5) research. These pipelines share common data sources but usually duplicate data extraction, aggregation, cleaning/preparation and analytics. Suboptimal analyses may be performed due to a lack of expertise, which may exist elsewhere in the health system but is fully committed to a different pipeline. Contextual knowledge that is essential for proper data analysis and interpretation may be needed in one pipeline but accessible only in another. The lack of capable health and care intelligence systems for populations can be attributed to a legacy of three flawed assumptions: 1) universality: the generalizability of evidence across populations; 2) time-invariance: the stability of evidence over time; and 3) reducibility: the reduction of evidence into specialised sub-systems that may be recombined. CONCLUSIONS: We conceptualize a population health and care intelligence system capable of supporting health system learning and we put forward a set of maturity tests of progress toward such a system. A factor common to each test is data-action latency; a mature system spawns timely actions proportionate to the information that can be derived from the data, and in doing so creates meaningful measurement about system learning. We illustrate, using future scenarios, some major opportunities to improve health systems by exchanging conventional intelligence pipelines for networked critical masses of data, methods and expertise that minimise data-action latency and ignite system-learning.

Influenza, influenza-like symptoms and their association with cardiovascular risks: a systematic review and meta-analysis of observational studies.

AIMS: To synthesise the evidence relating influenza and influenza-like symptoms to the risks of myocardial infarction (MI), heart failure (HF) and stroke. METHODS: We conducted a systematic review and meta-analysis of the evidence relating influenza and influenza-like symptoms to the risks of MI, HF and stroke. We systematically searched all MEDLINE and EMBASE entries up to August 2014 for studies of influenza vs. the cardiovascular outcomes above. We conducted random effects meta-analysis using inverse variance method for pooled odds ratios (OR) and evaluated statistical heterogeneity using the I(2) statistic. RESULTS: We identified 12 studies with a total of 84,003 participants. The pooled OR for risk of MI vs. influenza (serologically confirmed) was 1.27 (95% CI, confidence interval 0.54-2.95), I(2)  = 47%, which was significant for the only study that adjusted for confounders (OR 5.50, 95% CI 1.31-23.13). The pooled OR for risk of MI vs. influenza-like symptoms was 2.17 (95% CI 1.68-2.80), I(2)  = 0%, which was significant for both unadjusted (OR 2.23, 95% CI 1.65-3.01, five studies) and adjusted studies (OR 2.01, 95% CI 1.24-3.27, two studies). We found one study that evaluated stroke risk, one study in patients with HF, and one that evaluated mortality from MI - all of these studies suggested increased risks of events with influenza-like symptoms. CONCLUSIONS: There is an association between influenza-like illness and cardiovascular events, but the relationship is less clear with serologically diagnosed influenza. We recommend renewed efforts to apply current clinical guidelines and maximise the uptake of annual influenza immunisation among patients with cardiovascular diseases, to decrease their risks of MI and stroke.

Slowing down of adult body mass index trend increases in England: a latent class analysis of cross-sectional surveys (1992-2010).

BACKGROUND: The prevalence of excess body weight, commonly measured as body mass index (BMI)≥25 kg m(-2), has increased substantially in many populations worldwide over the past three decades, but the rate of increase has slowed down in some western populations. OBJECTIVE: We address the hypothesis that the slowing down of BMI trend increases in England reflects a majority sub-population resistant to further BMI elevation. DESIGN: Pseudo-panel data derived from annual cross-sectional surveys, the Health Surveys for England (1992-2010). Trends in median BMI values were explored using regression models with splines, and gender-specific mixture model (latent class analysis) were fit to take an account of increasing BMI distribution variance with time and identify hidden subgroups within the population. SUBJECTS: BMI was available for 164 155 adults (men: 76 382; women: 87 773). RESULTS: Until 2001, the age-adjusted yearly increases in median BMI were 0.140 and 0.139 kg m(-2) for men and women, respectively, decreasing thereafter to 0.073 and 0.055 kg m(-2) (differences between time periods, both P-values<0.0001). The mixture model identified two components--a normal BMI and a high BMI sub-population--the proportions for the latter were 23.5% in men and 33.7% in women. The remaining normal BMI populations were 'resistant' with minimal increases in mean BMI values over time. By age, mean BMI values in the normal BMI sub-population increased greatest between 20 and 34 years for men; for women, the increases were similar throughout age groups (slope differences, P<0.0001). CONCLUSION: In England, recent slowing down of adult BMI trend increases can be explained by two sub-populations--a high BMI sub-population getting 'fatter' and a majority 'resistant' normal BMI sub-population. These findings support a targeted, rather than a population-wide, policy to tackle the determinants of obesity.

Trustworthy reuse of health data: a transnational perspective.

BACKGROUND: The widespread adoption of electronic health records (EHRs) is accelerating the collection of sensitive clinical data. The availability of these data raises privacy concerns, yet sharing the data is essential for public health, longitudinal patient care, and clinical research. METHOD: Following previous work in the United States [1,2], the International Medical Informatics Association convened the 2012 European Summit on Trustworthy Reuse of Health Data. Over 100 delegates representing national governments, academia, patient groups, industry, and the European Commission participated. In all, 21 countries were represented. The agenda was designed to solicit a wide range of perspectives on trustworthy reuse of health data from the participants. RESULTS AND CONCLUSIONS: Delegates agreed that the "government" should provide oversight, that the reuse should be "fully regulated," and that the patient should be "fully informed." One important reflection was that doing nothing will have negative implications across the European Union (EU). First, continued fragmented parallel non-standards-based developments in multiple sectors entail a substantial duplication of costs and human effort. Second, a failure to work jointly across the stakeholders on common policy frameworks will forego a crucial opportunity to boost key EU markets (pharmaceuticals, health technology and devices, and eHealth solutions) and counter global competition. Finally, and crucially, the lack of harmonized policy across EU nations for trustworthy reuse of health data risks patient safety. The productive dialog, initiated with multiple stakeholders from government, academia, and industry, will have to continue, in order to address the many remaining issues outlined in this white paper.

Prevention of breast cancer in the context of a national breast screening programme.

Breast cancer is not only increasing in the west but also particularly rapidly in eastern countries where traditionally the incidence has been low. The rise in incidence is mainly related to changes in reproductive patterns and lifestyle. These trends could potentially be reversed by defining women at greatest risk and offering appropriate preventive measures. A model for this approach was the establishment of Family History Clinics (FHCs), which have resulted in improved survival in younger women at high risk. New predictive models of risk that include reproductive and lifestyle factors, mammographic density and measurement of risk-associated single nucleotide polymorphisms (SNPs) may give more precise information concerning risk and enable better targeting for mammographic screening programmes and of preventive measures. Endocrine prevention using anti-oestrogens and aromatase inhibitors is effective, and observational studies suggest lifestyle modification may also be effective. However, referral to FHCs is opportunistic and predominantly includes younger women. A better approach for identifying older women at risk may be to use national breast screening programmes. Here were described pilot studies to assess whether the routine assessment of breast cancer risk is feasible within a population-based screening programme, whether the feedback and advice on risk-reducing interventions would be welcomed and taken up, and to consider whether the screening interval should be modified according to breast cancer risk.

IMPACT: a generic tool for modelling and simulating public health policy.

BACKGROUND: Populations are under-served by local health policies and management of resources. This partly reflects a lack of realistically complex models to enable appraisal of a wide range of potential options. Rising computing power coupled with advances in machine learning and healthcare information now enables such models to be constructed and executed. However, such models are not generally accessible to public health practitioners who often lack the requisite technical knowledge or skills. OBJECTIVES: To design and develop a system for creating, executing and analysing the results of simulated public health and healthcare policy interventions, in ways that are accessible and usable by modellers and policy-makers. METHODS: The system requirements were captured and analysed in parallel with the statistical method development for the simulation engine. From the resulting software requirement specification the system architecture was designed, implemented and tested. A model for Coronary Heart Disease (CHD) was created and validated against empirical data. RESULTS: The system was successfully used to create and validate the CHD model. The initial validation results show concordance between the simulation results and the empirical data. CONCLUSIONS: We have demonstrated the ability to connect health policy-modellers and policy-makers in a unified system, thereby making population health models easier to share, maintain, reuse and deploy.

Body mass index in young children and allergic disease: gender differences in a longitudinal study.

BACKGROUND: The increase in allergic diseases has occurred in parallel with the obesity epidemic, suggesting a possible association. OBJECTIVE: We investigated the relationship of body mass index (BMI) up to age 8 years with allergic disease within a birth cohort. METHODS: Children were followed from birth and were reviewed at age 3, 5 and 8 years (n=731; male 406). Parents completed questionnaires; children were weighed, measured, skin prick tested and examined. RESULTS: Increasing BMI at 3, 5 and 8 years increased the risk of current wheezing at the corresponding age (odds ratio [95% confidence interval] per standardized deviation score: age 3, 1.26 [1.04-1.53], P=0.02; age 5, 1.33 [1.06-1.67], P=0.02; age 8, 1.27 [1.0-1.62], P=0.05). The effect of BMI on wheeze at age 8 years differed between boys and girls, with a significant positive association in girls, but not in boys (P=0.04 for interaction). The effect of BMI at earlier ages on current or subsequent wheezing did not differ significantly between genders. Increasing BMI significantly increased the risk of physician-diagnosed eczema at age 5 (1.23 [1.04-1.47], P=0.02) and 8 (1.23 [1.03-1.45], P=0.02), with a significant interaction between gender and BMI at age 5 (P=0.04). There was no association between BMI and sensitization. Being overweight at age 3 years was significantly associated with late-onset wheeze (3.83 [1.51-9.75], P=0.005), persistent wheeze (4.15 [2.07-8.32], P<0.001) and persistent eczema (1.79 [1.03-3.13], P=0.04) in both boys and girls. CONCLUSIONS: Being overweight is associated with an increased risk of allergic disease in childhood. However, the strength of the association varies with the gender, age and atopic phenotype.

Supporting creativity and appreciation of uncertainty in exploring geo-coded public health data.

BACKGROUND AND OBJECTIVES: We present a prototype visualisation tool, ADVISES (Adaptive Visualization for e-Science), designed to support epidemiologists and public health practitioners in exploring geo-coded datasets and generating spatial epidemiological hypotheses. The tool is designed to support creative thinking while providing the means for the user to evaluate the validity of the visualization in terms of statistical uncertainty. We present an overview of the application and the results of an evaluation exploring public health researchers' responses to maps as a new way of viewing familiar data, in particular the use of thematic maps with adjoining descriptive statistics and forest plots to support the generation and evaluation of new hypotheses. METHODS: A series of qualitative evaluations involved one experienced researcher asking 21 volunteers to interact with the system to perform a series of relatively complex, realistic map-building and exploration tasks, using a 'think aloud' protocol, followed by a semi-structured interview The volunteers were academic epidemiologists and UK National Health Service analysts. RESULTS: All users quickly and confidently created maps, and went on to spend substantial amounts of time exploring and interacting with system, generating hypotheses about their maps. CONCLUSIONS: Our findings suggest that the tool is able to support creativity and statistical appreciation among public health professionals and epidemiologists building thematic maps. Software such as this, introduced appropriately, could increase the capability of existing personnel for generating public health intelligence.

The high prevalence of unrecognized anaemia in patients with diabetes and chronic kidney disease: a population-based study.

BACKGROUND: Anaemia occurs early in the course of diabetes-related chronic kidney disease (CKD). There is little evidence about the prevalence of anaemia in people with diabetes. The aim of this study was to assess the prevalence of anaemia, by stage of CKD, in the general diabetic population. METHODS: Haemoglobin (Hb) was measured on all glycated haemoglobin (HbA1c) samples and the most recent (< 4 months) estimated glomerular filtration rate (eGFR) was obtained. Anaemia (at treatment level) was defined as Hb < 110 g/l or the use of erythropoetic stimulating agents (ESA). RESULTS: Twelve per cent (10-14%) of people had Hb < 110 g/l. The prevalence of anaemia increased progressively with worsening CKD. People with CKD stage 3 accounted for the largest number of people with anaemia; 18% (95% CI 13-24%) had Hb < 110 g/l. Those with eGFR < 60 ml/min/1.73 m2 and not on ESA or dialysis were four (2-7) times more likely than patients with better renal function to have Hb < 110 g/l. The relation between Hb and eGFR became approximately linear below an eGFR of 83 ml/min/1.73 m2, where, for every 1 ml/min/1.73 m2 fall in eGFR, there was a 0.4 (0.3-0.5) g/l fall in haemoglobin. CONCLUSIONS: This study demonstrates that anaemia, at levels where treatment is indicated, occurs commonly in people with diabetes and CKD stage 3 or worse. The screening for anaemia in current diabetes management should be extended.

Cardiorespiratory fitness and body mass index of 9-11-year-old English children: a serial cross-sectional study from 1998 to 2004.

OBJECTIVE: To examine the changes over time in cardiorespiratory fitness and body mass index (BMI) of children. DESIGN: Serial cross-sectional, population-based study. SETTING: Primary schools in Liverpool, UK. PARTICIPANTS: A total of 15,621 children (50% boys), representing 74% of eligible 9-11-year olds in the annual school cohorts between 1998/9 and 2003/4, who took part in a 20m multi-stage shuttle run test (20mMST). MAIN OUTCOME MEASURES: Weight, height, BMI (kg/m(2)) and obesity using the International Obesity Taskforce definition. RESULTS: Median (95% confidence interval) 20mMST score (number of runs) fell in boys from 48.9 (47.9-49.9) in 1998/9 to 38.1 (36.8-39.4) in 2003/4, and in girls from 35.8 (35.0-36.6) to 28.1 (27.2-29.1) over the same period. Fitness scores fell across all strata of BMI (P<0.001). Moreover, BMI increased over the same 6-year period even among children in fittest third of 20mMST. CONCLUSION: In a series of uniform cross-sectional assessments of school-aged children, BMI increased whereas cardiorespiratory fitness levels decreased within a 6-year period. Even among lean children, fitness scores decreased. Public health measures to reduce obesity, such as increasing physical activity, may help raise fitness levels among all children - not just the overweight or obese.

Body mass index has risen more steeply in tall than in short 3-year olds: serial cross-sectional surveys 1988-2003.

OBJECTIVE: To monitor the changing relationship between body mass index (BMI) and height in young children. DESIGN: Annual cross-sectional surveys using health-visitor-collected routine data 1988-2003. SETTING: Wirral, England. PARTICIPANTS: Fifty thousand four hundred and fifty-five children (49% female) each measured once at the age of 3 years. MAIN OUTCOME MEASURES: Weight, height and derived BMI (weight/height(2)) adjusted for age and sex (British 1990 revised reference) using standard deviation scores. RESULTS: From 1988 to 2003, mean BMI increased by 0.7 kg/m(2), whereas mean height fell by 0.5 cm. Over the same period, the weight-height correlation rose from 0.59 to 0.71 (P<0.0001) owing to BMI increasing faster in the taller than the shorter children. Among the shortest 10% of children, mean BMI rose by 0.12 (95% confidence interval: -0.05-0.28) kg/m(2) as against 1.38 (1.19-1.56) kg/m(2) among the tallest 10%, a 12-fold difference. Adjustment for age, sex, seasonality, birth-weight and deprivation did not alter the findings. CONCLUSIONS: Among 3-year-old children in Wirral, where BMI has been rising for 16 years, the largest increase in BMI has occurred in the tallest children, whereas in the shortest BMI has hardly changed. Tall stature has, therefore, become important for child obesity. It suggests a drive to increasing adiposity in young children that involves both growth and appetite, with fast growing and hungrier children now more exposed to the 'obesogenic' environment.

Effect of breast feeding on risk of coeliac disease: a systematic review and meta-analysis of observational studies.

BACKGROUND: Coeliac disease (CD) is a disorder that may depend on genetic, immunological, and environmental factors. Recent observational studies suggest that breast feeding may prevent the development of CD. AIM: To evaluate articles that compared effects of breast feeding on risk of CD. METHODS: Systematic review and meta-analysis of observational studies published between 1966 and June 2004 that examined the association between breast feeding and the development of CD. RESULTS: Six case-control studies met the inclusion criteria. With the exception of one small study, all the included studies found an association between increasing duration of breast feeding and decreased risk of developing CD. Meta-analysis showed that the risk of CD was significantly reduced in infants who were breast feeding at the time of gluten introduction (pooled odds ratio 0.48, 95% CI 0.40 to 0.59) compared with infants who were not breast feeding during this period. CONCLUSIONS: Breast feeding may offer protection against the development of CD. Breast feeding during the introduction of dietary gluten, and increasing duration of breast feeding were associated with reduced risk of developing CD. It is, however, not clear from the primary studies whether breast feeding delays the onset of symptoms or provides a permanent protection against the disease. Long term prospective cohort studies are required to investigate further the relation between breast feeding and CD.

Smoking and age-related macular degeneration: a review of association.

PURPOSE: Age-related macular degeneration (AMD) is the leading cause of severe and irreversible vision loss in the Western world. As there is no effective treatment for all types of AMD, identifying modifiable risk factors is of great importance. This review evaluates the epidemiological evidence associating smoking with AMD. METHODS: Systematic review of published epidemiological studies evaluated against established criteria for evidence of a causal relationship. RESULTS: In total, 17 studies (cross-sectional studies, prospective cohort studies, and case-control studies) were included in the review. A total of 13 studies found a statistically significant association between smoking and AMD with increased risk of AMD of two- to three-fold in current-smokers compared with never-smokers. Five studies found no association between smoking and AMD. There was also evidence of dose-response, a temporal relationship and reversibility of effect. CONCLUSION: The literature review confirmed a strong association between current smoking and AMD, which fulfilled established causality criteria. Cigarette smoking is likely to have toxic effects on the retina. In spite of the strength of this evidence, there appears to be a lack of awareness about the risks of developing eye disease from smoking among both healthcare professionals and the general public.

Social trends in singleton births and birth weight in Wirral residents, 1990-2001.

OBJECTIVE: To examine social trends in the number of singleton births and birth weight in an English health district between 1990 and 2001, using an area based deprivation index. DESIGN: Analysis of routinely collected hospital data. SETTING: Wirral Health District in north west England. PARTICIPANTS: All 48 452 live births to Wirral residents from 1990 to 2001. MAIN OUTCOME MEASURES: Birth numbers, birth weight, and standard deviation score for birth weights for singleton births. Townsend material deprivation scores derived from postcodes. RESULTS: The number of singleton births fell by 28% over the 12 years. The fall in the least deprived Townsend quartile (45%) was more than triple that in the most deprived quartile (gamma = 0.045; 95% confidence interval (CI) = 0.036 to 0.054; p < 0.001). Over the study period, the mean birth weight in the least deprived Townsend quartile was 141 g higher than in the most deprived quartile. There was a highly significant association between the standard deviation score for birth weight and Townsend quartile (tau-b = -0.062; 95% CI = -0.068 to -0.055; p < 0.001). Numbers of low birth weight babies in the least deprived quartile fell disproportionately compared with those from the most deprived quartile (gamma = 0.17; 95% CI = 0.09 to 0.25; p < 0.001). CONCLUSION: The reduction in birth rate in the Wirral was significantly less in the most deprived districts. This was accompanied by related differences in mean birth weight and the number of low birth weight babies, indicating increasing social inequality in birth trends. Previously described social inequity in birth weight and the number of low birth weight babies continues in the north west of England.