Rajalakshmi Lakshman

Early Age at Menarche Associated with Cardiovascular Disease and Mortality

CONTEXT The relationship between age at menarche and cardiovascular disease remains unclear. Two recent studies found an inverse association between age at menarche and all-cause mortality. OBJECTIVE The aim of this study was to examine the relationship between age at menarche and cardiovascular disease risk factors, events, and mortality. DESIGN, SETTING, AND PARTICIPANTS A population-based prospective study involving 15,807 women, aged 40-79 yr in 1993-1997 and followed up to March 2007 for cardiovascular disease events (median follow-up 10.6 yr) and February 2008 for mortality (median follow-up 12.0 yr) was used. MAIN OUTCOME MEASURES Odds ratios for cardiovascular disease risk factors and hazard ratios for incident cardiovascular disease and mortality were calculated. RESULTS There were 3888 incident cardiovascular disease events (1323 coronary heart disease, 602 stroke, and 1963 other) and 1903 deaths (640 cardiovascular disease, 782 cancer, and 481 other) during follow-up. Compared with other women, those who had early menarche (<12 yr) had higher risks of hypertension [1.13 (1.02-1.24)], incident cardiovascular disease [1.17 (1.07-1.27)], incident coronary heart disease [1.23 (1.06-1.43)], all-cause mortality [1.22 (1.07-1.39)], cardiovascular disease mortality [1.28 (1.02-1.62)], and cancer mortality [1.25 (1.03-1.51)], adjusted for age, physical activity, smoking, alcohol, educational level, occupational social class, oral contraceptive use, hormone replacement therapy, parity, body mass index, and waist circumference. CONCLUSIONS Early age at menarche (before age 12 yr) was associated with increased risk of cardiovascular disease events, cardiovascular disease mortality, and overall mortality in women, and this association appeared to be only partly mediated by increased adiposity.

Determinants of Early Weaning and Use of Unmodified Cow's Milk in Infants: A Systematic Review

Introduction of complementary foods (weaning) before 4 to 6 months of age and unmodified cows milk before age 12 months are associated with several health risks. To develop effective interventions to discourage these practices, evidence of their determinants is needed. This systematic review identified documents from seven electronic databases (database inception 2008) and reference lists, and by contacting authors. Seventy-eight studies in developed countries, published between 1976 and 2008, quantifying the association between either feeding practice and its potential determinants were included. Study quality was systematically assessed in terms of representativeness, sample size, method of outcome ascertainment, and approach to statistical analysis. The distribution of evidence for each determinant was visualized in a harvest plot showing the strength and direction of associations found and the quality of relevant studies. The strength of evidence for each determinant was summarized as strong, moderate, limited, or inconclusive, using an algorithm based on the consistency of the results of studies of the highest available quality. Strong evidence denoted that the determinant was examined in three or more high-quality studies and >/=75% of results were consistent. Strong evidence was found for six determinants of early weaning (ie, young maternal age, low maternal education, low socioeconomic status, absence or short duration of breastfeeding, maternal smoking, and lack of information or advice from health care providers) and for two determinants of early introduction of unmodified cows milk (ie, low maternal education and low socioeconomic status). Of these determinants, improving advice given by health care providers appears the most tractable area for intervention in the short term.

Mothers' experiences of bottle feeding: a systematic review of qualitative and quantitative studies

Objective: Most babies receive at least some formula milk. Variations in formula-feeding practices can have both short- and long-term health consequences. The literature on parents’ experiences of bottle-feeding was systematically reviewed to understand how formula-feeding decisions are made. Methods: Relevant English-language papers, identified by searching 12 electronic databases, reference lists and related articles and by contacting first authors of included papers, were systematically searched for and appraised. The included studies were analysed and synthesised using a combination of narrative and thematic approaches. Consensus on the final inclusion, interpretation and synthesis of studies was reached across the research team. Results: Six qualitative studies and 17 quantitative studies (involving 13 263 participants) were included. Despite wide differences in study design, context, focus and quality, several consistent themes emerged. Mothers who bottle-fed their babies experienced negative emotions such as guilt, anger, worry, uncertainty and a sense of failure. Mothers reported receiving little information on bottle-feeding and did not feel empowered to make decisions. Mistakes in preparation of bottle-feeds were common. No studies examined how mothers made decisions about the frequency or quantity of bottle-feeds. Conclusions: Inadequate information and support for mothers who decide to bottle-feed may put the health of their babies at risk. While it is important to promote breastfeeding, it is also necessary to ensure that the needs of bottle-feeding mothers are met.

Implications of adopting the WHO 2006 Child Growth Standard in the UK: two prospective cohort studies

Background: The WHO 2006 Child Growth Standard is based on data from international optimally nourished breastfed infants from birth to age 5 years. Objective: To assess the potential effect of its use on weight and growth monitoring of UK children. Participants: Full-term members of two population-based UK birth cohorts: the Children in Focus sub-cohort of the Avon Longitudinal Study of Parents and Children (ALSPAC) (n = 1335) and the Gateshead Millennium Baby Study (GMS; n = 923). Design: Growth data from birth to 5 years were converted into z-scores relative to the WHO 2006 standard. Results: Compared with the WHO standard, both UK cohorts had higher birth weights (mean z-scores: GMS, 0.17; ALSPAC, 0.34) and ALSPAC had higher birth lengths. After birth, length showed a good fit at all ages. By 2–4 months, both cohorts were similar in weight to the WHO median (mean WHO weight z-score at 4 months: GMS, 0.01; ALSPAC, −0.07), but thereafter the UK cohorts were heavier (mean WHO weight z-score at 12 months: GMS, 0.57; ALSPAC, 0.65). At age 12 months, the risk of being classified as underweight (weight <2nd centile) was considerably lower according to the WHO standard than by the UK 1990 Growth Reference (RR = 0.15, 95% CI = 0.07 to 0.32), and the risk of being classified as obese at 4–5 years (body mass index >98th centile) was slightly increased (RR = 1.35, 95% CI = 1.02 to 1.78). Conclusions: Adoption of the WHO 2006 Growth Charts would set a markedly lower standard of weight gain beyond the age of 4 months for UK infants and could support efforts to avoid future childhood obesity. However, the WHO standard is not representative of size at birth in the UK.

Association between area-level socioeconomic deprivation and a cluster of behavioural risk factors: cross-sectional, population-based study.

BACKGROUND The Commission on Social Determinants of Health has urged governments across the world to promote health equity by reducing the gap between the most and least deprived individuals in society. Some of this gap can be bridged by promoting healthy lifestyles through targeted Public Health policy and interventions. METHODS Cross-sectional analyses of data on behavioural risk factors, individual socioeconomic factors and neighbourhood deprivation score collected from 26 290 adults aged over 16 years who participated in the 2008 East of England Lifestyle Survey. RESULTS After adjustment for individual socioeconomic factors, across quintiles of increasing neighbourhood deprivation, participants were more likely to smoke and less likely to consume five portions of fruit and vegetables on five or more days of the week (least deprived versus most deprived quintile: odds ratios for not smoking 0.45 (0.41-0.50); and fruit and vegetable consumption 0.70 (0.64-0.76), P-trend <0.0001). Greater neighbourhood deprivation and lower occupational social class were independently associated with a lower summary healthy lifestyle score (both P-trend <0.0001). CONCLUSIONS Public health interventions aimed at reducing health inequalities by targeting behavioural risk factors may focus in particular on reducing smoking and increasing fruit and vegetable consumption in more deprived communities.

Factors influencing obesogenic dietary intake in young children (0–6 years): systematic review of qualitative evidence

Background Obesogenic dietary intake is prevalent in young children and is associated with obesity and other adverse health outcomes in childhood and later in life. Objective To describe the barriers to and facilitators of obesogenic dietary intake in early childhood, in order to inform interventions and public health policies to prevent obesity. Design Systematic review of qualitative literature on factors influencing obesogenic diets in children aged 0–6 years. Data sources MEDLINE, EMBASE, CINAHL, PsycINFO, Web of Knowledge, British Nursing Index, ASSIA and Sociological Abstracts. Review methods Qualitative studies meeting the inclusion criteria were synthesised. Data were analysed by creating a thematic framework, underpinned by the socioecological model, which included familiarisation of data across the studies, indexing, charting, mapping and interpretation. Results 20 studies from the USA (10), Europe (6) and Australia (4) included the views of 1067 participants (901 parents/caregivers, 37 children, 87 teachers, 15 dieticians and 27 nursery staff). Study designs included focus groups (n=16), individual interviews (n=6) and ethnography (n=1) with some studies using more than one design. Despite wide differences in the study context and focus, several consistent themes emerged. Parental factors increasing young childrens obesogenic diets were: negative parent/family/peer modelling, lack of knowledge, time constraints, using food as reward, affordability and concerns about childs health. Child preferences also increased intake. Environmental factors increasing intake include: availability, advertising, societal, cultural and preschool/childcare influences. Conclusions Future intervention strategies should aim to promote modelling of positive behaviours, create home and preschool environments that promote healthy diets, and simultaneously target factors at the family and preschool/childcare levels. Trial registration number This review is one of a series of systematic reviews on the determinants of obesogenic behaviours in young children, registered with the International Prospective Register for Systematic Reviews (PROSPERO), CRD42012002881.

Higher maternal education is associated with favourable growth of young children in different countries

Background Childhood growth affects long-term health and could contribute to health inequalities that persist throughout life. Methods We compared growth data of 4-year-old to 6-year-old children born 1997–2002 in UK (n=15 168), Sweden (n=6749) and rural China (n=10 327). SD scores (SDS) were calculated against the WHO Growth Standard. Obesity and overweight were defined by the International Obesity Taskforce cut-offs, and stunting, underweight and thinness by height, weight or body mass index (BMI)<−2 SDS. Associations with maternal education were standardised by calculating the Slope Index of Inequality (SII). Results Mean SDS height, weight and BMI in the UK (−0.01, 0.42, 0.62, respectively) and Sweden (0.45, 0.59, 0.45) were higher than in China (−0.98, −0.82, −0.29). Higher maternal education was consistently associated with taller offspring height SDS (SII: UK 0.25; Sweden 0.17; China 1.06). Underweight and stunting were less common in the UK (prevalence: 0.6% and 2.2%, respectively) and Sweden (0.3% and 0.6%) than in China (9.5% and 16.4%), where these outcomes were inversely associated with maternal education (SII: −25.8% and −12.7%). Obesity prevalence in the UK, Sweden and China was 4.8%, 3.7% and 0.4%, respectively. Maternal education was inversely associated with offspring obesity in the UK (SII: −3.3%) and Sweden (−2.8%), but not in China (+0.3%). Conclusions Higher maternal education was associated with more favourable growth in young children: lower obesity and overweight in the UK and Sweden, and lower stunting and underweight in rural China. Public health strategies to optimise growth in early childhood need to acknowledge socioeconomic factors, but possibly with a different emphasis in different settings.

Protocol for systematic reviews of determinants/correlates of obesity-related dietary and physical activity behaviors in young children (preschool 0 to 6 years): evidence mapping and syntheses

BackgroundThe aim of these reviews is to inform the design and content of interventions to reduce obesity in young children. The behaviors that are associated with obesity/overweight have been studied extensively; however, the factors associated with these behaviors in young children (0 to 6 years) have not been systematically reviewed. Over the past few years the focus of obesity prevention has shifted to preschool children because of the high prevalence of obesity at school entry and recognition that habits formed in early life could track into adulthood. In order to develop effective interventions and change behavior, it is important to understand the factors that are associated with those behaviors. For example, we need to understand whether it would be more important to target the family, childcare settings or the wider environment and identify the most effective way of changing these energy balance related behaviors.Methods/DesignQuantitative (intervention and observational) and qualitative literature on determinants/correlates of fruit and vegetable intake, sugar sweetened beverage and other unhealthy diet intake, and physical activity and sedentary behaviors in young children will be systematically identified, mapped and reviewed. A common search strategy (no language or period restrictions) will be used to identify papers from eight electronic databases and this will be supplemented by hand-searching. Next, studies in developed countries that examine the factors associated with these behaviors in children aged 0 to 6 years (at baseline) will be screened and mapped descriptively followed by in-depth data extraction, quality assessment and synthesis. Data from quantitative studies will be summarized using either forest plots or harvest plots and narrative synthesis, and qualitative studies using thematic analysis. Qualitative evidence will be integrated with the quantitative evidence, using a parallel synthesis approach, to provide a deeper understanding of effective strategies to influence these energy balance related behaviors.DiscussionIn addition to updating and mapping current research, these reviews will be the first to comprehensively synthesize and integrate both the quantitative and qualitative evidence pertaining to determinants/correlates/barriers/facilitators of obesity related behaviors in this young age group (0 to 6 years) with the aim of informing future interventions.Systematic review registrationInternational Prospective Register for Systematic Reviews (PROSPERO) Registration number: CRD42012002881

Barriers and facilitators to young children’s physical activity and sedentary behaviour: a systematic review and synthesis of qualitative literature

Positive activity behaviours (i.e. higher physical activity [PA]/lower sedentary behaviour [SB]) are beneficial from infancy, yet evidence suggests that young children (0‐ to 6‐year‐olds) are relatively inactive. To better understand the perceived influences on these behaviours and to aid intervention development, this paper systematically synthesizes the extensive qualitative literature regarding perceived barriers and facilitators to PA and SB in young children (0–6 years old). A search of eight electronic databases (July 2016) identified 43 papers for inclusion. Data extraction and evidence synthesis were conducted using thematic content analysis, underpinned by the socio‐ecological model (i.e. individual, interpersonal, community, organizational and policy levels). Parents, childcare providers and children perceived seven broad themes to be important for PA and SB, including the child; the home; out‐of‐home childcare; parent–childcare provider interactions; environmental factors; safety; and weather. Each theme mapped onto between one and five levels of the socio‐ecological model; barriers and facilitators at the interpersonal level (e.g. parents, care providers and family) were most frequently cited, reflecting the important (perceived) role adults/peers play in shaping young childrens behaviours. We provide an overarching framework to explain PA and SB in early childhood. We also highlight where gaps in the current literature exist (e.g. from male carers; in developing countries; and barriers and facilitators in the environmental and policy domains) and where future quantitative work may focus to provide novel insights about childrens activity behaviours (e.g. safety and weather).

Using the Medical Research Council framework for the development and evaluation of complex interventions in a theory-based infant feeding intervention to prevent childhood obesity: the baby milk intervention and trial.

Introduction. We describe our experience of using the Medical Research Council framework on complex interventions to guide the development and evaluation of an intervention to prevent obesity by modifying infant feeding behaviours. Methods. We reviewed the epidemiological evidence on early life risk factors for obesity and interventions to prevent obesity in this age group. The review suggested prevention of excess weight gain in bottle-fed babies and appropriate weaning as intervention targets; hence we undertook systematic reviews to further our understanding of these behaviours. We chose theory and behaviour change techniques that demonstrated evidence of effectiveness in altering dietary behaviours. We subsequently developed intervention materials and evaluation tools and conducted qualitative studies with mothers (intervention recipients) and healthcare professionals (intervention deliverers) to refine them. We developed a questionnaire to assess maternal attitudes and feeding practices to understand the mechanism of any intervention effects. Conclusions. In addition to informing development of our specific intervention and evaluation materials, use of the Medical Research Council framework has helped to build a generalisable evidence base for early life nutritional interventions. However, the process is resource intensive and prolonged, and this should be taken into account by public health research funders. This trial is registered with ISRTCN: 20814693 Baby Milk Trial.