Kate Northstone

Dietary patterns in UK adolescents obtained from a dual-source FFQ and their associations with socio-economic position, nutrient intake and modes of eating

OBJECTIVEnTo derive dietary patterns using principal components analysis from separate FFQ completed by mothers and their teenagers and to assess associations with nutrient intakes and sociodemographic variables.nnnDESIGNnTwo distinct FFQ were completed by 13-year-olds and their mothers, with some overlap in the foods covered. A combined data set was obtained.nnnSETTINGnAvon Longitudinal Study of Parents and Children (ALSPAC), Bristol, UK.nnnSUBJECTSnTeenagers (n 5334) with adequate dietary data.nnnRESULTSnFour patterns were obtained using principal components analysis: a Traditional/health-conscious pattern, a Processed pattern, a Snacks/sugared drinks pattern and a Vegetarian pattern. The Traditional/health-conscious pattern was the most nutrient-rich, having high positive correlations with many nutrients. The Processed and Snacks/sugared drinks patterns showed little association with important nutrients but were positively associated with energy, fats and sugars. There were clear gender and sociodemographic differences across the patterns. Lower scores were seen on the Traditional/health conscious and Vegetarian patterns in males and in those with younger and less educated mothers. Higher scores were seen on the Traditional/health-conscious and Vegetarian patterns in girls and in those whose mothers had higher levels of education.nnnCONCLUSIONSnIt is important to establish healthy eating patterns by the teenage years. However, this is a time when it is difficult to accurately establish dietary intake from a single source, since teenagers consume increasing amounts of foods outside the home. Further dietary pattern studies should focus on teenagers and the source of dietary data collection merits consideration.

Free Sugars and Total Fat Are Important Characteristics of a Dietary Pattern Associated with Adiposity across Childhood and Adolescence

Background: The importance of dietary sugar compared with fat in the development of obesity is currently a topic of debate. Objective: We aimed to identify dietary patterns (DPs) characterized by high sugar content, high fat content, or both and their longitudinal associations with adiposity during childhood and adolescence. Methods: Participants were 6722 children from the ALSPAC (Avon Longitudinal Study of Parents and Children) who were born in 1991–1992. DPs were characterized by percentage of total energy intake (%E) from free sugars, %E from total fat, and dietary energy density (DED) and fiber density by using reduced rank regression at 7, 10, and 13 y of age. Total body fat mass was measured at 11, 13, and 15 y of age. Regression analyses were used to adjust for dietary misreporting, physical activity, and maternal social class. Results: Two major DPs were identified: higher z scores for DP1 were associated with greater DED, greater %E from free sugars and total fat, and lower fiber density; higher z scores for DP2 were associated with greater %E from free sugars but lower %E from total fat and DED. A 1-SD increase in z score for DP1 was associated with a mean increase in the fat mass index z score of 0.04 SD units (95% CI: 0.01, 0.07; P = 0.017) and greater odds of excess adiposity (OR: 1.12; 95% CI: 1.0, 1.25; P = 0.038). DP2 was not associated with adiposity. Conclusions: An energy-dense DP high in %E from total fat and free sugars is associated with greater adiposity in childhood and adolescence. This appears to confirm the role of both fat and sugar and provides a basis for food-based dietary guidelines to prevent obesity in children.

Macro- and micronutrient intakes in picky eaters: a cause for concern?

Background: Picky eating (PE) is characterized by an unwillingness to eat certain foods and by strong food preferences. PE may result in lower intakes of energy and nutrients, which may compromise health. Objectives: We quantified nutrient and food group intakes in children identified as picky eaters or nonpicky eaters and compared intakes between groups and with United Kingdom reference nutrient intakes. Design: PE was identified in an observational cohort (Avon Longitudinal Study of Parents and Children) from questionnaires administered when children were aged 2, 3, 4.5, and 5.5 y. Dietary intake was assessed at 3.5 and 7.5 y with a 3-d food record. The dietary assessment at 3.5 y compared picky eaters with nonpicky eaters identified at age 3 y, and the assessment at 7.5 y compared longitudinally defined PE groups. Results: Picky eaters aged 3 y had lower mean carotene, iron, and zinc intakes than nonpicky eaters. There were similar differences between the longitudinally defined PE groups. Iron and zinc intakes were most likely to be below recommended amounts, with free sugar intake much higher than recommended. There were no significant differences in energy intakes between the groups, and intakes were adequate relative to estimated average requirements. Nutrient differences were explained by lower intakes of meat, fish, vegetables, and fruits in picky eaters than in nonpicky eaters. There were higher intakes of sugary foods and drinks in older picky eaters. Conclusions: PE did not result in compromised macronutrient intakes, although intakes of zinc and iron were more likely to be below recommendations for picky eaters than for nonpicky eaters. Emphasis should be placed on allaying parental concerns about picky eaters being prone to inadequate nutrient intakes and on encouraging all parents to extend their child’s diet to include more nutrient-rich items, especially fruits and vegetables, and less nutrient-poor sugary foods.

Does milk intake promote prostate cancer initiation or progression via effects on insulin-like growth factors (IGFs)? A systematic review and meta-analysis

PurposeTo establish whether the association between milk intake and prostate cancer operates via the insulin-like growth factor (IGF) pathway (including IGF-I, IGF-II, IGFBP-1, IGFBP-2, and IGFBP-3).MethodsSystematic review, collating data from all relevant studies examining associations of milk with IGF, and those examining associations of IGF with prostate cancer risk and progression. Data were extracted from experimental and observational studies conducted in either humans or animals, and analyzed using meta-analysis where possible, with summary data presented otherwise.ResultsOne hundred and seventy-two studies metxa0the inclusion criteria: 31 examining the milk–IGF relationship; 132 examining the IGF–prostate cancer relationship in humans; and 10 animal studies examining the IGF–prostate cancer relationship. There was moderate evidence that circulating IGF-I and IGFBP-3 increase with milk (and dairy protein) intake (an estimated standardized effect size of 0.10 SD increase in IGF-I and 0.05 SD in IGFBP-3 per 1 SD increase in milk intake). There was moderate evidence that prostate cancer risk increased with IGF-I (Random effects meta-analysis OR per SD increase in IGF-I 1.09; 95% CI 1.03, 1.16; nu2009=u200951 studies) and decreased with IGFBP-3 (OR 0.90; 0.83, 0.98; nu2009=u200939 studies), but not with other growth factors. The IGFBP-3 -202A/C single nucleotide polymorphism was positively associated with prostate cancer (pooled OR for A/C vs. AAu2009=u20091.22; 95% CI 0.84, 1.79; OR for C/C vs. AAu2009=u20091.51; 1.03, 2.21, nu2009=u20098 studies). No strong associations were observed for IGF-II, IGFBP-1 or IGFBP-2 with either milk intake or prostate cancer risk. There was little consistency within the data extracted from the small number of animal studies. There was additional evidence to suggest that the suppression of IGF-II can reduce tumor size, and contradictory evidence with regards to the effect of IGFBP-3 suppression on tumor progression.ConclusionIGF-I is a potential mechanism underlying the observed associations between milk intake and prostate cancer risk.

Use of a primary care online consultation system, by whom, when and why: evaluation of a pilot observational study in 36 general practices in South West England

Objectives Evaluation of a pilot study of an online consultation system in primary care. We describe who used the system, when and why, and the National Health Service costs associated with its use. Design 15-month observational study. Setting Primary care practices in South West England. Results 36 General practices covering 396u2009828 patients took part in the pilot. The online consultation website was viewed 35u2009981 times over the pilot period (mean 9.11 visits per 1000 patients per month). 7472 patients went on to complete an ‘e-consultation’ (mean 2.00 online consultations per 1000 patients per month). E-consultations were mainly performed on weekdays and during normal working hours. Patient records (n=485) were abstracted for eight practices and showed that women were more likely to use e-consultations than men (64.7% vs 35.3%) and users had a median age of 39 years (IQR 30–50). The most common reason for an e-consultation was an administrative request (eg, test results, letters and repeat prescriptions (22.5%)) followed by infections/immunological issues (14.4%). The majority of patients (65.2%) received a response within 2u2009days. The most common outcome was a face-to-face (38%) or telephone consultation (32%). The former were more often needed for patients consulting about new conditions (OR 1.56, 95%u2009CI 1.05 to 2.27, p=0.049). The average cost of a practice’s response to an e-consultation was £36.28, primarily triage time and resulting face-to-face/telephone consultations needed. Conclusions Use of e-consultations is very low, particularly at weekends. Unless this can be improved, any impact on staff workload and patient waiting times is likely to be negligible. It is possible that use of e-consultations increases primary care workload and costs. Online consultation systems could be developed to improve efficiency both for staff and patients. These findings have implications for software developers as well as primary care services and policy-makers who are considering investing in online consultation systems.

Dietary patterns and depressive symptoms in a UK cohort of men and women: a longitudinal study

Objective There is evidence to suggest that individual components of dietary intake are associated with depressive symptoms. Studying the whole diet, through dietary patterns, has become popular as a way of overcoming intercorrelations between individual dietary components; however, there are conflicting results regarding associations between dietary patterns and depressive symptoms. We examined the associations between dietary patterns extracted using principal component analysis and depressive symptoms, taking account of potential temporal relationships. Design Depressive symptoms in parents were assessed using the Edinburgh Postnatal Depression Scale (EPDS) when the study child was 3 and 5 years of age. Scores >12 were considered indicative of the presence of clinical depressive symptoms. Diet was assessed via FFQ when the study child was 4 years of age. Setting Longitudinal population-based birth cohort. Subjects Mothers and fathers taking part in the Avon Longitudinal Study of Parents and Children when their study child was 3–5 years old. Results Unadjusted results suggested that increased scores on the ‘processed’ and ‘vegetarian’ patterns in women and the ‘semi-vegetarian’ pattern in men were associated with having EPDS scores ≥13. However, after adjustment for confounders all results were attenuated. This was the case for all those with available data and when considering a sub-sample who were ‘disease free’ at baseline. Conclusions We found no association between dietary patterns and depressive symptoms after taking account of potential confounding factors and the potential temporal relationship between them. This suggests that previous studies reporting positive associations may have suffered from reverse causality and/or residual confounding.

Vegetarian diets and depressive symptoms among men

BACKGROUNDnVegetarian diets are associate with cardiovascular and other health benefits, but little is known about mental health benefits or risks.nnnAIMSnTo determine whether self-identification of vegetarian dietary habits is associated with significant depressive symptoms in men.nnnMETHODnSelf-report data from 9668 adult male partners of pregnant women in the Avon Longitudinal Study of Parents and Children (ALSPAC) included identification as vegetarian or vegan, dietary frequency data and the Edinburgh Post Natal Depression Scale (EPDS). Continuous and binary outcomes were assessed using multiple linear and logistic regression taking account of potential confounding variables including: age, marital status, employment status, housing tenure, number of children in the household, religion, family history of depression previous childhood psychiatric contact, cigarette and alcohol consumption.nnnRESULTSnVegetarians [n = 350 (3.6% of sample)], had higher depression scores on average than non-vegetarians (mean difference 0.96 points [95%CI + 0.53, + 1.40]) and a greater risk for EPDS scores above 10 (adjusted OR = 1.67 [95% CI: 1.14,2.44]) than non-vegetarians after adjustment for potential confounding factors.nnnCONCLUSIONSnVegetarian men have more depressive symptoms after adjustment for socio-demographic factors. Nutritional deficiencies (e.g. in cobalamin or iron) are a possible explanation for these findings, however reverse causation cannot be ruled out.

Use of an electronic consultation system in primary care: a qualitative interview study

Background The level of demand on primary care continues to increase. Electronic or e-consultations enable patients to consult their GP online and have been promoted as having potential to improve access and efficiency. Aim To evaluate whether an e-consultation system improves the ability of practice staff to manage workload and access. Design and setting A qualitative interview study in general practices in the West of England that piloted an e-consultation system for 15 months during 2015 and 2016. Method Practices were purposefully sampled by location and level of e-consultation use. Clinical, administrative, and management staff were recruited at each practice. Interviews were transcribed and analysed thematically. Results Twenty-three interviews were carried out across six general practices. Routine e-consultations offered benefits for the practice because they could be completed without direct contact between GP and patient. However, most e-consultations resulted in GPs needing to follow up with a telephone or face-to-face appointment because the e-consultation did not contain sufficient information to inform clinical decision making. This was perceived as adding to the workload and providing some patients with an alternative route into the appointment system. Although this was seen as offering some patient benefit, there appeared to be fewer benefits for the practices. Conclusion The experiences of the practices in this study demonstrate that the technology, in its current form, fell short of providing an effective platform for clinicians to consult with patients and did not justify their financial investment in the system. The study also highlights the challenges of remote consultations, which lack the facility for real time interactions.

Maturation in serum thyroid function parameters over childhood and puberty: results of a longitudinal study

Context: Serum thyroid hormone levels differ between children and adults, but have not been studied longitudinally through childhood. Objective: To assess changes in thyroid-stimulating hormone (TSH) and thyroid hormone levels over childhood and their interrelationships. Design: Cohort study. Setting: The Avon Longitudinal Study of Parents and Children, a population-based birth cohort. Participants: A total of 4442 children who had thyroid function measured at age 7, and 1263 children who had thyroid function measured at age 15. Eight hundred eighty-four children had measurements at both ages. Main Outcome Measures: Reference ranges for TSH, free tri-iodothyronine (FT3), free thyroxine (FT4), their longitudinal stability, and interrelationships. Results: Children at age 7 years had a higher FT3 [6.17 pmol/L, standard deviation (SD) 0.62] than children at age 15 (5.83 pmol/L, SD 0.74); P < 0.0001 with 23.2% of children at age 7 having FT3 above the adult reference range. Higher FT3 levels at age 7 in boys (P = 0.0001) and girls (P = 0.04) were associated with attainment of a more advanced pubertal stage at age 13. TSH was positively associated with FT3 at age 7 and age 15 even after adjusting for confounders. In contrast, TSH was negatively associated with FT4. Conclusions: There are substantial changes in TSH and thyroid hormone levels over childhood, in particular for FT3, which appear to relate to pubertal readiness. Our data provide increased insight into the evolution of the pituitary–thyroid axis over childhood and may have implications for determining optimal ranges for thyroid hormone replacement in children.

Prenatal exposure to polychlorinated biphenyls and fetal growth in British girls

Polychlorinated biphenyls (PCBs) are synthetic chemicals that bioaccumulate in the food chain. PCBs were used primarily for industrial applications due to their insulating and fire retardant properties, but were banned in the 1970s in the United States and in the 1980s in the United Kingdom, as adverse health effects following exposure were identified. Previous studies of populations with high PCB exposure have reported inverse associations with birth weight and gestational length. Birth weight is a powerful predictor of infant survival, and low birth weight can predispose infants to chronic conditions in adult life such as diabetes and cardiovascular diseases. Using data from the Avon Longitudinal Study of Parents and Children, we investigated the association between prenatal exposure to PCBs and fetal growth in a sample of 448 mother-daughter dyads. Concentrations of three common PCB analytes, PCB-118, PCB-153 and PCB-187, were measured in maternal serum collected during pregnancy, and fetal growth was measured by birth weight and birth length. Multivariable linear regression was used to examine the associations between PCB analytes and measures of fetal growth, after adjusting for parity, maternal age, pre-pregnancy BMI, educational status, tobacco use and gestational age of infant at sample collection. Birth length, ponderal index and gestational age were not associated with any of the PCB analytes. Mothers educational status modified associations for PCB analytes with birthweight. We observed significant inverse associations with birth weight only among daughters of mothers with less education. Daughters birth weight was -138.4u202fg lower (95% CI: -218.0, -58.9) for each 10u202fng/g lipid increase in maternal serum PCB-118. Similarly, every 10u202fng/g lipid increase in maternal serum PCB-153 was associated with a -41.9u202fg (95% CI: -71.6, -12.2) lower birth weight. Every 10u202fng/g lipids increase in maternal serum PCB-187, was associated with a -170.4u202fg (95% CI: -306.1, -34.7) lower birth weight, among girls with mothers in the lowest education group. Our findings suggest that prenatal exposure to PCBs is inversely associated with daughters birth weight and that mothers education, which is a possible marker for socioeconomic status, significantly modified the association between maternal PCB concentrations and birth weight in female newborns.