Strengthening the Reporting of Observational Studies in Epidemiology - nutritional epidemiology (STROBE-nut): An extension of the STROBE statement.

Concerns have been raised about the quality of reporting in nutritional epidemiology. Research reporting guidelines such as the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement can improve quality of reporting in observational studies. Herein, we propose recommendations for reporting nutritional epidemiology and dietary assessment research by extending the STROBE statement into Strengthening the Reporting of Observational Studies in Epidemiology - Nutritional Epidemiology (STROBE-nut). Recommendations for the reporting of nutritional epidemiology and dietary assessment research were developed following a systematic and consultative process, co-ordinated by a multidisciplinary group of 21 experts. Consensus on reporting guidelines was reached through a three-round Delphi consultation process with 53 external experts. In total, 24 recommendations for nutritional epidemiology were added to the STROBE checklist. When used appropriately, reporting guidelines for nutritional epidemiology can contribute to improve reporting of observational studies with a focus on diet and health.

What happens to food choices when a gluten-free diet is required? A prospective longitudinal population-based study among Swedish adolescent with coeliac disease and their peers.

A dietary survey was performed during a large screening study in Sweden among 13-year-old adolescents. The aim was to study how the intake of food groups was affected by a screening-detected diagnosis of coeliac disease (CD) and its gluten-free (GF) treatment. Food intake was reported using a FFQ, and intake reported by the adolescents who were diagnosed with CD was compared with the intake of two same-aged referent groups: (i) adolescents diagnosed with CD prior to screening; and (ii) adolescents without CD. The food intake groups were measured at baseline before the screening-detected cases were aware of their CD, and 12-18 months later. The results showed that food intakes were affected by screen-detected CD and its dietary treatment. Many flour-based foods were reduced such as pizza, fish fingers and pastries. The results also indicated that bread intake was lower before the screened diagnosis compared with the other studied groups, but increased afterwards. Specially manufactured GF products (for example, pasta and bread) were frequently used in the screened CD group after changing to a GF diet. The present results suggest that changing to a GF diet reduces the intake of some popular foods, and the ingredients on the plate are altered, but this do not necessarily include a change of food groups. The availability of manufactured GF replacement products makes it possible for adolescents to keep many of their old food habits when diagnosed with CD in Sweden.

Nutrient intake in adolescent girls and boys diagnosed with coeliac disease at an early age is mostly comparable to their non-coeliac contemporaries.

BACKGROUND: Food habits, nutrient needs and intakes differ between males and females, although few nutritional studies on patients with coeliac disease (CD) have reported results stratified by gender. OBJECTIVES: To compare energy and nutrient intakes among 13-year olds diagnosed with CD in early childhood with those of a non-coeliac (NC) age- and gender-matched control group, and also with estimated average requirements (EAR). METHODS: A case-control study was conducted in Sweden 2006-2007 within the coeliac screening study ETICS (Exploring The Iceberg of Coeliacs in Sweden). Dietary intake was assessed among 37 adolescents (23 girls) diagnosed with CD at median age 1.7 years (CD group) and 805 (430 girls) NC controls (NC group) using a food-frequency questionnaire covering 4 weeks. Reported energy intake was validated by comparison with the calculated physical activity level (PAL). RESULTS: Regardless of CD status, most adolescents reported an intake above EAR for most nutrients. However, both groups had a low intake of vitamin C, with 13% in the CD-group and 25% in the NC-group below EAR, and 21% of boys in the CD-group below EAR for thiamine. The intake of fatty acids was unbalanced, with a high intake of saturated and a low intake of unsaturated fats. Girls and boys in the CD-group had an overall lower nutrient density in reported food intake compared to girls and boys in the NC-group. CONCLUSIONS: Nutrient intake of adolescent girls and boys with CD was mostly comparable to intakes of NC controls. Dietitians should take the opportunity to reinforce a generally healthy diet when providing information about the gluten-free diet.

Serum lipid and apolipoprotein levels in 4-year-old children are associated with parental levels and track over time.

BACKGROUND/OBJECTIVES: There are only a few studies linking dietary fat intake to serum lipid levels in young children. Our objective was to prospectively evaluate serum lipid levels from infancy to early childhood, and to explore their possible association with dietary, growth and parental factors. SUBJECTS/METHODS: Children (n=127) followed from early infancy were examined for serum lipid levels, anthropometry and dietary intake at 4 years of age. We also studied possible associations with parental anthropometric and blood biochemistry data collected from 122 mothers' and 118 fathers' when children were 4 years of age. RESULTS: Serum concentrations of total cholesterol (TC), high-density lipoprotein cholesterol (HDLC), low-density lipoprotein cholesterol (LDLC) and the apolipoprotein B/apolipoprotein A-1 ratio (apo B/apo A-1) showed significant tracking from infancy to 4 years. Furthermore, children's TC levels correlated with paternal TC level from 6 months to 4 years, but with maternal only at 4 years. In girls, both LDLC and HDLC correlated with parental LDLC and HDLC. In all children, intake of saturated fatty acids (SAFAs) was higher than recommended, and in 90% of the children polyunsaturated fatty acid (PUFA) intake was lower than recommended. CONCLUSIONS: Serum lipid levels values tracked from infancy to 4 years and were associated with parental values. Higher serum lipid levels at 4 years compared with 6-18 months of age may result from changes in the quality of dietary fat. We therefore suggest that intake of dietary fat in 4-year-old children should be more focused on quality. Furthermore, as there were strong associations between the child and parental serum lipid levels this supports the view that family-based rather than individual intervention is preferable.

BMI at 4 years of age is associated with previous and current protein intake and with paternal BMI.

OBJECTIVES: To evaluate possible associations between body mass index (BMI) at 4 years of age, current and previous dietary intakes and parental BMI. METHODS: A follow-up of dietary intake and anthropometry in 127 4-year-old children corresponding to 54% of children who completed an initial intervention study at 18 months of age. RESULTS: Fourteen percent of the girls and 13% of the boys were overweight (age-adjusted BMI> or =25) and 2% of the girls and 3% of the boys were obese (age-adjusted BMI> or =30). Thirty-four percent and 9% of the fathers and 19 and 7% of the mothers were overweight and obese, respectively. BMI at 6-18 months was a strong predictor of BMI at 4 years. Univariate regression analyses revealed that intake of protein in particular, and also of total energy and carbohydrates at 17/18 months and at 4 years, was positively associated with BMI at 4 years. Although BMI at 6-18 months was the strongest predictor of BMI at 4 years, in the final multivariate models of the child's BMI, protein intake at 17-18 months and at 4 years, energy intake at 4 years and the father's-but not the mother's-BMI were also independent contributing factors. CONCLUSIONS: Among these healthy children, BMI at 4 years of age tracked from 6 to 18 months of age and were associated with previous and current protein intake as well as parental BMI, particularly that of the father.

The everyday life of adolescent coeliacs: issues of importance for compliance with the gluten-free diet.

BACKGROUND: Noncompliance with the gluten-free diet is often reported among adolescents with coeliac disease. However, knowledge is limited regarding their own perspectives and experiences of managing the disease and the prescription of a gluten-free diet. The aim of this study was to explore how adolescents with coeliac disease perceive and manage their everyday lives in relation to a gluten-free diet. METHODS: In total, 47 adolescents with coeliac disease, divided into 10 focus groups, were interviewed. In the qualitative analysis, themes emerged to illustrate and explain the adolescents' own perspectives on life with a gluten-free diet. RESULTS: The probability of compliance with the gluten-free diet was comprised by insufficient knowledge of significant others, problems with the availability and sensory acceptance of gluten-free food, insufficient social support and their perceived dietary deviance. Three different approaches to the gluten-free diet emerged: compliers, occasional noncompliers, and noncompliers. Each approach, as a coping strategy, was rational in the sense that it represented the adolescents' differing views of everyday life with coeliac disease and a prescription of a gluten-free diet. CONCLUSIONS: dolescents with coeliac disease experience various dilemmas related to the gluten-free diet. The study demonstrated unmet needs and implies empowerment strategies for optimum clinical outcomes.

Dietary fat in infancy should be more focused on quality than on quantity.

OBJECTIVE: The primary aim was to assess, the association of the quantity and quality of dietary fat intake from 6 to 12 months of age and serum lipids at 12 months. SUBJECTS/METHODS: Three hundred healthy term Swedish infants were recruited in a longitudinal prospective study at the age of 6 months; 276 remained in the study at 12 months. Food records and anthropometric data were collected monthly from 6 to 12 months; serum lipids were analysed at 6 and 12 months. RESULTS: Swedish infants had a total fat intake within the Nordic recommendations, but intake of polyunsaturated fatty acids (PUFA) was low (5.6 percent of total energy (E%)) and intake of saturated fatty acids (SAFA) was high (15.1 E%). Higher PUFA intake was associated with lower total serum cholesterol (TC, B=-0.13, P=0.003), lower low-density-lipoprotein cholesterol (LDL-C, B=-0.12, P=0.004) and apolipoprotein B (B=-0.03) (P=0.034) in girls but not in boys. When data from the present study were compared to data from similar studies in Finland and Iceland, it appears that the quality of the dietary fat has greater impact on serum lipid levels than the quantity of fat in the diet. CONCLUSIONS: Higher PUFA and lower SAFA intakes may reduce TC and LDL-C early in life, particularly in girls. Further, with respect to lowering serum lipid concentrations in early childhood it seems appropriate to set focus on fat quality rather than the quantity. SPONSORSHIPS: Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (Formas), Swedish Research Council, Medicine, Stiftelsen Oskar Foundation, Sven Jerring Foundation, Samariten Foundation, Stiftelsen Goljes minne and Semper AB.

Introduction of solids and formula to breastfed infants: a longitudinal prospective study in Uppsala, Sweden.

UNLABELLED: The introduction of solids and formula was studied among 506 breastfed infants in Uppsala, Sweden, based on daily recordings during the first year. The mothers had previously breastfed at least 1 infant for at least 4 mo. Thirty-four per cent of the infants were introduced to solids before the age of 4 mo (4-6 mo is recommended in Sweden). Accustoming the infants to solids was a lengthy process. Life-table analyses showed a median duration of 28 d from the first introduction of solids to consumption of >10 ml daily, and 46 d before the infants ate > or = 100 ml of solids in 1 d for the first time. These durations were longer the younger the infant was at the introduction of solids. Thirty-two per cent of infants given formula consumed > or = 100 ml the first time it was given, and 49% did so within I wk, regardless of infant age. CONCLUSION: Parents and healthcare personnel need to be aware that accustoming breastfed infants to solid food is a lengthy process, and that there is a strong age effect on this duration. It is also important to consider what consequences the (usually) more abrupt introduction of formula might have on breastfeeding.

Solids and formula: association with pattern and duration of breastfeeding.

OBJECTIVES: To study changes in pattern and duration of breastfeeding associated with the introduction of solids and formula. STUDY DESIGN: Descriptive longitudinal, prospective study. SETTING: The participants were recruited from the maternity ward in the University Hospital in Uppsala, Sweden, between May 1989 and December 1992. A total of 15 189 infants were born during the period, 1 177 mother-infant pairs were found eligible for participation; 57% declined because of the perceived high workload. Study Population. Five hundred six mother-infant pairs. METHODS: Daily recordings by the mothers on infant feeding, from the first week after delivery to the second menstruation postpartum or a new pregnancy; fortnightly home visits with structured interviews by a research assistant. RESULTS: Introduction of solids was associated with no or minor changes in breastfeeding frequency and suckling duration. Breastfeeding frequency remained constant the first month after the introduction and then declined slowly, while daily suckling duration started to decline slowly when solids were introduced. Breastfeeding duration was not associated with infants' age at introduction of solids. In infants given formula, as soon as regular formula feeds started, the breastfeeding frequency and suckling duration declined swiftly. The younger an infant was at the start of regular formula feeds, the shorter the breastfeeding duration. CONCLUSIONS: Health care personnel and parents need to be aware that introduction of solids and introduction of formula can have very different consequences for breastfeeding. If the aim is to introduce other foods to breastfed infants under the protection of breast milk, it is important to realize that formula is also another food and needs to be treated as such.

How exclusive is exclusive breastfeeding? A comparison of data since birth with current status data.

BACKGROUND: There is no accepted and widely used indicator for exclusive breastfeeding since birth. Indeed, the difference between 'current status' data on exclusive breastfeeding and data on 'exclusive breastfeeding since birth' is rarely recognized. We used data from a longitudinal study to examine this issue. METHODS: A descriptive longitudinal, prospective study design was used in which 506 mother-infant pairs were included. The mothers completed daily recordings on infant feeding during the first nine months after birth. A research assistant conducted fortnightly home visits with structured interviews. The resulting data on breastfeeding patterns are presented in two different ways: analysis of 'current status' data based on a single 24-hour recording of infant feeding at 2, 4 and 6 months of age, and analysis of data 'since birth', i.e. data on infant feeding for every day, starting from birth until the ages of 2, 4 and 6 months. RESULTS: A wide discrepancy between the results obtained from the two analyses was found. The difference in the exclusive breastfeeding rate was over 40 percentage points at both 2 and 4 months of age (92% versus 51% at 2 months and 73% versus 30% at 4 months) and 9 percentage points at 6 months (11% versus 1.8%). CONCLUSIONS: Current status indicators based on a 24-hour period may be inadequate and even misleading for many purposes. We propose that in many studies an indicator called 'exclusive breastfeeding since birth' could be added.

Breastfeeding patterns in relation to thumb sucking and pacifier use.

OBJECTIVES: To analyze the influence of thumb sucking and pacifier use on breastfeeding patterns in exclusively breastfed infants, on the duration of exclusive breastfeeding, and on the total breastfeeding duration. STUDY DESIGN: Descriptive, longitudinal, prospective study. SETTING: The subjects were recruited from a population of 15 189 infants born in the maternity ward at the University Hospital, Uppsala, Sweden between May 1989 and December 1992. STUDY POPULATION: 506 mother-infant pairs. METHODS: Daily recordings by the mothers on infant feeding from the first week after delivery through the duration of the study. Fortnightly home visits with structured interviews by a research assistant. RESULTS: Pacifier use was associated with fewer feeds and shorter suckling duration per 24 hours, shorter duration of exclusive breastfeeding, and shorter total breastfeeding duration compared with no pacifier use. These associations were not found for thumb sucking. The possible negative effects of pacifiers on breastfeeding seemed to be related to the frequency of their use. Maternal age and education only slightly modified the association between pacifier use and breastfeeding duration. CONCLUSIONS: More frequent use of a pacifier was associated with shorter breastfeeding duration, even among a group of mothers who were highly motivated to breastfeed. breastfeeding duration, breastfeeding pattern, exclusive breastfeeding, pacifier use, thumb sucking.

Breastfeeding patterns in exclusively breastfed infants: a longitudinal prospective study in Uppsala, Sweden.

Exclusive breastfeeding was studied among 506 infants in Uppsala, Sweden, based on daily recordings during the first 6 mo. The mothers had previously breastfed at least one infant for at least 4 mo. Most of the mothers considered that they breastfed on demand. Wide variations in breastfeeding frequency and suckling duration were found both between different infants and in the individual infant over time. At 2 wk, the mean frequency of daytime feeds (based on one 13-d record) between different infants ranged from 2.9 to 10.8 and night-time feeds from 1.0 to 5.1. The daytime suckling duration (based on one 24-h record) ranged from 20 min to 4h 35 min and night-time duration from 0 to 2h 8 min. At any given age, a maximum of only 2% of the infants were not breastfed during the night. At 4 mo, 95% of the infants were breastfeeding and 40% were exclusively breastfed at this age. Longer breastfeeding duration and longer duration of exclusive breastfeeding were both associated with higher frequency of breastfeeds, longer breastfeeding of the previous child and higher education. No gender differences were found. Maternal smoking was associated with shorter duration of exclusive breastfeeding, and pacifier use was associated with shorter duration of both exclusive breastfeeding and total breastfeeding. This study confirms that every mother-infant pair needs to be understood as a unique dyad throughout lactation. These data demonstrate a wide range of patterns among women who are exclusively breastfeeding and indicate that it would be inappropriate to put pressure on individual families to adopt preconceived patterns of infant feeding.